Head and Neck Flashcards

Question

What is the 2/3 rule for salivary gland tumors?

Answer 1

2/3 of all lesions in the salivary glands would be benign. 2/3 of these lesions would be a pleomorphic adenoma. 2/3 of these will be located in the parotid gland.

Answer 2

Parotid Submandibular Sublingual

Answer 3

700 - 1000 minor salivary glands

Answer 4

Parotid - If mass is big enough to extend beyond the facial nerve, do a total parotidectomy. Otherwise, do a superficial parotidectomy. - A pleomorphic adenoma has a pseudocapsule. There are finger-like projections extending beyond the visible capsule. Hence if there is no significant margin during resection, there is a very high recurrence rate. Submandibular gland - Once a tumor grows, remove the entire submandibular gland.

Answer 5

No need to do biopsy. Basis for diagnosis would be clinical-- look for: - fixation/mobility - consistency (hard) - facial nerve involvement - nodal involvement - skin involvement - extension to the oral cavity. Determine two things: size and grade. Only 3 types of malignancies have a low-grade and a high-grade component: 1) Mucoepidermoid carcinoma 2) Acinic cell carcinoma 3) Adenocarcinoma T1: ≤2cm T2: >2cm, but ≤4cm T3: >4cm T4: Extension to adjacent structures For T1-T2 (low-grade): Superficial parotidectomy or submandibular gland excision T3-T4 (low-grade), any T, high grade lesions with no clinically palpable neck nodes (N0): Total Parotidectomy + SOHND + Postoperative RT to the wall *Remember that submandibular gland removal is part of level I dissection.

Answer 6

You could opt to do frozen section.

Answer 7

Submandibular Gland Excision - injury to the nerve causing loss of taste (chorda tympanii of facial nerve CN VII) and sensation (lingual nerve of trigeminal CN V3) - injury to the marginal mandibular branch of the facial nerve. Parotidectomy - Frey' syndrome: aka auriculotemporal syndrome, characterized by gustatory sweating and flushing. Diagnosed by a minor starch-iodine test. The starch-iodine test consists of painting the patient’s postsurgical affected region with iodine, in which the starch turns blue/brown in the presence of iodine and sweat. Treated with topical antiperspirants and botulinum toxin A. - Fistula formation: Treatment is conservative with application of pressure dressings. Problem is in failure to ligate Stensen's duct.

Answer 8

Smoking (chronic irritation) Alcohol intake Ill-fitting dentures Premalignant lesion: Leukoplakia

Answer 9

T1-T2: Wide excision T3-T4: Wide excision + SOHND (if cN0) + Postop radiotherapy *Same as salivary gland lesions.

Answer 10

Punch biopsy. But your major concern is the extent of the primary cancer. By size and proximity, check for mandibular involvement using a panorex view. If only periosteum is involved, do a marginal mandibulectomy (1cm inferior portion of the mandible is left in place, 1cm because any smaller and the bone will weaken and fracture). What is the principle behind this? The periosteum is a very good barrier against tumor invasion. The malignant cells will slide over it and enter the bone through the natural openings for tooth growth. If there is gross bony involvement, do segmental mandibulectomy.

Answer 11

The floor of the mouth and tongue are both considered to be midline structures. Therefore, lymphatic spread is to both sides of the neck. T3-T4 lesions with N0 neck: Bilateral SOHND One side N0, other side N+: Do SOHND in the N0 side, and a full neck dissection in the N+ side. Both N+: Do a full neck dissection on both sides. Never do bilateral Radical Neck Dissection. Removal of both IJVs will cause cerebral edema. Only ONE IJV can be removed. The tongue is notorious for having skip node metastases. They may have enlarged nodes in level V, even without palpable nodes in level I-IV. Hence tongue malignancies warrant a bilateral full neck dissection.

Answer 12

Soft tissue defects can be restored with myocutaneous flaps. Bony defects can be restored with titanium plates, bone grafts, and wires. Bone grafts can only be used in defects <6cm. It can not be used for larger defects because the bone will resorb.

Answer 13

As in the pharynx, the newest treatment modality involves chemotherapy and radiotherapy for all stages, because of the emphasis on organ preservation. However, it is yet to be adapted in our local setting. Remember that the larynx is divided into 3 regions: supraglottic, glottic and subglottic, with SUBGLOTTIC having the POOREST prognosis. Glottic lesions do NOT metastasize to the neck, because there are NO lymphatic channels in this area.

Answer 14

Chemotherapy is used to downgrade tumors, making them more amenable for surgery. Agents: Cisplatin and 5-FU Dosage: Cisplatin 50mg/kg/dose 5-FU 50mg/kg/day What to check prior to administration: 1) WBC count 2) BUN/Crea (Nephrotoxic) Administration: IV, ensure patient is well-hydrated prior to starting it - Cisplatin given on Day 1 x 4 hours - 5-FU given for 5 straight days as bolus.

Answer 15

a. marginal mandibulectomy

Answer 16

d. Wide excision

Answer 17

c. Completion thyroidectomy should be done

Answer 18

c. Serum calcium and parathormone

Answer 19

Subclavian vein, phrenic nerve, anterior scalene muscle, subclavian artery, middle scalene muscle

Answer 20

Long thoracic nerve

Answer 21

Accessory nerve and the brachial plexus

Answer 22

Sternocleidomastoid, trapezius, and platysma

Answer 23

Hypoglossal nerve

Answer 24

Palatoglossus

Answer 25

Anterior scalene

Answer 26

Temporal, zygomatic, buccal, marginal mandibular, cervical branches

Answer 27

Marginal mandibular nerve

Answer 28

Ophthalmic (V1), maxillary (V2), mandibular (V3)

Answer 29

Cricothyroid muscle

Answer 30

Internal branch of the superior laryngeal nerve

Answer 31

Recurrent laryngeal nerve

Answer 32

STAT: | Suprascapular artery. Transverse cervical artery. Ascending cervical artery. inferior Thyroid artery

Answer 33

Superior thyroid artery

Answer 34

Anterior/posterior ethmoidal arteries off the ophthalmic artery Superior labial artery from the facial artery Sphenopalatine artery off the internal maxillary artery

Answer 35

Ansa cervicalis

Answer 36

``` Level I: submental and submandibular nodes Level II: upper jugular nodes Level III: middle jugular nodes Level IV: lower jugular nodes Level V: posterior triangle Level VI: anterior compartment Level VII: upper mediastinal nodes ```

Answer 37

Facial nerve

Answer 38

Stenson duct

Answer 39

Wharton duct

Answer 40

Greater auricular nerve

Answer 41

Squamous cell carcinoma

Answer 42

Tobacco and alcohol

Answer 43

Nasopharyngeal squamous cell carcinoma

Answer 44

Primary radiation

Answer 45

Submental and submandibular (level I}

Answer 46

Hemangioma

Answer 47

Primary radiation versus conservative surgical resection-laser versus endoscopic (if recurs, perform cordectomy)

Answer 48

Laryngectomy, modified radical neck dissection, and postoperative radiation

Answer 49

Plummer-Vinson syndrome

Answer 50

Clinically positive lymph nodes Fixed cervical mass High rate of suspicion for metastatic disease

Answer 51

Clinically positive nodes Bone invasion Tumor size >4 cm

Answer 52

``` Accessory nerve, cervical branch of the facial nerve, internal jugular vein, ipsilateral thyroid, omohyoid, stemocleidomastoid muscle, submandibular gland, sensory nerves C2 to C5 ```

Answer 53

Type I: spinal accessory nerve Type II: spinal accessory nerve, internal jugular vein Type III: spinal accessory nerve, internal jugular vein, sternocleidomastoid (SCM)

Answer 54

Pleomorphic adenoma

Answer 55

Warthin tumor

Answer 56

Hemangioma

Answer 57

Mucoepidermoid carcinoma

Answer 58

Adenoid cystic carcinoma

Answer 59

Very sensitive to radiation; therefore, it can be considered as the treatment modality, although resection is the mainstay of treatment.

Answer 60

Kiesselbach plexus

Answer 61

Ethmoid artery, internal maxillary artery

Answer 62

The accumulation of blood in the nasal septum may deprive the septal cartilage of its blood supply from the perichondrium. It requires immediate incision and drainage, septal splinting, and antibiotics to prevent avascular necrosis of the septal cartilage and subsequent saddle nose deformity.

Answer 63

Head elevation Avoid nose blowing/straining With/without antibiotics

Answer 64

B2-transferrin

Answer 65

Surgical repair

Answer 66

Surgical repair

Answer 67

Upper esophagus at the thoracic inlet

Answer 68

Above the third tracheal ring

Answer 69

IV antibiotics and needle aspiration

Answer 70

IV antibiotics and surgical drainage through the posterior pharynx or neck

Answer 71

IV antibiotics, incision and drainage through the lateral neck, and leave a drain in place

Answer 72

Antibiotics, IV fluids, sialogogues, warm compresses

Answer 73

When there is no clinical improvement after 12 hours of treatment

Answer 74

Answer: D. The cricothyroid muscle is the only muscle of the larynx innervated by the external branch of the superior laryngeal nerve. All other laryngeal muscles are innervated by the recurrent laryngeal nerve.

Answer 75

Answer: D. The afferent limb of the gag reflex comes from the glossopharyngeal nerve (cranial nerve IX).

Answer 76

Answer: B. Most neck masses in males over the age of 60 are a result of metastatic spread from cancers in the chest and abdomen. These cancers frequently metastasize via lymphatic spread, and the most common location for the neck mass is within the supraclavicular fossa.

Answer 77

Answer: C. Pleomorphic adenomas are the most common benign salivary gland tumors, comprising 85% ofall salivary gland neoplasms. Tumors of the parotid gland are the most common of the salivary gland tumors, with a 5 times higher incidence than tumors of the minor salivary glands. The vast majority of tumors of the parotid gland are benign in nature.

Answer 78

Answer: E. The physical examination reveals findings consistent with a nasal septal hematoma. The most common complication of this condition is a saddle nose deformity as a result of avascular necrosis from an infected septal hematoma.

Answer 79

Answer: D. A radical neck dissection includes removal of all the ipsilateral lymph nodes from levels I through V along with the spinal accessory nerve, the sternocleidomastoid muscle, and the internal jugular vein. A modified radical neck dissection removes all the lymph nodes but preserves one or all of the non-lymphatic structures.

Answer 80

Answer: E. A Warthin tumor is the second most common benign tumor of the parotid gland. It has an extremely low rate of malignant transformation (0.3%), as well as a low risk of recurrence (1.8% after local excision). The treatment is superficial parotidectomy, sparing the facial nerve. Simple enucleation is avoided because it increases the risk of recurrence and facial nerve injury.

Answer 81

Answer: C. The next step in the workup includes an FNA and MRI of the head and neck. Given the patient's age and symptoms, tissue diagnosis is required for definitive diagnosis, and MRI is necessary to evaluate the extent of disease. Local spread is common, but the incidence of metastatic disease with malignant salivary gland tumors is rare.

Answer 82

Answer: C. Gustatory sweating following parotidectomy is known as Frey syndrome. Injury to the auriculotemporal nerve can occur during parotid surgery. The auriculotemporal nerve carries sympathetic fibers to the sweat glands of the scalp and parasympathetic fibers to the parotid gland. Following injury and subsequent regeneration, the fibers can cross-innervate, leading to gustatory sweating.

Answer 83

Answer: A. First branchial cleft cysts typically originate at the angle of the mandible and often extend to the external auditory canal. Second branchial cleft cysts are found along the anterior border of the sternocleidomastoid muscle and connect with the tonsillar pillar.

Answer 84

Answer: C. The hypoglossal nerve runs about 2 cm above the carotid bifurcation and is the motor nerve of the tongue, except for the palatoglossus. The tongue would deviate to the same side of the hypoglossal nerve injury. Hoarseness and an inability to make high-pitched sounds are the result of injury to vagus nerve branches, namely the recurrent laryngeal and superior laryngeal nerve, respectively.

Answer 85

Answer: C. This is a classical description of Ludwig angina, which is an acute infection of the floor of the mouth. It can rapidly spread to deeper structures and create an airway emergency. Securing the airway, as in the presented case, would be the first step. All the other choices would come next, with surgical drainage and antibiotics in the majority of cases.

Answer 86

Answer: D. No pertinent clinical information is provided in the question. History and physical exam is the first step in any case, including board scenarios. All other choices are possibilities, depending on what direction the history and physical exam point to.

