craniomaxillofacial Flashcards
A 45-year-old man comes to the emergency department because of new-onset left-sided facial weakness. Two days ago, the patient fell on the left side of his head. He sustained a 3-cm laceration of the left medial cheek near the nose that was repaired. After repair of the laceration, he had full facial (VII) nerve function. On examination today, the patient has normal facial symmetry at rest. When he is asked to animate, there is diminished function of all branches of the left facial nerve. CT scan of the head shows a transverse fracture of the petrous portion of the left temporal bone. Which of the following is the most appropriate next step in management?
A) Administration of high-dose corticosteroids and observation
B) Cross-facial nerve grafting using the sural nerve
C) Decompression of the facial nerve through a transmastoid approach
D) Immediate facial nerve exploration through the repaired laceration
E) Initiation of a 2- to 4-week course of ceftriaxone and observation
A. steroids and observation
The facial nerve injury is likely proximal due to symptoms of all thirds of the face and therefore associated with the temporal bone fracture. The medial cheek laceration is unlikely to be related, and exploration would risk further injury. The facial nerve travels through the petrous portion of the temporal bone before exiting the stylomastoid foramen and can be affected in 7 to 10% of temporal bone fractures
A 6-year-old boy with right congenital corneal anesthesia and a history of multiple corneal abrasions and ulcerations is scheduled to undergo donor sural nerve grafting. Which of the following graft targets is most likely to provide the greatest improvement in corneal sensation?
A) Left supraorbital nerve to right corneal nerve
B) Left supraorbital nerve to right supraorbital nerve
C) Left supratrochlear nerve to right scleral limbus
D) Right frontal branch of facial (VII) nerve to right supratrochlear nerve
E) Right infraorbital nerve to right corneal nerve
C left supratrochlear to right scleral limbs
The ipsilateral, supraorbital, and supratrochlear nerves provide sensation to the cornea. There are many causes for insensate cornea, including congenital and acquired conditions. Herpes infection is one of the leading causes.
Which of the following factors is most predictive of a successful outcome when neonatal ear molding is used to correct congenital ear abnormalities?
A) Breastfeeding status of the mother
B) Duration of therapy
C) Hearing status
D) Type of ear anomaly
D. type of ear anomaly
Deformations such as Stahl ear deformity and lop ear deformity have high treatment success rates, and deformations such as constricted ear deformity have much lower success rates.
A 10-month-old male infant undergoes bilateral cleft palate repair using the two- flap palatoplasty with Z-plasty technique. His parents have expressed a goal of only having one palate surgery. The cleft is very wide, but the plastic surgeon achieves a satisfactory tension-free nasal lining repair. The oral closure is tenuous in the area of the hard-soft palate junction overlying the nasal lining transition. Which of the following is the most appropriate next step to achieve tension-free, watertight oral lining closure?
A) Fracture the hamulus
B) Mobilize and divide the greater palatine artery
C) Use a buccal myomucosal flap
D) Use a posterior pharyngeal flap
E) Use a tongue flap
C. buccal myomucosal flap
Mobilization of the periosteal flaps, freeing of the greater palatine artery, and relaxing incisions all aid in advancing the flaps medially for a tension-free oral closure after a tension-free nasal lining closure.
The buccal myomucosal flap has increased in popularity for the purpose of fortifying the hard-soft junction, for fistula closure, and for palatal lengthening.
P flap: good for lengthening, not appropriate at this age and primary repair
tongue flap: can’t bottle feed, used in older kids, 2 stages
fracture of hamulus: doesn’t add mobilization
divide greater palatine: supply for flap so it would die
A 6-year-old boy is brought to the emergency department with pain and malocclusion 1 hour after an unwitnessed fall from his bicycle. Physical examination shows a 1.5-cm laceration in the submental region and a deviation of the chin to the right with a left-sided posterior open bite. Which of the following is the most likely fracture pattern in this patient?
A) Bilateral condylar head fractures
B) Left angle fracture and symphyseal fracture
C) Left condylar neck fracture and right body fracture
D) Right condylar neck fracture and left parasymphyseal fracture
D. right condylar neck and left parasymphyseal
A right-sided condylar neck fracture will result in loss of height of the right ramus and premature contact of the right dentition. A right-sided crossbite and a left posterior open bite are also noted in this scenario.
A 25-year-old Asian man comes to the office for consultation regarding angle of jaw fullness. The patient reports no history of temporomandibular joint conditions, dental disease, or bruxism. Injection of 30 units of botulinum toxin type A is administered. On follow-up examination 3 weeks later, the patient reports an asymmetric smile. Unintentional diffusion of botulinum toxin into which of the following structures is most likely responsible for the asymmetry?