Answer 87

Answer: C. A rule-of-thumb for repair of the cleft lip is at 10 weeks, 10 lb, and hemoglobin of 10 g/dL. The nasal deformity is also repaired at the same time. Cleft palate is usually repaired at 12 months to avoid the negative effect of the maxillofacial growth.

Answer 88

Answer: A. Epiglottitis is rarely seen in the United States due to immunization against H. influenzae type B. Its prevalence has recently increased due to parental refusal of immunization of their children. It is mainly seen in children of 3 to 5 years of age. It can cause airway obstruction and become an emergency. The mainstay of treatment is antibiotics after securing the airway.

Answer 89

ANSWER: B COMMENTS: The left RLN separates from the vagus in the mediastinum, wraps around the aortic arch at the ductus arteriosus, and then ascends back along the tracheoesophageal groove toward the larynx. The right RLN divides off the vagus and passes around the right subclavian artery to travel to the larynx. The RLN supplies all the muscles of the larynx except the cricothyroid muscle, which is innervated by the external branch of the superior laryngeal nerve. The superior laryngeal nerve also has an internal branch that supplies sensation to the larynx above the true vocal cords. The RLN provides sensation below this area. The vagus nerve exits the skull base on both sides through the jugular foramen, not the carotid canal. The internal branch of the superior laryngeal nerve, not the RLN, enters the thyrohyoid membrane. The RLN travels along the tracheoesophageal groove and enters the larynx just superior to the cricoid cartilage. Nonrecurrent nerves occur most commonly on the right side in up to 1%–2% of patients and can be associated with a retroesophageal right subclavian vein.

Answer 90

ANSWER: B COMMENTS: Head and neck carcinogenesis is a complex process with multiple etiologic factors and a wide variety of genetic alterations that have been identified. The incidence of second primary tumors in head and neck cancers is not insignificant (3%–7%), and they should be surveyed for in the upper aerodigestive tract, esophagus, and lung at the time of initial diagnosis. Synchronous versus metachronous lesions are defined in relation to the time of diagnosis from the initial discovery of the tumor; synchronous lesions are found within 6 months, with metachronous lesions being diagnosed after 6 months. In recent years, HPV has been identified as an etiologic factor in certain head and neck cancers, specifically the oropharynx. Protooncogenes are genes that produce proteins involved in the normal cell regulation and function. Mutation of these genes, including those for epidermal growth factor receptor (EGFR), cyclin D1, and vascular endothelial growth factor, occurs in head and neck cancers. Tumor suppressor genes such as p53 and p16-ARF encode proteins that halt tumor growth and carcinogenesis. Cetuximab is a novel monoclonal antibody therapy that has been designed to target EGFR. Trials are ongoing regarding its efficacy in combination with standard treatments such as radiotherapy and chemotherapy. Mutated p53 is poorly degraded and therefore commonly overexpressed in head and neck cancers. It is the most commonly altered tumor suppressor gene in human cancers, with p16-ARF being the most commonly altered gene locus in head and neck cancers.

Answer 91

ANSWER: B COMMENTS: The lip begins at the vermilion border and is a subsite of the oral cavity. Risk factors for lip carcinoma include sun exposure and tobacco use. The lower lip is by far the most common site of tumor development, with SCC being the most common pathology. Basal cell carcinoma is the most frequent pathology found on diagnosis for upper lip cancers. Initial evaluation should include testing for mental nerve involvement, evaluation for man- dibular invasion, and examination of the cervical lymphatics. CT can be useful, especially in staging the mandible and cervical nodes. Treatment of the early-stage disease can consist of either primary external beam radiation or surgical resection. Primary excision is typically the favored treatment. An elective lymph node neck dissection for a clinically negative neck is performed in patients with advanced T stage disease or in the setting of deep tumor invasion in which the risk for occult cervical lymph node disease is elevated. Therapeutic neck dissection is appropriate in patients with positive nodal disease. Indications for postoperative irradiation include advanced T stage, positive margins, perineural/ perivascular invasion, multiple or bulky nodal disease, and invasion of bone. Fortunately, given its location, many lip cancers are detected early and can be treated with a high success rate. Stages I and II lesions have a 90% 5-year survival rate. The survival rate drops to about 50% in patients with cervical lymph node involvement. Reconstructive options following the excision of carcinoma of the lip generally depend on the location of the lesion (medial versus lateral with the involvement of the oral commissure) and the size of the defect. Smaller lesions that involve less than a third to half of the lip can be closed primarily with the local advancement of the tissue. Larger defects involving between half and two-thirds of the lip will probably require donated tissue such as a pedicled two- stage cross-lip transfer flap. An Abbe flap is used for central defects, whereas Estlander-style flaps are used for lateral defects. Larger defects can be repaired with local advancement techniques, local rotational flaps, or distal free flaps.

Answer 92

ANSWER: D COMMENTS: This is a case of classic “sentinel” bleeding that occurs before the full rupture of the innominate artery. It can occur with a low tracheostomy or a high innominate artery with the erosion of the anterior tracheal wall as a result of pressure necrosis. Fiberoptic examination of the area should be performed to evaluate the situation. If there is an obvious evidence of erosion, the patient might need a sternotomy and mediastinal exploration. If the index of suspicion is lower or the examination is inconclusive, diagnostic imaging with a high-resolution CT or angiography (or both) may be appropriate. This complication carries an extremely high mortality rate if massive bleeding occurs. Attempts to control active bleeding can consist of direct digital pressure or inflation of a cuffed tube directly over the area for tamponade. Any of the other choices would not cause rapid-onset bright red bleeding. Bleeding from the anterior jugular veins usually occurs immediately in the postoperative setting if they were not ligated adequately during surgery. Other complications of tracheostomy in the early period include infection, pneumothorax, bleeding, and tube obstruction. Later complications can include wound breakdown, formation of granulation tissue, tracheal stenosis, tracheoesophageal fistula, and tracheoinnominate fistula, as just described.

Answer 93

ANSWER: A COMMENTS: A carotid body tumor is the most common paraganglioma in the head and neck. Other paragangliomas that occur in this region include the vagal and jugulotympanic types. The majority of paragangliomas are solitary and nonfamilial. Multicentricity is reported in about 10% of cases, with about a 6% rate of malignancy. Only about 1%–3% of them are considered functional and can be evaluated with a 24-h urine collection for the analysis of catecholamines. The “Fontaine sign” refers to mobility in only the lateral direction on palpation, whereas pain occurring with chewing is called “first-bite syndrome.” Histopathologic evaluation of this tumor demonstrates two types of cells: type I, chief cells/granular cells, and type II, sustentacular supporting cells. Unlike most head and neck tumors, malignancy is not diagnosed by the presence of dysplastic changes in the primary tumor. The presence of a metastatic disease either to the regional cervical lymphatics or to the distant sites is the only diagnostic criteria. Imaging is the major modality for primary diagnosis since needle biopsy is contraindicated. CT will show a hypervascular mass at the carotid bifurcation, with magnetic resonance imaging (MRI) demonstrating a classic “salt and pepper” appearance on T2-weighted sequences because of hemorrhage and flow voids. On angiography, the internal and external carotid arteries will be bowed apart, a finding referred to as the “lyre sign.” These tumors are best treated surgically, and vascular reconstruction may be necessary. Radiation therapy can stop the growth of these lesions but not shrink their size. Patients should be aware of the potential risk of injury to the vagus.

Answer 94

ANSWER: B COMMENTS: The pharynx is lined by both nonkeratinizing strat- ified squamous epithelium and ciliated respiratory epithelium. The Waldeyer ring consists of the palatine tonsils, adenoids, and the lingual tonsils, which lie along the base of the tongue. The palatine tonsils have crypts lined by stratified squamous epithelium. The adenoids are covered by pseudostratified ciliated columnar epithelium with surface folds but, unlike the tonsils, do not have crypts. The tonsillar crypts are designed to trap foreign antigens for presentation to the lymphoid follicles. The nasal cavity is composed primarily of respiratory epithelium but also contains specialized sensory olfactory epithelium along the roof. Hundreds of minor salivary glands lie in the submucosa of the oral cavity and pharynx.

Answer 95

ANSWER: D COMMENTS: This patient has Ludwig angina, probably sec- ondary to an odontogenic infection given the history of tooth pain. This condition involves a rapidly evolving soft tissue cellulitis that spreads through the fascial planes of the sublingual space, submandibular space, and anterior aspect of the neck. It can cause severe swelling of the floor of the mouth and tongue and possibly airway obstruction. Initial management in this patient should involve securing his airway. An emergency cricothyrotomy would be appropriate in the emergency department if the patient was currently decompensating and exhibiting obstruction and needed an airway immediately. He is ventilating well but drooling and posturing forward. This patient should be taken to the OR expedi- ently to perform fiberoptic intubation and a possible tracheostomy under controlled circumstances. At that point, CT could be performed to evaluate for an abscess collection. Exploration of the neck at the bedside, especially without securing the airway, is unsafe and not appropriate. Tonsillitis is the most frequent cause of deep tissue neck infections in children with odontogenic sources, and an IV drug injection is a more common cause in adults. Peritonsillar abscesses are the most commonly encountered sequelae. Classic signs and symptoms include drooling, hot potato voice, otalgia [from irritation of cranial nerve (CN) IX], and unilateral swelling of the soft palate with uvular deviation to the opposite side. Treatment includes drainage by transoral needle aspiration or incision and drainage with a scalpel blade. A para- pharyngeal space abscess can manifest in a similar fashion to a peritonsillar abscess as severe throat and neck pain but without the appearance of soft palate/peritonsillar swelling. The tonsil may appear medially. It is adjacent to many of the other spaces and can allow spread along the carotid sheath (“Lincoln highway of the neck”) or damage to CNs IX to XII. Drainage is generally performed in a transcervical fashion if necessary. Retropharyngeal space abscesses are more common in young children and require some clinical suspicion to detect. Initial signs may include fever, lack of appetite, cervical adenopathy, and torticollis. This area can usually be approached transorally if the infection is limited but may require transcervical drainage. CT is mandatory to define its extent and to aid in planning access. The retropha- ryngeal space extends from the skull base to the mediastinum. The retropharyngeal space has a midline raphe that causes unilateral shifting, whereas the prevertebral space does not, with these collections appearing more midline.

Answer 96

ANSWER: E COMMENTS: The T classification as defined by the American Joint Committee on Cancer (AJCC) refers to the primary tumor. Carcinoma of the oral cavity is staged according to size. T2 lesions are 2 to 4 cm, as in this patient. Oral cavity T staging is as follows: T1, less than 2 cm; T2, 2 to 4 cm; T3, greater than 4 cm; and T4, invasion of adjacent structures. Clinical staging of the neck has been made more accurate by high-resolution imaging (CT). Had this node been ipsilateral, it would have been staged as N1. However, since it is contralateral to the primary disease, it is classified as N2c. Table 30.1 applies to primary tumors of the oral cavity, oropharynx, hypopharynx, and larynx: NX Regional lymph nodes cannot be assessed N0 No regional lymph node metastasis N1* Metastasis in a single ipsilateral lymph node, 3 cm or less in greatest dimension N2* Metastasis in a single ipsilateral lymph node, more than 3 cm but not more than 6 cm in greatest dimension; or in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension; or in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension N2a* Metastasis in a single ipsilateral lymph node more than 3 cm but not more than 6 cm in greatest dimension N2b* Metastasis in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension N2c* Metastasis in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension N3* Metastasis in a lymph node more than 6 cm in greatest dimension *Note: A designation of “U” or “L” may be used for any N stage to indicate metastasis above the lower border of the cricoids (U) or below the lower border of the cricoids (L). Similarly, clinical/radiological extracapsular spread (ECS) should be recorded as E− or E+, and histopathologic ECS should be designated as En, Em, or Eg. .

Answer 97

ANSWER: B COMMENTS: FNAB is not contraindicated for parotid mass diagnosis. Large-bore needle biopsies have an increased risk of tumor seeding. FNAB has low false-negative and -positive rates, and malig- nancy detection is high. It is effective in lymphoma diagnosis and should be performed with a 21- to 25-gauge needle. FNAB specimens should not be placed in saline as it is a nonphysiologic medium. FNAB has become the standard technique for the initial office evaluation of a neck mass due to the technique’s high diagnostic accuracy. The technique reliably can differentiate between reactive and inflammatory processes not requiring surgery from neoplasia as well as between benign and malignant tumors. The overall diagnostic accuracy is approximately 95% for all masses in the head and neck including 95% for benign lesions and 87% for malignant lesions. If the result is nondiagnostic, which occurs approximately 10% of the time, the FNAB can easily be performed again or an excisional biopsy can be performed if indicated. FNAB is additionally useful in the diagnosis of lymphoma. Immunotyping can be performed on FNAB specimens that can detect surface antigens and cell lineage (T cell or B cell) and can confirm the presence of monoclonal light or heavy chains. Even if the FNAB cannot absolutely confirm lymphoma, it typically still rules out SCC and thus would lead the surgeon to a possible open biopsy of the mass to further evaluate for lymphoma rather than pursue a workup of head and neck SCC, which would include laryngoscopy and esophagoscopy to search for a primary tumor. The FNAB technique is typically performed in the office setting under local anesthesia, with the application of 1% lidocaine with epinephrine. A 21- to 25-gauge needle on a 10- to 20-mL syringe is then inserted into the mass and moved in and out of the mass in short vibratory strokes of 2 to 3 mm while aspirating on the syringe. These vibratory strokes continue until cellular material enters the needle hub at which point the needle is removed from the mass. This process is repeated at least twice and as many as four times according to the literature. Pressure should then be held on the mass to stop bleeding and a bandage applied. The aspirated material can either be expelled directly onto slides and taken to a pathologist or fixed directly in CytoLyt. The advantage of placing the material directly on slides is that the specimen does not need to be spun down, and analysis with microscopy can begin immediately.

Answer 98

ANSWER: B COMMENTS: Any adult patient with a new onset of unilateral middle ear effusion and no related history of recent upper respira- tory illness should undergo evaluation of the nasopharynx. Another clinical clue in this patient is the presence of a level V node, which is a common location for cervical metastasis from nasopharyngeal cancer. This is especially true in this patient given his history of a southern Chinese background. This area, particularly the Guangdong Province, has an increased incidence of nasopharyngeal carcinoma. The etiologic factors are multifactorial and include genetic and environmental factors. Infection with Epstein-Barr virus (EBV) has been shown to have an etiologic role. In addition, dietary factors, including the intake of salted fish, have a strong association with the development of this disease. Nasopharyngeal carcinoma is divided by the World Health Organization into two groups, keratinizing and nonkeratinizing carcinoma, with the second group including both differentiated and undifferentiated subtypes. The diagnosis of nasopharyngeal carcinoma is made using nasopharyngoscopy and biopsy. High serologic levels of immunoglobulin (Ig)A to EBV viral capsid antigen and early antigen are seen in patients with this disease. Nasopharyngoscopy and biopsy has been advocated as a screening tool in high-risk populations based on a study showing a 5.4% diagnosis rate of subclinical nasopharyngeal cancer in patients with elevated IgA levels to EBV who live in the Guangdong Province. Treatment consists mainly of chemotherapy and radiation therapy. Surgery has a limited role in treating nasopharyngeal cancer in patients with limited primary site recurrence and nodal recurrence.

Answer 99

ANSWER: C COMMENTS: Chemotherapy has developed an increasing role over the past two decades in the treatment of head and neck SCCs. For early-stage patients, treatment consists of either radiation therapy or surgery, with chemotherapy having little to no role in the treat- ment. It is never used as a primary single-modality treatment for head and neck cancers with an intent to cure. For patients with advanced metastatic or recurrent disease, chemotherapy can be used in the palliative setting to inhibit tumor growth for a limited effective period. Its main role is in the treatment of locoregionally advanced stage III/IV cancer. A second role of chemotherapy in this group of patients is for organ preservation. Patients with an advanced primary T stage are best served by total laryngectomy. For advanced-stage unresectable tumors, concurrent chemoradiation therapy, compared with radiation therapy alone, has shown an improved locoregional control with a questionable overall survival benefit.

Answer 100

ANSWER: C COMMENTS: Neck dissection involves the removal of the cervi- cal lymphatic tissue and related structures for the treatment of head and neck cancers. Radical neck dissection involves removing all of the cervical lymphatic tissue in neck levels I through V, in addition to removing the internal jugular vein, SCM muscle, and spinal accessory nerve. A modified radical neck dissection is performed for the same clinical indications as a radical neck dissection. The differentiating feature is that it preserves at least one of the follow- ing: the internal jugular vein, SCM muscle, or spinal accessory nerve. Levels I through V lymph nodes are removed as for a tradi- tional radical neck dissection. However, it is frequently possible to preserve one of the major structures just listed, especially when it is not involved with tumor. Particularly in the case of the spinal accessory nerve, this is preferable to prevent postoperative shoulder dysfunction from denervation of the trapezius muscle. The patient in this scenario will most certainly need postoperative physical therapy due to CN XII resection. Selective neck dissection is used for removing a limited number of lymph node levels, as opposed to resecting levels I through V. Furthermore, the internal jugular vein, SCM muscle, and CN XII are preserved. The philosophy behind performing this type of dissection is to remove the clinically uninvolved lymphatic groups thought to be most at risk for future metastatic disease. Therefore the type of dissection is predicated on where the primary tumor is located. Oral cavity cancers typically metastasize to levels I, II, and III. These levels would be included in what is termed a supraomohyoid selective neck dissection. Laryngeal, hypopharyngeal, and oropharyngeal cancers commonly spread to levels II, III, and IV, which would be incorporated into a lateral selective neck dissection. Posterolateral neck dissection (levels II, III, IV, and V) is most commonly used in the setting of cutaneous malignancies involving the posterior region of the scalp. Sentinel lymph node biopsy is under investigation for its efficacy in SCC of the head and neck. It is currently used in the management of cutaneous melanoma of the head and neck. However, the internal carotid artery is not considered a standard part of the routine neck dissection, and there is controversy regarding the utility and benefit of resection. The phrenic nerve is at risk when dissecting along the floor of the neck. A level VI or central compartment dissection is not part of a standard radical neck dissection. It is typically used in patients with thyroid tumors, tracheal tumors, or laryngeal cancers with extensive subglottic extension. Therapeutic neck dissection has been used to treat positive metastatic cervical disease (N+) through either a radical or a modified radical neck dissection. Currently, some surgeons are beginning to advocate the use of a more limited selective neck dissection if the patient has limited N1 disease. In addition to being used as primary treatment, it also can be used as salvage treatment after failed nonsurgical therapy, such as external beam radiation. For patients with clinically negative disease in the neck (N0), elective neck dissection can be performed to target the most likely sites of metastatic drainage. Such dissection is based on the primary site of the tumor. Sentinel lymph node biopsy in the treatment of SCC of the head and neck is currently under investigation and not yet advocated widely as a proven standard of care.

Answer 101

ANSWER: A COMMENTS: This patient has a venous air embolism as a result of the internal jugular vein being inadvertently opened. With all surgeries above the heart, there is a risk for air embolism. This is especially true in neurosurgical procedures, where there is signifi- cant elevation of the wound relative to the heart. In head and neck surgery, patients are typically placed in the reverse Trendelenburg position, which places them at an additional risk for entrance of air into the venous system. A “mill-wheel murmur” is the traditional finding on cardiac examination and may be detected on precordial Doppler ultrasound. The clinical manifestations can include cardio- vascular, pulmonary, and neurologic findings. Cardiac findings can include tachyarrhythmias, right-sided heart strain, and myocardial ischemia. Pulmonary findings can include hypercapnia with decreased O2 saturation. A decreased cardiac output results in decreased cerebral perfusion, but a direct air embolism to the central nervous system can occur through a patent foramen ovale. Initial treatment involves placing the patient in the left lateral decubitus position (Durant position) to try to force the air to stay in the right side of the heart in an attempt to prevent it from traveling into the pulmonary circulation. Placement of a central venous catheter with aspiration of air from the right atrium can also be attempted. Other supportive efforts may need to include cardiopulmonary resuscitation if the situation deteriorates. Hyperbaric oxygen therapy has been shown to be of benefit in some studies.

Answer 102

ANSWER: C COMMENTS: The causative organisms are most commonly Mucor, characterized by nonseptate hyphae with a 90-degree branching pattern, and Aspergillus, characterized by septate hyphae with a 45-degree branching pattern. This disease is fatal in 50%–80% of patients. The pathophysiology is characterized by the fungal organism invading the soft tissues and bone, causing vascu- lar occlusion, infarction, and tissue necrosis. This disease occurs almost exclusively in immunocompromised patients (those with diabetic ketoacidosis, undergoing chemotherapy, with bone marrow transplant) and can occur in those with qualitative deficiency (e.g., diabetic ketoacidosis) as well as quantitative deficiency (chemo- therapy, acquired immunodeficiency syndrome). The gold standard for diagnosis is histopathology. Invasive fungal sinusitis is characterized by mucosal invasion of mycotic organisms and by angioinvasion, leading to tissue necrosis and potential for invasion into nearby structures such as the orbit and brain. The population at risk includes immunocom- promised patients. Typical presenting symptoms include neutrope- nic fever, nasal congestion, vision change, V2 numbness, and soft tissue swelling. Physical examination may yield periorbital skin necrosis or blackened eschar of the hard or soft palate. Nasal endoscopy is characterized by mucosal changes of nasal structures such as the septum and middle turbinate. The mucosa can appear pale or may be covered by a gray or black eschar. Nasal mucosa is often insensate in these patients and does not bleed. Treatment requires an urgent surgical debridement, often coupled with a long-term IV antifungal therapy. Histopathology is the gold standard for diagnosis. Fungal culture can be used as an adjunct, but it is less sensitive and may take weeks to provide a diagnosis, which results in decreased utility in such an acute and life-threatening disease process.

Answer 103

ANSWER: D COMMENTS: The facial nerve is found 1 cm anterior, inferior, and deep to the tragal cartilage (tragal pointer). Frey’s syndrome is the result of an injury to the auriculotemporal nerve, which results in an aberrant innervation of cutaneous sweat glands by postgan- glionic parasympathetic fibers. Injury to the greater auricular nerve causes numbness to the skin overlying the mastoid bone and portions of the pinna. The parotid gland is divided into superficial and deep lobes by the retromandibular vein. Facial nerve identification is crucial while performing paroti- dectomy in order to preserve its integrity and function. The facial nerve can be identified by utilizing multiple landmarks. • Tragal pointer: The facial nerve is 1 cm anterior, inferior, and deep to the tragal cartilage. • Tympanomastoid suture line: The facial nerve is 6 to 8 mm deep to the inferior edge of the tympanomastoid suture line. • The digastric tendon insertion point onto the digastric ridge defines the plane of the facial nerve. • The facial nerve main trunk can additionally be identified exiting the skull base at the stylomastoid foramen or, alternatively, can be found by performing retrograde dissection after finding a distal branch. There are numerous potential complications of parotidectomy. First, facial nerve injury can occur and would result in facial paresis or paralysis on the affected side. If this is identified intraoperatively, the nerve should be immediately repaired. Second, greater auricular nerve hypoesthesia can be the result of a traction injury or transection. This results in periauricular numbness and typically resolves within 9 months if not deliberately transected. Third, salivary fistulas can occur and typically resolve in 2 to 3 weeks. Fourth, Frey’s syndrome occurs as a result of injury to the auriculotemporal nerve (which contains sympathetic fibers) and results in an aberrant innervation of cutaneous sweat glands by postganglionic parasympathetic fibers. It presents as sweating and reddening of the skin during meals. Other complications include hematoma, infection, and flap necrosis.

Answer 104

ANSWER: B COMMENT: The depth of invasion and ulceration are key factors of the TNM staging system, but the regional nodal status is the most powerful predictor of survival for patients with malignant melanoma of the head and neck. T staging takes into account the depth of invasion, not Clark levels. Sentinel lymph node biopsy has become the approach to the initial evaluation of the regional nodal status, not elective neck dissection. Mitotic rate plays a role in TNM staging. The classic finding that raises suspicion for malignant mela- noma is the presence of a pigmented lesion that changes over the course of weeks to months. Change in diameter, border irregularity, color change, ulceration, itching, pain, and bleeding are all signs that should raise suspicion for melanoma. Excisional biopsies are the favored method to elucidate diag- nosis, while incisional or punch biopsies are acceptable alternatives if there are anatomic or cosmetic constraints. If biopsy is positive for an invasive melanoma, even if accomplished by an excisional biopsy with negative margins, further resection of the primary site with larger margins is necessary. T staging is based on thickness, presence of ulceration, and mitotic rate. N status is based on the regional nodal status, which, as previously stated, is the most powerful predictor of survival in patients with malignant melanoma of the head and neck. The decision to evaluate the regional nodes is based on the characteristics of the primary tumor and the risk of nodal metastasis. Patients with T1 lesions have a 3% risk of metastasis to a sentinel lymph node; T2, 8%–12%; T3, 23%–27%; and T4, 24%–44%. Patients with lesions that are 0.75 mm or less in depth do not require evaluation of regional nodes, and observation is appropriate for them. Patients with lesions between 0.76 and 1.0 mm in depth without ulceration and less than 1 mitosis/mm2 should consider sentinel lymph node biopsy. Patients with lesions between 0.76 and 1 mm in depth with ulceration or greater than 1 mitosis/mm2 or with lesions greater than 1 mm in depth should be recommend a sentinel lymph node biopsy.