A) Masseter muscle
B) Orbicularis oris muscle
C) Parotid gland
D) Risorius muscle
E) Temporalis muscle
D. risorius muscle
risorius muscle attaches to the anterior or middle part of the masseter muscle in greater than 95% of individuals and is thought to be the most likely cause due to its variability in location, and thus more challenging to prevent. Of the options listed, it is the best anatomic choice. A parotid diffusion is more likely to result in xerostomia, not facial asymmetry. Temporalis paralysis would result in weakened bite, not facial asymmetry. Orbicularis oris weakness would result in diminished pursing of the lips.
Compared with adults, management of isolated condylar fractures in children in primary dentition is most likely to require which of the following?
A) Condylectomy
B) Nonoperative management
C) Open reduction and internal fixation using an endoscopic approach
D) Open reduction and internal fixation using a preauricular approach
E) Open reduction and internal fixation using a retroparotid approach
B. nonoperative management
When evaluating a patient with velopharyngeal dysfunction, which of the following studies is most helpful for analysis of lateral pharyngeal wall motion?
A) Lateral view videofluoroscopy
B) Nasometry
C) Nasopharyngeal endoscopy
D) Speech analysis
E) Static MRI
C. nasopharyngeal endoscopy
Comprehensive speech analysis is usually the first step in assessing speech and diagnosing velopharyngeal dysfunction but it does not analyze wall motion. Nasometry provides measurements of the modulation of the velopharyngeal opening area, but it does not identify the gap location. Lateral view videofluoroscopy helps analyze soft palate mobility. Static MRI allows for visualization of all velopharyngeal structures, but it does not assess function.
An 18-month-old female infant is evaluated because of oral asymmetry. A photograph is shown. This patient’s oral soft-tissue deficiency is best classified as which of the following Tessier cleft types?
A) No.4 B) No.5 C) No.6 D) No.7 E) No.8
D. number 7
Tessier No. 7 cleft is one of the more common and is often associated with craniofacial microsomia. Embryologically, it arises from failed fusion of the mandibular and maxillary prominences of the first branchial arch. The resultant soft-tissue defect can be quite variable, ranging from a subtle disruption of the oral commissure to a large open facial cleft extending from the oral cavity, across the cheek, and into the temporal region. Repair of the defect shown requires a multi-layered repair of the intraoral and commissure mucosa, all of the affected perioral musculature (especially the separated orbicularis oris muscle to establish oral continence), and the skin. Tessier No. 4 and No. 5 clefts extend from the upper lip to the lower eyelid, while the Tessier No. 6 cleft extends from the lateral lower eyelid into the ipsilateral cheek. Tessier No. 8 is a transverse cleft arising from the lateral canthal region.
A 3-month-old male infant is evaluated because of a midline congenital nasal mass. To determine the diagnosis and most appropriate management, which of the following imaging modalities would be most helpful in detecting associated brain abnormalities?
A) CT scan
B) Lateral cephalography
C) MRI
D) Skull x-ray study series
E) Ultrasonography
C. MRI
Midline congenital skull masses are most commonly dermoid cysts, encephaloceles, or gliomas.
A 12-year-old boy presents for evaluation after facial injury. His mother reports that he was involved in a mountain bike accident 2 months ago in which he sustained road rash and facial lacerations that were repaired in the emergency department. He experienced episodes of cellulitis accompanied by drainage from the sites of the repaired lacerations that did not improve with penicillin-based antibiotic therapy. CT scan without contrast disclosed retained foreign body in the subcutaneous tissue of the left cheek. The patient was then placed on cephalosporin without improvement. Which of the following is the most appropriate next step in management?
A) Addition of broad-spectrum antibiotics
B) Expectant management
C) Repeat CT scan with contrast
D) Surgical exploration
D. surgical exploration
A 2-year-old girl presents to the clinic preoperatively with an unrepaired cleft palate. The patient is meeting developmental milestones. Compared with a similar patient undergoing surgery at 1 year of age, this patient has an increased risk for which of the following?
A) Feeding difficulty
B) Fistula formation
C) Maxillary growth restriction
D) Postoperative airway complications
E) Velopharyngeal insufficiency
E. VPI
Earlier repair is associated with increased risk for maxillary growth disturbance. Later repair (beyond approximately 18 months of age) has been associated with worse speech outcomes and a higher risk for velopharyngeal insufficiency, leading to higher rates of secondary speech surgery.