Answer 105

ANSWER: B COMMENT: The facial nerve is at risk during the excision of the first BCA. The second BCA is characterized by a neck mass at the anterior edge of the SCM and has a tract that runs between the internal and external carotid arteries, passes superior to the glossopharyngeal and hypoglossal nerves, and finally ends at the tonsillar fossa. Second BCAs are the most common anomaly. The second BCA cannot be differentiated from the third and fourth BCAs on the basis of position of SCM alone. All three anomalies have a lesion anterior to the SCM. They are differentiated based on the path of their tracts. Moreover, 90% of the third BCAs occur on the left side. BCAs are common in the pediatric population and are a result of the failure of involution of embryonic structures. These anomalies may remain asymptomatic, not appreciable on physical examination, and often do not require treatment. Alternatively, these anomalies can enlarge, which can raise concern for neoplastic process; can become secondarily infected; or can cause cosmetic deformity. These are all possible indications for surgical excision. There are four types of BCAs. Each may be associated with a characteristic deep tract. If the deep tract is incompletely excised, there is an increased risk for recurrence. The first BCA is not common. It characteristically has a mass located near the lobule of the ear. A CT or MRI is critical to differentiate this lesion from dermoid cysts, lymphatic malformations, parotid masses, or other tumors. The first BCAs typically appear as fluid-filled cystic lesions on CT. During a surgical excision, it is vital to remember that the cyst may have a deep component that may pass either lateral or medial to the facial nerve, which must be identified in the entire first BCA lesion, and is to be safely removed. The second BCA is the most common of the brachial cleft lesions, and it is characterized by a lesion at the anterior border of the SCM. Its deep tract runs between the internal and external carotid arteries, superior to the glossopharyngeal and hypoglossal nerves, and ends in the tonsillar fossa. The third BCA is also characterized by a lesion at the anterior border of the SCM. Its associated tract passes posterior to the internal and external carotid arteries, between the glossopharyngeal and hypoglossal nerves, and terminates at the apex of the pyriform sinus. The fourth BCA additionally presents as a lesion at the anterior border of the SCM. Its tract runs from the apex of the pyriform sinus and travels inferiorly in the tracheoesophageal groove; then, it runs posterior to the thyroid gland and into the thorax where it loops below the aorta on the left and below the subclavian artery on the right. It then ascends posterior to the common carotid artery and loops over the hypoglossal nerve, ending at the anterior border of the SCM. The spinal accessory nerve exits the skull base via the jugular foramen and enters level II by passing anterior to the jugular vein but deep to the posterior belly of the digastric muscle and the SCM. The nerve heads in a posteroinferior direction and gives off a branch to the SCM before entering the substance of the SCM and exiting deep to Erb’s point (the point where the greater auricular nerve sweeps around from the posteroinferior aspect of the SCM) and traverses level V in a superficial plane before innervating the trapezius muscle. For these reasons, CN XI injury risk is the highest while dissecting lesions deep to the SCM and during a level V dissection.

Answer 106

ANSWER: C COMMENTS: The patient likely has a bilateral vocal cord paralysis with both true vocal cords found in the paramedian position due to a bilateral RLN injury sustained during a thyroidectomy. The patient is saturating well on nasal cannula; therefore a flexible laryngoscopy would not be contraindicated. The laryngeal neuromuscular anatomy is key to understanding the vocal cord position. The laryngeal musculature can be classified into two groups: abductors and adductors. Adductors include lateral cricoarytenoid muscle, thyroarytenoid muscle, cricothyroid muscle, and the interarytenoid muscle. There is only one abducting muscle: the posterior cricoarytenoid muscle. There are only two nerves that supply motor innervation to these muscles: the RLN and the external branch of the superior laryngeal nerve. The RLN is responsible for innervating each one of the aforementioned muscles, except the cricothyroid muscle, which is supplied by the external branch of the superior laryngeal nerve. Therefore when a vocal cord is paralyzed due to iatrogenic trauma to the RLN, innervation to all the muscles except the cricothyroid, an adductor, is lost. Therefore the true vocal cord sits in an “adducted” position just lateral to midline. This position is called the paramedian position. When there is bilateral true vocal cord paralysis, both cords sit in a paramedian position, which creates a slit-like airway. This results in a significant stridor. However, as the true cords are in proximity to each other, the voice can still be normal. The unilateral vocal cord paralysis typically presents with normal breathing and a normal, breathy, or hoarse voice.

Answer 107

ANSWER: E COMMENTS: Around 75%–80% of parotid tumors are benign. The most common parotid tumor is pleomorphic adenoma. Warthin’s tumor, not pleomorphic adenoma, is seen bilaterally in 12% of patients with a Warthin’s tumor. A surgical biopsy is not recommended due to a high risk of recurrence. Warthin’s tumor is the second most common benign salivary gland tumor and is associated with smoking as a risk factor. Salivary glands are divided into major and minor glands. The major glands include the parotid, submandibular, and sublingual glands. These glands are paired. The minor glands include 600 to 1000 glands found throughout the upper aerodigestive tract. About 70% of salivary gland tumors occur in the parotid gland, of which 75%–80% are benign. The most common benign parotid tumor is pleomorphic adenoma followed next in incidence by Warthin’s tumor, which is associated with smoking and an increased rate of being found bilaterally (12%). The most common malignant neoplasm of the parotid is the mucoepidermoid carcinoma followed by the adenoid cystic carcinoma. Facial paralysis related to a parotid mass should be seen as a concerning sign that the mass is malignant. In malignant neoplasms, pain is typically indicative of neural invasion by the tumor and portends a worse prognosis. However, pain itself is not a predictable indicator of malignancy because benign neoplasms can be associated with pain in the setting of a secondary infection, cystic enlargement, or intralesional hemorrhage. FNA is an accurate and safe aid for diagnosis. It is primarily used to help guide which patients need surgery, rather than to provide a definitive diagnosis. It is very effective in helping to avoid surgery in patients with reactive lymph nodes, lymphoma, or nonneoplastic disorders. Surgical biopsies are not recommended because excisional biopsies and capsule violations are associated with an increased risk of recurrence, even with benign masses like pleomorphic adenoma. The standard surgical approach is to perform a lateral parotidectomy with a cuff of tissue around the mass in addition to the facial nerve dissection and preservation in order to avoid facial nerve injury.

Answer 108

ANSWER: E COMMENTS: Laryngeal cancer is the second most common cancer worldwide. The greatest risk factor for laryngeal cancer remains smoking and drinking; the HPV status is the most important risk factor pertaining to oropharyngeal SCC (OPSCC). The glottis contains the true cords and extends 1 cm inferiorly. The false cords are a supraglottic structure. Sensation to the larynx is supplied by both the internal branch of the superior laryngeal nerve and the RLN. The supraglottis lymphatic drainage tends to be bilateral and to levels II, III, and IV. Epidemiologically, laryngeal cancer is the second most common cancer of the head and neck worldwide, after oropharyngeal cancer. There is a male-to-female preponderance of 6:1. The most important risk factors for the development of laryngeal SCC are smoking and drinking, and these have a multiplicative effect. HPV has also been associated with the development of laryngeal SCC (HPV types 16 and 18) but not as strongly as in OPSCC. Occupational exposure to wood dust, polycyclic hydro- carbons, and asbestos is an additional risk factor. Anatomically, the larynx consists of three subunits: the supraglottis, glottis, and subglottis. The supraglottis extends from the epiglottis to the ventricular apices and encompasses the false cords, aryepiglottic folds, arytenoids, and laryngeal surface of the epiglottis. The glottis consists of the true vocal cords, the anterior commissure, the interarytenoid region, and the floor of the ventricles and extends 1 cm inferiorly below the apex of the ventricle. The subglottis extends from 1 cm below the ventricle to the inferior border of the cricoid cartilage. The blood supply to the supraglottis is delivered via the superior laryngeal artery, which is a branch of the superior thyroid artery. The blood supply to the glottis and subglottis is supplied by the inferior laryngeal branch of the inferior thyroid artery. Lymphatic drainage of the supraglottis is supplied by a rich network. The supraglottis tends to drain to level II but can extend to levels III and IV. Bilateral drainage can occur. The glottis has essentially no lymphatic drainage. The subglottis drains primary to level VI. Sensation above the true cords is supplied by the internal branch of the superior laryngeal nerve, while the sensation of the true cords is supplied by the RLN. The external branch of the superior laryngeal nerve provides motor innervation to the cricothyroid muscle. The RLN is responsible for the motor innervation to the remainder of the laryngeal musculature.

Answer 109

ANSWER: C COMMENTS: A radical neck dissection is defined as the removal of all nodal levels in addition to the SCM, internal jugular vein, and spinal accessory nerve. The transverse process of C2 is an important landmark for the identification of the spinal accessory nerve. The spinal accessory nerve most frequently passes anteriorly to the inter- nal jugular vein in level II. The hypoglossal nerve passes posterior to the internal jugular vein but anterior to the external carotid and its branches. Level III extends from the hyoid bone to the inferior border of the cricoid cartilage. Radical neck dissection is rarely performed today due to significant morbidity such as shoulder droop, an increased risk of facial swelling due to the sacrifice of the internal jugular vein, and an increased risk of carotid blowout due to less superficial tissue coverage after removal of the SCM muscle. It is still performed if there are clinically positive modes with the involvement of the SCM muscle, CN XI, and internal jugular vein. A modified radical neck dissection is defined as the removal of nodes but spares CN IX in type I or CN IX and the internal jugular vein in type II. The selective neck dissection, which is the most commonly performed, does not remove all nodal levels, but specifically those at most risk depending on the site of the primary tumor. The SCM muscle, CN IX, and internal jugular vein are spared. Nodal levels have specific boundaries. Level IA includes the submental triangle and is bound by the anterior belly of the digas- tric muscle bilaterally, the mandible anteriorly, and the hyoid inferiorly. Level IB includes the submandibular triangle and is bound by the anterior belly of the digastric medially, the mandible superiorly, the stylohyoid ligament laterally, and the hyoid bone inferiorly. Level II includes the jugular digastric region from the level of the posterior belly of the digastric down to the hyoid bone. Level II is further divided into B and A segments by the spinal accessory nerve—level IIB is the segment superior and level IIA is the segment inferior. Level III extends from the hyoid bone to the inferior border of the cricoid cartilage. Level IV nodes extend from the inferior border of the cricoid cartilage to the clavicle. Level V is bound by the posterior border of the SCM anteriorly and the anterior border of the trapezius posteriorly. Level IV contains the pretracheal and paratracheal nodes found inferior to the thyroid gland.

Answer 110

ANSWER: B COMMENTS: The upper lip tends to drain ipsilaterally, not bilaterally. The floor of the mouth is composed of the anterior belly of the digastric, the mylohyoid muscle, and the geniohyoid muscle from inferior to superior. The extrinsic muscles of the tongue are responsible for gross tongue movements, while the intrinsic muscles of the tongue are responsible for intricate mobility. The hypoglossal nerve supplies tongue motor innervation. Taste to the anterior two-thirds of the tongue is supplied by the facial nerve via chorda tympani and the lingual nerve while sensation to this part of the tongue is supplied by the mandibular division of the trigeminal nerve. The oral cavity is a complex anatomic space composed of seven distinct subunits. These subunits are important to understand as distinct entities because they each have specific lymphatic drainage pathways and different propensities for local invasion. The oral cavity extends from the vermilion borders of the lips anteriorly to its posterior limit, which is demarcated by the vertical line drawn from the junction of the hard and soft palate to the circumvallate papillae. Laterally, the boundary is the buccal mucosa. The seven subunits are the lips, alveolar ridge, floor of the mouth, oral tongue, hard palate, retromolar trigone, and the lateral buccal mucosa. The arterial supply to the lips is provided by the labial arteries, which are a branch off the facial artery. The lower lip drains to levels IA and IB and tends to have contralateral drainage. The upper lip tends to drain ipsilaterally to level IB, periparotid lymph nodes, and level II lymph nodes. The lower alveolar ridge contains the tooth-bearing component of the mandible. This is a thin bone that tends to involute when dentition is lost. The alveolar ridge blood supply is provided by endosteal and periosteal vessels. Lymphatic drainage is based on the anatomic position. Anterior lesions drain to level I and have bilateral drainage, while lateral lesions tend to drain to the ipsilateral levels IB and II. The floor of the mouth extends from the attached gingiva of the medial alveolar ridge to the muscular tongue and extends posteriorly to the palatoglossus muscle. The primary vascular supply is via the lingual artery and branches of the facial system. The floor of the mouth lymphatic system has superficial and deep drainage pathways. The superficial system drains bilaterally while the deep system drains to ipsilateral level I and the upper jugular chain. The oral tongue consists of three paired extrinsic muscle groups that achieve gross tongue movement: genioglossus, hypoglossus, and styloglossus. The intrinsic musculature includes the lingual muscles as well as the vertical and transverse muscular units, which work together to perform high-fidelity tongue move- ments that assist in speech and swallow. Motor innervation is supplied via the hypoglossal nerve. Taste from the oral tongue is supplied by way of the chorda tympani/lingual nerve system. Lymphatic drainage depends on the anatomic position. Lesions on the tip of the tongue and midline dorsum tend to spread bilaterally as well as to level IA. Lateral oral tongue lesions tend to spread to the ipsilateral level IB and level II. The upper alveolar ridge receives blood supply from the facial artery and internal maxillary artery system. Lymphatic drainage tends to be to ipsilateral level IB, periparotid lymph nodes, and level II. The hard palate tends to drain to levels I and II. It contains three paired foramina that allow for potential tumor spread: the greater palatine, the lesser palatine, and the incisive foramen. The retromolar trigone is a mucosally covered triangular area overlying the ascending ramus of the mandible. The retromolar trigone mucosa is tightly adherent to the mandible; therefore even small mucosal lesions can easily spread to the mandible. Lymphatic drainage is to ipsilateral levels I and II. The lateral buccal mucosa lymphatics drain to levels I and II and periparotid lymph nodes.

Answer 111

ANSWER: E COMMENTS: The patient has a lateralized tongue SCC with an invasion of 4 mm in depth. Adequate margins should be attainable with a partial glossectomy rather than a hemiglossectomy or total glossectomy. This will preserve articulation and swallow function. The patient, even though currently with an N0 neck, is at a high risk of developing cervical metastasis due to a depth of invasion of 4.5 mm. An ipsilateral selective neck dissection is recommended. SCC of the tongue tends to occur in middle-aged males with a history of tobacco and alcohol use. However, there is a subset of patients who tend to be 20 to 40 years of age with no known risk factors. Cancer in this group tends to be more aggressive and carries a poor prognosis despite appropriate therapy. The rate of cervical node metastasis is high, even in T1 or T2 primary cancers. Multiple studies have found that the increasing rate of metastasis is seen in tumors that have a vertical depth of invasion greater than 4 mm. The initial treatment can be surgical or with radiation. A surgical excision is favored for most patients due to the ability to obtain adequate margins while still preserving articulation and the ability to swallow. T1 and T2 cancers can be treated with a partial glos- sectomy with the goal of attaining a 1-cm cuff of normal tissue around the lesion in all directions. T3 and T4 lesions tend to involve adjacent structures such as the floor of the mouth or mandible. These lesions tend to require a hemiglossectomy or total glossectomy to achieve an adequate margin. Further, these patients may require a segmental mandibulectomy or floor of the mouth resection to adequately resect the tumor. Management of the clinically/radiographically N0 neck tends to be more aggressive in even T1/T2 cancers. The reason for this is that even early-stage cancer tends to have a high rate of nodal metastasis, with some studies reporting a rate as high as 30%. If the depth of invasion is 4 mm, a selective neck dissection should be recommended in the clinically/radiographically N0 neck and should even be considered if the depth of invasion is at least 3 mm. Selective neck dissection should include levels I–IV in a clinically/ radiographically negative neck. Level IIB does not need to be dissected unless metastasis is evident intraoperatively.

Answer 112

ANSWER: A COMMENTS: Surgical revision to a formal tracheotomy should be performed due to an increased risk of subglottic stenosis. Laryngotracheal separation is not associated with cricothyroidotomy. Cricothyroidotomy is accomplished by making an incision through the cricothyroid membrane, not the thyroid cartilage. It is contra- indicated in children due to a high risk of cricoid injury and sub- glottic stenosis as well as a low likelihood of successfully entering the airway. Cricothyroidotomy is an important maneuver when intubation is not possible in an emergent setting. It is performed by placing the patient in a supine position with shoulder roll to assist with neck extension. A skin preparation solution is used if time permits. The thyroid cartilage is then grasped between the thumb and second and third fingers of the nondominant hand. A vertical incision is then made with a number 11 or 15 blade to expose the cricothyroid membrane. A vertical incision is made to avoid injury to the anterior jugular veins. Further, it will allow for more exposure of the airway. Once exposed, a horizontal incision is made through the membrane, staying closer to the superior border of the cricoid to avoid injury to the cricothyroid vessels. If avail- able, a tracheal dilator or clamp (Kelly, hemostat, mosquito) can be used to dilate the cricothyroidotomy. If available, a cuffed tracheostomy tube can then be placed through the cricothyroidotomy and a ventilating device attached. Once breath sounds are confirmed, the tracheostomy tube should be secured with sutures, tracheostomy tube ties if available. If no tracheostomy tube is available, any tube that will keep the airway patent and attach to a ventilating system (such as an endotracheal tube) is appropriate. Once secured, the cricothyroidotomy should then be converted to a formal tracheostomy within 48 h due to an increased risk of subglottic stenosis. There is an increased risk because the crico- thyroid space is 7 mm in vertical dimension. Since the cricothy- roid space is usually smaller than the outer diameter of most tracheostomy tubes (6 Shiley disposable cuffed trach tube (DCT) is 10 mm in outer diameter), the risk of cartilage injury is high. A combination of pressure against the cricoid cartilage, shearing forces from the cricothyroid muscle tensing, and concomitant infection create a favorable environment for chondritis, necrosis, and, ultimately, subglottic stenosis.

Answer 113

ANSWER: E COMMENTS: The major risk factors for OPSCC include HPV status, smoking, and drinking. The anatomic subunits of the oropharynx include the soft palate, the tonsillar fossa and pillars, the base of tongue, and the pharyngeal walls, while the epiglottis is a part of the larynx. HPV 16 is the most strongly associated subtype with OPSCC. HPV-positive SCC is commonly identified in OPSCC. Patients with HPV-positive SCC are more responsive to treatment and have a survival advantage. The oropharynx is the middle third of the pharynx and con- nects with the nasopharynx superiorly and hypopharynx inferiorly. Its superior and inferior limitations are defined by horizontal lines drawn through the hard palate and hyoid bone, respectively, while its anterior border is a vertical line drawn through the hard palate/ soft palate junction through the circumvallate papillae. Its posterior border is the posterior pharyngeal wall, which lies anterior to the prevertebral fascia. Its lateral boundary includes the tonsillar fossa and pillars as well as the lateral pharyngeal walls. The oropharynx consists of four subunits: the soft palate, tonsillar fossa and pillars, base of tongue, and pharyngeal walls. Historically, the most important risk factor for the development of OPSCC was exposure to tobacco and alcohol. Smokers have a 5 to 25 times greater risk of developing head and neck cancer than nonsmokers. The relative risk of developing SCC rises to 8.8 in those who consume 30 alcoholic beverages per week compared with a relative risk of 1.2 in those who consume 1 to 4 drinks per week. Smoking and drinking have a cumulative effect: for instance, a patient who has a 40-pack-year smoking history and drinks 5 alcoholic beverages daily has a relative risk of 40. In the last three decades, there has been a demographic shift in the etiologic agent in the development of SCC. HPV is now the most common cause. HPV 16 is the most common detected subtype. HPV-positive tumors are more likely to originate in the oropharynx, be poorly differentiated, and have basaloid features. They tend to occur in younger and healthier patients and tend to present with a lower T stage but a higher N stage. HPV-positive tumors are independently associated with sexual behavior and marijuana use in some studies. These patients have a greater response to treatment and have a survival advantage compared with HPV-negative tumors.

Answer 114

ANSWER: D COMMENTS: The patient has a history and physical examination consistent with SCC of the larynx. The diagnosis should be obtained with a biopsy. Furthermore, CT scans must be obtained to determine the extent of the patient’s disease and to determine staging. However, the primary act in management must be to secure the patient’s airway in as safe a manner as possible. The best option for this patient is to undergo an awake tracheotomy. Putting the patient to sleep prior to an attempted intubation would not be recommended as his obstructing laryngeal mass would likely prevent him from being ventilated via bag mask ventilation. Further, an obstructing mass would make it very difficult to pass an endotracheal tube successfully. Laryngeal cancer commonly presents with dysphonia and odynophagia. Clinicians must also be suspicious if an adult patient presents with odynophagia or ear pain that is present for more than 2 to 3 weeks. Ear pain is a common presenting sign due to referred pain from the throat via Jacobson’s nerve and Arnold nerve. Jacobson’s nerve, a branch of CN IX, directly innervates the ear but also has pharyngeal, lingual, tonsillar, parapharyngeal space, and retropharyngeal space innervation. Any pathologic process involving these areas can result in referred otalgia. Arnold nerve, a branch of CN X, supplies the vallecula, lingual, and laryngeal surfaces of the epiglottis, supraglottic larynx, and pyriform sinuses. The Arnold nerve also directly innervates the ear, which can result in referred otalgia.

Answer 115

ANSWER: A COMMENTS: The image is of a pectoralis myocutaneous flap based on the pectoral branch of the thoracoacromial artery. The thoracodorsal artery supplies the latissimus dorsi myocutaneous flap. The perforating vessels of the occipital artery supply the supe- rior one-third of an SCM myocutaneous flap. The superficial temporal artery supplies the temporoparietal fasciocutaneous flap. The perforating vessels of the internal mammary artery supply the deltopectoral fasciocutaneous flap. Patients undergoing a total laryngectomy require a pharyngeal closure. In patients who have not previously received radia- tion, this can typically be done primarily. However, in patients who have received radiation, the local vasculature is tenuous and these patients are at a higher risk of breakdown of the pharyngeal closure without bolstering the pharyngeal closure with healthy tissue. The pectoralis major flap is a regional pedicled flap that is used frequently for its reliability and excellent reach (can reach up to midface, some report to lateral canthus). Its blood supply is from the pectoral branch of the thoracoacromial artery.

Answer 116

ANSWER: E COMMENTS: In the reconstruction of a segmental mandibulectomy, the surgeon must reconstruct the mandible using the strong bone. A radial forearm osseocutaneous flap provides a bone, but the bone is thin. The latissimus, anterolateral thigh, and gracilis flaps cannot be harvested with a bone and cannot be used to repair a mandibular defect. The best option for reconstruction is the fibula osseocutaneous free flap. The free fibular graft provides the longest possible segment of revascularized bone (up to 25 cm). It can span nearly any mandibular defect. The flap is supplied by the peroneal artery and accompanying veins.

Answer 117

ANSWER: A COMMENTS: A direct laryngoscopy and esophagoscopy would be the next appropriate step. Any suspicious lesions should be biopsied. If no obvious primary site is found during this examination, a right tonsillectomy should be performed and a left tonsillectomy considered. A base of tongue resection would not be indicated at this stage in the patient’s workup. However, a PET scan can be useful; anatomic studies such as CT soft tissue neck or MRI neck should be obtained to fully evaluate for any suspicious lesions. A CT chest with IV contrast should also be obtained to assess for any metastatic disease. P16 positivity would indicate the HPV status. Patients presenting with a head and neck cancer of unknown primary make up about 2%–9% of all patients with head and neck cancer. The diagnosis of a primary tumor is of crucial significance because surgical and oncologic management of the primary lesion may be efficiently coordinated with the management of the neck disease that has improved the survival rates from 44% up to 100%. Further, the type and degree of treatment change based on whether a primary tumor is found. The typical diagnostic protocol includes a physical exami- nation, CT neck and CT chest with IV contrast, and pan- endoscopy in the OR under general anesthesia (including laryngoscopy and esophagoscopy) with tonsillectomy and biopsies of suspicious mucosal areas. The CT/MRI detection rate for a primary tumor varies from 9% to 23%. The likelihood of discovering a primary tumor by an endoscopy and random biopsies is low. Without suspicious findings in clinical or radiologic exami- nations, a successful result can be obtained in 20%–29% of cases in some studies. When an endoscopic biopsy can be directed according to a suspicious clinical or radiologic finding, a detection rate of up to 60% has been reported. Ipsilateral tonsillectomy yields an 18%–44% rate in primary tumor. Some authors and institutions support bilateral tonsillectomy, because bilateral or contralateral tumors have been found in up to 10%–23% of cases.

Answer 118

The source of 90% of anterior nosebleeds is within Kiesselbach's plexus (also known as Little’s area) on the anterior nasal septum. There are five named vessels whose terminal branches supply the nasal cavity: 1) Anterior ethmoidal artery 2) Posterior ethmoidal artery 3) Sphenopalatine artery 4) Greater palatine artery 5) Superior labial artery The watershed area of these five vessels is in the anterior nasal septum, comprising Kiesselbach's plexus. This lies at the entrance to the nasal cavity and so is subject to extremes of heat and cold, and of high and low moisture, and is easily traumatized. The mucosa over the septum in this area is especially thin, making this the site of the majority of epistaxis.

Answer 119

1. (A) The anterior jugular vein can cross the midline overlying the proximal trachea. Midline cervical dissection without adequate visualization can injure the vein and require open surgical repair. The other veins do not cross the midline and are not generally at risk in tracheotomy.

Answer 120

2. (C) The cervical branch of the facial nerve innervates the lower lip through the marginal mandibular branch of the nerve (Fig. 3–7). As no cross innervation exits to other branches of the facial nerve, marginal mandibular branch injuries always yield paralysis of the same side of the lower lip. Injuries of the main trunk of the facial nerve or its temporal branch would usually produce upper facial paralysis as well.

Answer 121

3. (E) The phrenic nerve is the only component of the cervical plexus, which is not sacrificed during a radical neck dissection. It can be identified as superficial to the anterior scalene muscle (Fig. 3–8) with a nerve stimulator, although direct visualization is usually sufficient. Injury to the phrenic nerve can result in paralysis of the corresponding side of the diaphragm.

Answer 122

4. (E) Temporal artery inflammation causes severe throbbing unilateral temporal headache, lowgrade fever, visual changes, sweating, and malaise. Acute treatment with prednisone can be followed by temporal artery resection.

Answer 123

5. (C) Hypoxia can become the primary stimulation for respiration. Sudden elevation of PO2 can eliminate the respiratory drive, which will resume by lowering the PCO2 .

Answer 124

6. (E) Prolapse of mucosa overlying the true vocal cords (ventricle of Morgagni) can occur in people who routinely elevate air pressure in the chest and larynx. Treatment involves direct laryngoscopy and excision of the protruding mucosa. The other choices, although less likely, must also be considered.

Answer 125

7. (D) Spasmodic dysphonia often occurs in both men and women over 40-years old who strain their voices. Fluctuation with normal speech can occur, unlike the other choices presented. The vocal cords appear normal on routine laryngeal exam. Temporary improvement using botulinum toxin is reported.

Answer 126

8. (A) Compression of the recurrent laryngeal nerve due to compression of the cricothyroid joint can occur subsequent to choking injury of the neck. Although fracture and internal bleeding can also occur, these are less likely. Acute onset dyspnea secondary to laryngeal tumor is unlikely.

Answer 127

9. (C) Dysphagia and aspiration can result from disruption of the internal branch of the superior laryngeal nerve, resulting in sensory loss of the larynx. Contralateral superior laryngeal nerve compensation usually corrects these symptoms.

Answer 128

10. (C) Unilateral nasal discharge in a young child is often due to foreign body in the nose. Although the other choices should also be considered in the differential diagnoses of rhinorrhea, nasal foreign body in the child is most likely.

Answer 129

11. (E) Papillary cystadenoma lymphomatosum is also called Warthin’s tumor. It occurs mainly in men. The epithelial component is interspersed with lymphoid tissue that shows germinal centers. The most common tumor of the parotid gland is a pleomorphic adenoma, with papillary cystadenoma (although much less frequent) as the second most common tumor. Mikulicz’s disease involves chronic inflammation and swelling of the salivary glands, which is benign and usually painless.

Answer 130

12. (B) The most common cause of primary mediastinal tumor is a neurogenic tumor (20–25%), and 10% are malignant (more likely in children). They usually arise from an intercostal nerve or sympathetic ganglion. Varieties of neurogenic tumors include neurilemmoma (schwannoma), neurofibroma, ganglioneuroma, and neuroblastoma. Next in frequency (of primary mediastinal tumors) are thymoma, congenital cysts, and lymphoma. New diagnostic techniques have resulted in detection of larger numbers of these lesions.

Answer 131

13. (C) Spinal anesthesia induces venous vasodilation because of sympathetic blockade. Venous pooling can seriously impair venous return. It is the sympathetic blockade and not somatic nerve blockade that is responsible for the vasomotor and respiratory changes. It is important to ensure that volume depletion is corrected before spinal anesthesia, because venous return and hence cardiac output are diminished. These changes are aggravated by keeping the head up.

Answer 132

14. (D) The role of thymectomy in treating patients with myasthenia gravis who have a thymoma is well established. The thymus gland is located in the anterior mediastinum and can be approached by a cervical or mediastinal approach. It arises from the third and fourth branchial arches. Thymectomy is frequently advised for patients with myasthenia gravis who do not have a thymoma; however, there are some authorities who would treat these patients initially with an anticholinesterase drug such as pyridostigmine (Mestinon). Corticosteroid therapy may be indicated when thymectomy has failed, but it must be undertaken cautiously, because the drug may precipitate severe weakness. Pneumococcal infections (which may occur after splenectomy performed in children) are not a specific complication noted after thymectomy.

Answer 133

15. (C) Bronchogenic carcinoma accounts for 70–80% of all cases of superior vena cava (SVC) obstruction; primary mediastinal tumors are the second most common cause. The main bronchial lymphatics are located at the tracheal bifurcation and immediately to the right and left of the trachea. Tuberculosis and mycotic infections are the most likely causes of chronic fibrosing mediastinitis.

Answer 134

16. (D) CT is useful, because it delineates the calcification and shows the pattern of the calcification. There is no need for intervention at this stage, because most lesions of this nature are probably benign granulomas.

Answer 135

17. (D) By definition, a solitary nodule is one that is 5 cm or less in diameter. In most series, 60% of such lesions are benign, and 40% are malignant. The presence of irregular margins, the absence of calcification, a recent onset of symptoms, or an increase in size of the lesion within a relatively short period (several months) indicate the greater likelihood of malignancy. Thin-section CT scanning may add further information.

Answer 136

18. (A) Bronchoscopy is the initial step, particularly if the patient is a smoker and a good risk for surgery. If cancer is confirmed, thoracotomy will probably be undertaken. Patient age is an important consideration in the management of a solitary pulmonary nodule; malignancy occurs in less than 1% of patients under 35 years of age. Benign lesions, such as bronchopulmonary sequestration, which usually affects the posterior aspect of the inferior lobes of the lung, must be considered. Bronchopulmonary sequestration is usually asymptomatic, unless complications occur.

Answer 137

19. (E) In apical lung cancers, the malignant tumor may extend above the thoracic inlet, penetrate the suprapleural membrane, and infiltrate the structures found at the root of the neck. The first thoracic nerve and lower trunk of the brachial plexus are most likely to be involved initially, as T1 passes along the inner border of the first rib to reach the neck. If the sympathetic nerve is involved, pupil constriction and ptosis may be evident (Horner syndrome). The other listed items are all features of the paraneoplastic syndrome associated with lung cancer and do not necessarily indicate extranodal metastasis. Cushing’s syndrome in lung cancer occurs more frequently in men and in an older age group and has a more rapid downhill course than typical Cushing’s syndrome. SIADH should be suspected if the patient with a lung lesion develops unexplained mental changes and an extremely low serum sodium level. Fluid restriction is required. Urine osmolarity is low.

Answer 138

20. (A) Hypercalcemia is attributed to the secretion of parahormone from a localized squamous cell carcinoma (paraneoplastic effect); as such, improvement may be seen after surgical resection. Following extension of the tumor into the chest wall, radiotherapy and subsequent extensive resection carried out in selected cases may occasionally be indicated. Small-cell carcinoma (also known as oat-cell carcinoma) accounts for 20–25% of cases of bronchogenic carcinoma, arises centrally and tends to metastasize widely. The initial treatment is combination chemotherapy followed by radiotherapy in those whose cancer responds.

Answer 139

21. (B) Uncorrected hypercarbia is the major contraindication to total pneumonectomy. Surgery is the treatment of choice for nonsmall-cell carcinoma of the lung. Although 25% of patients with bronchogenic carcinoma may undergo thoracotomy, many of these patients will have unresectable lesions. Patients with a FEV1 less than 2 L, a FVC under 70% of predicted value, and maximal voluntary ventilation (MVV) under 50% are likely to tolerate operation poorly. The normal FEV1 /FVC ratio is 0.7 or less; in severe obstructive dysfunction, it is under 0.45. Total atelectasis of the lung may be associated with obstruction of the main bronchus by the tumor.

Answer 140

22. (D) Patients with small-cell carcinoma should not be treated initially by thoracotomy. This cancer responds favorably to combination chemotherapy, but few patients survive for more than 1 year. More than 160,000 cases of bronchogenic carcinoma are diagnosed in the United States per year. It accounts for 33% of all cancer deaths in men and 20% of all cancer deaths in women. The most common cancers of the lung are squamous carcinoma, 30% (tumor tends to be central); adenocarcinoma, 30%, (tumor tends to be peripheral) small-cell carcinoma, 20% (tumor tends to be central); and large-cell carcinoma, 15% (tumor tends to be peripheral).

Answer 141

23. (A) The arch of the aorta is above the arbitrary line drawn between the manubriosternal joint (angle of Louis) and the lower border of the fourth thoracic vertebra level. Therefore, it is located entirely in the superior mediastinum behind the manubrium. The projected line passing behind the manubriosternal junction and the lower border of T4 is a key surgical anatomic landmark of this region. The ascending aorta (anteriorly), descending aorta (posteriorly), and pulmonary trunk are below this level. The left recurrent laryngeal nerve curves around the ligamentum arteriosus, the arch of the azygous vein enters the SVC, and the upper third of the esophagus are separated arbitrarily from the middle third at this level. On a plain film of the chest, the tracheal bifurcation (carina) is a useful marker of this line.

Answer 142

24. (C) Although there is a history of previous thyroid cancer, the presence of a solitary nodule on chest x-ray is more likely to represent a primary carcinoma of the lung than a solitary secondary metastasis. In metastasis, the lesions are more often multiple, they frequently appear bilaterally, and they more commonly present in the lower area of the lungs. A CT scan would be helpful in delineating the pulmonary findings.

Answer 143

25. (C) The most likely diagnosis, malignant epithelioma, commonly occurs following chronic exposure (>20–40 years) to asbestos. We need to consider this diagnosis in those employed in milling and construction, as well as in workers in pipe, textiles, gaskets, and other industries in which asbestos (especially crocidolite form) is used. In 75%, the diffuse (malignant) form occurs; less than 25% will survive more than 1 year after the diagnosis is established. In advanced disease, lesions below the diaphragm are frequently encountered.

Answer 144

26. (C) Cystic fibrosis is the most common cause of chronic obstructive lung disease (COLD) in children and adolescents. It is an autosomal-recessive disease that affects widespread exocrine glands. COLD is evident in all patients who survive childhood.

Answer 145

27. (A) Ipratropium bromide bronchodilator therapy will frequently improve pulmonary function in patients with COPD. Two to four inhalations every 4–6 hours are prescribed. COPD is due to emphysema (COPD type A) or chronic bronchitis (COPD type B). In the early stages, small airway dysfunction (abnormal closing volume) is found. As the disease proceeds, the FEV1 is reduced, then the FEV1 /FVC ratio (<0.7).

Answer 146

28. (C) The presence of multiple masses on a chest x-ray should alert the physician to the possible diagnosis of pulmonary AV fistula. Needle biopsy and endobronchial biopsy of the lesion should not be attempted, because severe hemorrhage may be precipitated. Paradoxical emboli, brain abscess, and hemothorax are recognized complications. If the fistula is localized, resection is undertaken; in multiple lesions, therapeutic embolization is done. In addition to AV malformation, multiple masses on a chest xray could be due to metastasis, granulomatous infection, or sarcoid or rheumatoid arthritis.

Answer 147

29. (D) In mediastinal tamponade, hypotension, dyspnea, cyanosis, and a decrease in pulse pressure will be evident. During inspiration, the pulse pressure is further impeded to cause obstruction to transmitted ACV waves in the neck; in congestive cardiac failure, the ACV waves recorded in the neck are more prominent. Paresis of the arm is unlikely to occur, because the lower part of the brachial plexus (T1) passes along the inner border of the first rib to reach the neck.

Answer 148

30. (B) Mediastinal hemorrhage after trauma may result from blunt or penetrating injuries. Tamponade should be suspected if hypotension, cyanosis, dyspnea, and venous congestion occur.

Answer 149

31. (B) Dissecting thoracic aneurysm should be suspected in Marfan’s syndrome, pregnancy, bicuspid aortic valves, and coarctation. The onset of pain is sudden and severe and radiates to the back. Pulse discrepancy is frequently seen. The hypertension should be treated initially before any surgery is contemplated. The mortality rate of immediate (within 24 hours) surgical resection of the ascending aorta (type A) is 20%; however, if surgery is delayed, the mortality is 50% at 2 weeks and 90% at 3 months.

Answer 150

32. (E) The eleventh and twelfth ribs are free anteriorly and like other ribs articulate with costal cartilage anteriorly. However, the anterior margins of these ribs are free (float) and do not form part of the costal margins. The pleural reflection posteriorly intersects the twelfth rib. Ribs that articulate with the sternum are called true (ribs 1–6 or 7); the remainder are called false ribs.

Answer 151

33. (D) In ARDS, poor alveolar gas exchange and interstitial edema are evident in the presence of normal or lowered PCWP. The changes are caused by damage to capillary and alveolar epithelial cells consequent to the release of proinflammatory cytokines, which, in turn, arise from stimulated lymphocytes and macrophages. Other clinical features suggestive of ARDS are diffuse (“fluffy”) pulmonary infiltrates and refractory hypoxemia (PaO2 /FiO2 <200).

Answer 152

34. (C) ARDS is caused by pulmonary or systemic insult. It is characterized by bilateral pulmonary infiltrates, hypoxemia, noncompliant lungs, and a normal or low PCWP, and steroids have no proved value in the management of ARDS, and their use may be deleterious in the presence of sepsis. PEEP, if required, should be used cautiously with the lowest FiO2 that maintains the PO2 above 60 mm Hg. Excessive fluid overload should be avoided. Ventilation should be with lower tidal volumes and decreasing peak airway pressures. Management strategies in ARDS are aimed largely at supportive care, maintaining tissue oxygenation and preventing further lung injury secondary to mechanical ventilation. Smaller tidal volumes are used (5–7 mL/kg) to prevent volutrauma as well as to decrease the peak inspiratory pressures.

Answer 153

35. (E) Culture for mycobacterium usually requires 6 weeks before a diagnosis can be made. The clinical and x-ray features are suggestive of tuberculosis. The sedimentation rate is increased in the presence of active disease. The incidence of tuberculosis in the United States has increased in recent years. In many cases of primary infection, resolution occurs without symptoms. The pulmonary focus remains dormant (Ghon) and may become activated, causing caseation of the lung, formation of a thick-walled fibrous cavity, tuberculous bronchitis, bronchiectasis, hemoptysis, and cavitation. Sputum examined for acid-fast bacilli may be inadequate, because saprophytic organisms may be detected. The Kveim test is used in the differential diagnosis to exclude sarcoid.

Answer 154

36. (D) In the early stages of HIV infection, skin testing for tuberculin is intact; however, falsepositive results occur because of infection by nontuberculous mycobacteria and are common because of the immune disorder. Most patients with tuberculosis, who are compliant, can be treated on an outpatient basis.

Answer 155

37. (B) Bronchiectasis is caused by a congenital or acquired dilation of the segmental, subsegmental, or branches of the bronchi. Patients with B lymphocyte disorders are more likely to develop lower respiratory tract infection and bronchiectasis than those with impaired T-cell immunity. Treatment is aimed at obtaining maximal drainage. Resection may be indicated when the disease is localized and persistent symptoms and complications occur.

Answer 156

38. (A) Cystic fibrosis is an autosomal-recessive disorder of the exocrine glands and occurs in neonates who survive an episode of intestinal obstruction due to mucoviscidosis. Cystic fibrosis accounts for more than one-half of the cases of bronchiectasis seen today. Other causes include acute and chronic lung infections, humoral immunodeficiency, and localized bronchial obstruction (e.g., carcinoma). The basal segments of the lung, lingula, and right middle lobes are involved most frequently.

Answer 157

39. (C) Bronchogenic cysts are located in the mediastinum but are seen most frequently behind the carina. They have a thin wall, are lined by bronchial epithelium, and contain mucus. Bronchogenic cysts are usually asymptomatic, but symptoms may occur because of compression, with cough, wheezing, and possibly dysphagia. Bronchogenic cysts may become infected and rupture into surrounding organs. Cysts constitute 20% of mediastinal mass lesions. The most common mediastinal cyst is the pericardial cyst, which is found most often at the right costophrenic angle.

Answer 158

40. (D) Bronchopulmonary sequestration can be differentiated from a bronchogenic cyst; in that it is composed of nonfunctioning lung tissue that is disconnected from the remaining lung; it has a separate blood supply. Glomus tumors are rare tumors that arise in the middle ear or jugular bulb. Patients complain of tinnitus and hearing loss.

Answer 159

41. (D) There are three major openings of structures that penetrate the diaphragm at differing thoracic vertebra levels. The IVC enters at T8 (to the right of the midline), the esophagus at T10 (to the left of the midline), and the aorta at T12 in the midline.

Answer 160

42. (A) Funnel chest (Fig. 3–9) is the most important congenital chest wall deformity. It is usually present at birth, and there is marked asymmetry. The heart is displaced to the left. There is often a familial history, and associated congenital heart disease may frequently be encountered. Correction is recommended in asymptomatic patients with prominent deformity to avoid permanent cardiopulmonary changes. In flail chest, paradoxical respiration occurs as the chest wall deformity is sucked inward during inspiration. It occurs after extensive rib trauma where individual ribs are separated in two different sites.

Answer 161

43. (A) Any object that compromises the blood supply to the tracheal mucosa or cartilage can cause stenosis. When the mean intramural pressure exceeds 20–30 mm Hg, damage may be anticipated. Riedel struma is a rare fibrosing thyroid condition, which must be differentiated from carcinoma and may cause severe tracheal stenosis. Achalasia is a neuromuscular defect at the lower end of the esophagus causing dysphagia, because of nonmechanical esophageal obstruction.

Answer 162

44. (A) On the left side, the pleural reflection deviates to the left, anteriorly between the fourth and sixth costal cartilages, to accommodate the cardiac notch. Although the right and left pleural reflections approach each other in the midline, there is no direct communication between the two sides.

Answer 163

45. (D) Frequently, a fracture cannot be seen on the chest x-ray; however, the patient should be treated for fracture, although none is seen on the x-ray. Pneumothorax may occur if more than one rib is involved, but a chest tube is indicated only if it is of substantial size or increasing in amount. Hemothorax usually occurs because of a tear in the intercostal or other intrathoracic vessels.

Answer 164

46. (D) A thoracoabdominal incision is still used occasionally where access to both the upper abdomen and posterior thoracic structures is required. The main reasons for less frequent use of this incision are poor healing of the divided costal margin, postoperative pain, and an increased risk of infection in both the thoracic and abdominal compartments.

Answer 165

47. (B) Sternal injuries usually involve the body or manubriosternal junction in a transverse direction and frequently cause displacement. Sternal injuries occur most commonly as a result of injury by steering wheel impact in car accidents. It is important to exclude cardiac and major vessel injury in such injuries.

Answer 166

48. (B) Most lesions of the trachea, except infiltrating adenoid cystic carcinoma, that cause tracheal stenosis should be resected when possible. In general, up to 50% of the trachea may be resected. Unequivocal postintubation stenosis is treated by surgical repair. Congenital tracheal stenosis should be treated by surgery if symptoms necessitate it. Dilatation can result in rupture of the trachea.

Answer 167

49. (B) Patients with hyperparathyroidism develop demineralization, and 1.5% shows osteitis fibrosa cystica. The presence of subperiosteal resorption of bone of the phalanges and lamina dura of the teeth are fairly diagnostic radiological findings of hyperparathyroidism. Chondromas account for 20% of benign tumors of the rib and occur at the costochondral junction. Osteochondromas arise from the cortex and usually occur in men. Eosinophilic granuloma results in a destructive lesion apparent on x-ray.

Answer 168

50. (D) Antibiotics and vigorous attempts to obtain bronchial drainage will treat the abscess adequately in the majority of cases. Lung abscesses commonly are associated with aspiration pneumonia, where the abscess is found posteriorly. In the presence of an unexplained lung abscess, bronchoscopy is essential to exclude a foreign body or tumor that could cause bronchial obstruction.

Answer 169

51. (B) Branchial cleft cysts (Fig. 3–9) arise from the second and third branchial clefts. Branchial cysts may become evident after an URTI and present as a mass anterior to the sternocleidomastoid muscle. Intraoperatively, they can be traced to pass between the and external carotid artery to the piriform sinus or tonsillar fossa.

Answer 170

52. (C) Cystic hygromas are relatively rare tumors. Most are encountered in the posterior triangle of the neck, but occasionally they are found in the mediastinum, axilla, or groin. They are often noted at birth and represent persistence of primary lymphatic buds. They extend into the surrounding tissues but are not associated with malignancy. Transillumination is a useful sign to diagnose this lesion.

Answer 171

53. (D) Females are affected by myasthenia gravis twice as commonly as males. It is an autoimmune disease that produces antibodies to acetylcholine receptors. The external ocular and other cranial muscles are often involved at an early stage. There is a deficiency in acetylcholine receptors, and thymectomy is often helpful.

Answer 172

54. (D) Squamous carcinoma of the lip comprises 15–20% of all malignant tumors of the oral cavity. In approximately 30%, there is a clear association with heavy exposure to the sun. The incidence increases in those areas where there is more southerly latitude, the air is dry, and the altitude is higher.

Answer 173

55. (C) If the lesion is treated early, patients will achieve a cure in most cases. The upper lip is involved in 10% of patients.

Answer 174

56. (C) Hyperkeratosis of the lip is a premalignant lesion and usually occurs in people exposed excessively to the sun. The mucosa undergoes metaplasia to keratosquamous epithelium. The lip becomes pale, thin, and fragile, with cracks and fissures, and is covered with a white base.

Answer 175

57. (D) Ameloblastoma is a benign tumor and usually occurs at the junction of the body and ramus of the mandible. Although it is a benign tumor, it recurs if inadequately excised. It is relatively radioresistant. Histologically, odontogenic epithelium is seen in connective tissue stroma with extensive areas of cystic degeneration.

Answer 176

58. (B) The lingual nerve swings forward deep to the mylohyoid muscle and crosses twice over the submandibular (Wharton’s) duct. The mandibular branch of the facial nerve (not listed in the answer choices) may accidentally be injured below the angle of the mandible (Fig. 3–10). Injury to this branch causes serious facial deformity.

Answer 177

59. (C) Squamous cell carcinoma of the tongue frequently (40–60%) metastasizes to the lymph glands. Carcinoma of the tongue usually commences at the tip or side. The 5-year survival rate for carcinoma of the tongue is 40%, but it improves to 55% if lymph nodes are not involved.

Answer 178

60. (B) Carcinoma of the posterior third of the tongue is often detected late and carries a worse prognosis. Posterior-third tongue tumors are also called lymphoepitheliomas. These lesions can be poorly differentiated.

Answer 179

61. (A) Tumors of the hard palate usually arise from the minor salivary glands. Cancers of the lip, tongue, esophagus, and larynx are often squamous cell carcinoma.

Answer 180

62. (A) Poorly differentiated squamous cell carcinoma of the floor of the mouth tends to be more invasive than better-differentiated tumors. Poorer prognosis can be expected when invasion is larger than 9 mm, perineural invasion is noted, and lymph node metastasis is evident.

Answer 181

63. (C) Nasopharyngeal carcinoma is prevalent in China. It has been associated with high levels of Epstein-Barr virus titers. The most common sign is a neck mass, even when the primary lesion is microscopic. The first cranial nerve to be affected is the abducent (VI) and indicates cranial extension.

Answer 182

64. (A) Any object that compromises the blood supply to the tracheal mucosa or cartilage can cause stenosis. When the mean intramural pressure exceeds 20–30 mm Hg over a prolonged period, damage occurs.

Answer 183

65. (A) Verrucous carcinoma is a low-grade malignancy and is seen more frequently in the southern part of the United States. It is found most commonly on the gingival-buccal junction in tobacco chewers. It is grayish white and exophytic. Radiation is associated with possible metastases. If not excised, the lesion tends to invade locally.

Answer 184

66. (D) Juvenile nasopharyngeal hemangiofibromas are rare nonmalignant tumors containing both fibrous and vascular tissue. They occur exclusively among boys.

Answer 185

67. (C) If the neck nodes are removed, some patients have surgically curable primary disease. In some series, as many as 20% remain free of disease for more than 5 years without any manifestation of a primary tumor. It is essential to search extensively for a primary source before labeling the lesion as a possible branchial cleft carcinoma, which is extremely rare.

Answer 186

68. (D) More than 80% of neck gland tumors arise from structures above the clavicle. The piriform fossa is lateral to the aryepiglottic folds and is a major site where a primary cancer may remain hidden from early detection. Twenty percent of neck gland tumors are primary and 80% represent metastatic disease.

Answer 187

69. (D) The response is transient, lasting only 2–3 months. The results of this type of therapy, combined with those of artery occlusion, radiotherapy, or other modes of chemotherapy, require further evaluation.

Answer 188

70. (B) The classic block dissection includes sternocleidomastoid muscle, the external and internal jugular veins, the spinal accessory nerve, the submandibular gland, and the lymphatic tissue of the lateral compartment of the neck. Procedures that preserve muscle, nerve, or vessels are called modified neck dissection.

Answer 189

71. (B) The chorda tympani (branch of the facial nerve) join the lingual nerve in the infratemporal fossa to supply the anterior two-thirds of the tongue with taste fibers (cell stations in the geniculate ganglion of the facial nerve). It also contains the secretory parasympathetic fibers to the submandibular and sublingual glands.

Answer 190

72. (D) The thymus gland is removed in certain cases of myasthenia gravis. It is located in the anterior mediastinum and can be approached by a cervical or mediastinal approach. It arises from the third and fourth branchial arches. Pneumococcal infections are particularly likely to develop after splenectomy performed in children.

Answer 191

73. (A) The most common organisms isolated in acute pharyngitis are streptococci, virus, Neisseria gonorrhoeae, and mycoplasma.

Answer 192

74. (C) Odynophagia is a sensation of sharp retrosternal pain on swallowing. It is usually caused by severe erosive conditions such as Candida, herpes virus, and corrosive injury following caustic ingestion.

Answer 193

75. (B) The most common source of epistaxis is Kisselbach’s vascular plexus on the anterior nasal septum. Predisposing factors include foreign bodies, forceful nose-blowing, nosepicking, rhinitis, and deviated septum.

Answer 194

76. (D) Carotid body tumor is the most common type of paraganglioma in the head and neck region, followed by the glomus jugular tumor. Carotid body tumor grows slowly, rarely metastasizes, and may secrete catecholamines. The tumor usually is supplied by the external carotid artery, and dissection to remove it off the carotid bifurcation may be difficult and cause bleeding. Malignancy occurs in 6% of patients.

Answer 195

77. (E) Bell’s palsy (of the facial nerve) has been attributed to an inflammatory condition of the facial nerve at the site where it exits through the stylomastoid foramen. Its cause remains unclear, and recent studies indicate a possible association with reactivation of herpes simplex virus in some cases. Facial paresis usually comes on abruptly

Answer 196

78. (B) Prospective nonrandomized evaluations of treatment duration of acute otitis media reveal no difference in outcome if given over 5-day, 7-day, or 10-day duration. However, 10-day treatment is indicated for children with history of acute otitis media within the preceding month.

Answer 197

79. (A) Neuroleptic anesthesia is the use of agents that suppress psychomotor activity. Droperidol produces marked sedation and tranquilization. The onset of action is 3–10 minutes after injection, but the full effect may not be noted until 30 minutes after injection. The sedative action lasts 2–4 hours. It potentiates the action of central nervous system (CNS)-depressant drugs, can cause hypotension, and causes mild aadrenergic blockade.

Answer 198

80. (C) The most common complication of thyroid and parathyroid surgery is iatrogenic injury to the recurrent laryngeal nerve, which can result in temporary (up to 7.1%) or permanent (up to 3.6%) paralysis of the vocal cord.

Answer 199

81. (B) Laryngomalacia is characterized by inspiratory stridor and is caused by redundant epiglottis and aryepiglottic folds in young children. The condition usually resolves without surgical intervention.

Answer 200

82. (B) Jet irrigation (e.g., Water Pik) should be avoided to remove cerumen impaction. Detergent ear drops (such as 3% hydrogen peroxide) may be used. Aqueous irrigation should be avoided if organic material is present, because further swelling will be induced.

Answer 201

83. (A) The presence of a nasogastric tube causes swelling and irritation of the nasal mucosa. This, in turn, may partly occlude drainage of the sinus into the meatus.

Answer 202

84. (B) Foreign bodies in the ear canal are more frequently encountered in children than adults. In general, foreign bodies in the ear are removed under microscopic control to avoid further injury.

Answer 203

85. (D) Rapid testing for streptococci with latex agglutination (LA) antigen test is much less sensitive than with solid-phase enzyme-linked immunoassay (ELISA).

Answer 204

86. (B) Pharyngeal (branchial arch) remnants account for many cysts or fistulas in the lateral neck. The associated tract can be found in various locations. Thyroglossal duct cysts associated with the decent of the thyroid gland are usually midline, extending as high as the base of tongue.

Answer 205

87. (A) Epistaxis in children and young adults usually arises from the anterior nasal septum (Kiesselbach’s plexus). In elderly persons, however, spontaneous rupture of a sclerotic blood vessel in the posterior nasal septum is usually the cause of bleeding, especially in combination with hypertension.

Answer 206

88. (A) Tinnitus is the perception of abnormal noise in the ear or head. It is usually attributed to a sensory loss; pulsatile tinnitus occurs with conductive hearing loss and is due to carotid pulsations becoming more apparent.

Answer 207

89. (E) Surgical drainage of otitis media (myringotomy) is performed in either chronic infections or severe infections. Complications of otitis media include mastoiditis and meningitis.

Answer 208

90. (E) These may be difficult to excise because of the focal nerve involvement by the hemangioma.

Answer 209

91. (D) Blowout fractures of the orbit exhibit epistaxis; subcutaneous emphysema and periorbital ecchymosis are also frequently encountered. Treatment of most severe injuries is by surgical repair, often by a lower lid blepharoplasty incision. Enopthalmous, lateral diplopia and blindness do not generally occur.

Answer 210

92. (E) Tympanostomy tube placement is performed through the external auditory canal with microscopic guidance. The tympanic membrane is directly visualized after clearing wax and debris from external auditory canal. Otorrhea is the most common sequela, requiring tube removal in 13.5% of long-term tubes and 0.9% of short-term tubes.

Answer 211

93. (C) The external laryngeal nerve supplies the cricothyroid muscle, which assists in tensing the cords.

Answer 212

94. (A) Scrofula is tuberculosis lymphadenitis. It may occur in immunocompromised hosts as well as in patients from underdeveloped countries. A chest x-ray must be obtained and a purified protein derivative (PPD) skin test must be carried out. The response rate to antituberculous drugs is good, but excision of the residual lesion may be required.

Answer 213

95. (D) Mucor is an opportunistic mold that causes mucormycosis. At least 50% of reported cases are associated with uncontrolled diabetes, and many of the remaining patients are immunosuppressed. It appears as black crusting in the nose and sinuses and spreads rapidly to involve the cerebrum. Biopsy reveals nonseptate hyphae, which confirms the diagnosis. Treatment is directed toward control for diabetic ketoacidosis and use of amphotericin B.

Answer 214

96. (B) Dermoid cysts arise along line of fusion of embryonic parts. In the floor of the mouth, the swelling forces the tongue upward. Alternatively, the swelling may occur below the mylohyoid muscle, where it gives the impression of a double chin. It is not a premalignant lesion. It has an epithelial lining and may contain secretions, sloughed-off cells, and hair.

Answer 215

97. (D) In Peutz-Jegher syndrome, pigmented melanin spots are found in the buccal and perineal region. The lesions are flat and greenish black in the buccal region and remain after puberty. Pigmentation is found inside the mouth, nostrils, palms, and feet. Usually at about 20–30 years of age, hamartomatous polyps are found in the small intestine, but other parts of the alimentary tract may also be involved. Adenocarcinoma develops in 23% of patients.

Answer 216

98. (D) Benign mixed tumor (pleomorphic adenoma) requires appropriate excision (superficial parotidectomy). If the tumor is shelled out, recurrence is likely. Approximately 80% of tumors of the salivary glands occur in the parotid gland.

Answer 217

99. (B) The trigeminal nerve exits from the foramen ovale to enter the infratemporal fossa. The motor mandibular division of cranial nerve V also exits through the same opening.

Answer 218

100. (A) If the thyroid gland is absent from the neck, it may be in the lingual position at the foramen cecum. Excision of this lesion from the tongue will require thyroid hormone replacement.

Answer 219

101. (B) Nasopharyngeal cancer is most closely associated with Epstein-Barr virus. This virus is also associated with infective mononucleosis and Burkitt’s lymphoma.

Answer 220

102. (E) If the tumor should extend upward into the sphenoid bone, the cavernous sinus may be involved.

Answer 221

103. (B) The tip of the tongue drains into the submental lymph nodes, whereas, the side of the tongue drains into the submandibular lymph nodes.

Answer 222

104. (G) Dermoid cysts form along lines of fusion of embryological dermatomes of the skin. In the neck, they are commonly above the thyroid cartilage and may be classified as one of four varieties, central or lateral in the midline and above or below the mylohyoid muscle.

Answer 223

105. (G) The thyroid develops from the foramen cecum in the tongue and descends to its definitive position in the neck. Failure of the tract to close may result in a thyroglossal duct cyst.

Answer 224

106. (A) An elevated ionic calcium and elevated blood levels of intact PTH clinches the diagnosis of hyperparathyroid. Primary hyperparathyroidism can result in bone demineralization and renal calculi if neglected. Hyperparathyroidism may be manifestation of the multiple endocrine neoplasia syndrome. Pancreatic islet cell tumors, vi2 gastinomas and insulinomas, and pituitary tumors are part of the multiple endocrine neoplasia MEAN 1 syndrome. Myoglobin in the urine is present in patients with rhabodmyolysis and is not associated with elevated serum calcium, and is after associated with hyperkalemia.

Answer 225

107. (B) An ectopic thyroid gland can be located anywhere from the base of the tongue to the mediastinum. It often results in the failure of descent resulting in either a linginal thyroid or ectopic thyroid in the midline of the neck. The so called lateral aberrant thyroid is usually a metastasis from papillary carcinoma of the thyroid. Angioneurotic edema is an acute allergic reaction, which causes a sudden swelling of the whole tongue with airway obstruction.

Answer 226

108. (E) Hyperthyroidism could be diffuse primary hyperthyroidisms, Graves’ disease, or a toxic nodular goiter. Graves’ disease is an autoimmune hyperthyroidism. The treatment consists of medical management with use of antithyroid drugs such as methimazole, or ablation of the gland with radioactive I131, or surgically with subtotal thyroidectomy. Failure of medical management requires oblation procedures either with I131 or surgery. Lugols iodine is used in preparation to surgery. Steroids are not used in the treatment of hyperthyroidism. It may be used in the management of thyroid storm, a life threatening condition.

Answer 227

109. (B) Definitive treatment of hyperparathyroidism is parathyroidectomy. When serum calcium is above 14 mgm/dL the patient is in hypercalcemic crisis. Immediate treatment of this condition requires hydration with normal saline and use of diuretics to bring down the serum calcium level. A positive parathyroid scan will help to locate an adenoma of the parathyroid preoperatively.