Which of the following best describes the order of permanent teeth eruption?
A) Lower premolar, upper incisor, upper canine, upper first molar
B) Upper canine, upper incisor, lower premolar, upper first molar
C) Upper first molar, upper incisor, lower premolar, upper canine
D) Upper first molar, upper incisor, upper canine, lower premolar
E) Upper incisor, upper canine, lower premolar, upper first molar
C.Upper first molar, upper incisor, lower premolar, upper canine
A 6-month-old female infant with holoprosencephaly is brought by her parents to the clinic for follow-up. The patient has no history of seizures, and she has demonstrated successful weight gain and good oral intake. A photograph is shown. The patient’s parents desire closure of the lip defect when appropriate. Which of the following treatments is most likely to result in the best outcome with minimal risk?
A) Closure with an Abbe flap
B) Closure with an Estlander flap
C) Closure with a Karapandzic flap
D) Primary lip adhesion
E) Single-stage local tissue arrangement
E. single stage local tissue arrangement
lip adhesion and Karapandzic flap only address the lip and not the columella. The Abbe flap addresses the columella but necessitates two operations and, due to the decreased intraoral opening between the two procedures, increases airway and feeding risk. The three-in-one procedure as described by Zwahlen et al gets everything adequately closed in a single stage. An Abbe flap can always be performed later if warranted and if the child survives long enough to need it. While these deformities are rare, the need for a plastic surgeon to reconstruct these three-dimensional defects in this area is not. An Estlander flap is incorrect, as it is similar to a Karapandzic flap in that it does not address the nasal (columellar) defect
A 7-year-old girl is brought to the emergency department following a motor vehicle collision. The CT scan shown demonstrates fractures of the right orbital roof, inferior orbital rim, nasal bone, and left naso-orbital-ethmoid segment. There is no laxity of the medial canthal tendon with lateral traction on the upper eyelid (negative bowstring test). Surgical treatment is most strongly indicated for which of the following fractures?
A) Frontal bone
B) Inferior orbital rim
C) Nasal
D) Naso-orbital-ethmoid
E) None; surgery is not indicated
E. not indicated
The lateral cephalogram shown has a normal SNB angle of 80 degrees. These cephalometric findings are most consistent with which of the following?
A) Angle class II malocclusion
B) Mandibular prognathia
C) Maxillary retrusion
D) Overjet
E) Vertical maxillary excess
C. maxillary retrusion
In this cephalogram, SNB is given as normal and, thus, the mandibular position is not prognathic by definition. SNA is normally 2 to 3 degrees greater than SNB, but in this image, it is considerably less than SNB (negative ANB), indicating significant midfacial retrusion.
Which of the following options is most common as a cause of temporomandibular joint ankylosis in children?
A) Congenital
B) Infectious
C) Neoplastic
D) Radiation-induced
E) Rheumatic
A. congenital
* Rheumatic: 3%
* Radiation-induced: 3% * Infectious: 18%
* Neoplastic: 5%
A 44-year-old woman is evaluated because of pain and clicking anterior to the tragus with mouth opening. In the more common form of internal derangement of the temporomandibular joint, the disc is most often located in which of the following positions?
A) Anterior and medial
B) Inferior and lateral
C) Posterior and lateral
D) Posterior and medial
E) Superior and medial
A. anterior and medial
When planning a mandibular reconstruction with a free fibula flap, the use of computer-aided design/manufacturing (CAD/CAM) is more advantageous than conventional surgical planning because of a decrease in which of the following?
A) Flap loss
B) Hardware failure rate
C) Ischemia time
D) Orocutaneous fistula rate
E) Overall cost
C. ischemia time
A 45-year-old woman presents with a nasal defect after undergoing Mohs micrographic resection of a recurrent basal cell carcinoma. One year ago, the patient underwent a smaller excision of a basal cell carcinoma in the same area, followed by single-stage reconstruction with a flap from the ipsilateral cheek. Examination shows a transmural defect extending into the nasal cavity. A photograph is shown. Reconstruction of the nasal lining using an interpolated septal flap is planned, along with autologous cartilage grafting to provide structural support. Which of the following is the most appropriate technique for cutaneous reconstruction in this patient?
A) Cervicofacial rotation advancement flap
B) Full-thickness skin graft
C) Ipsilateral interpolated nasolabial flap
D) Paramedian forehead flap
E) “Waltzing” tubed flap
D. paramedian forehead flap
The patient has a full-thickness nasal defect in which a vascularized flap is used for nasal lining with overlying cartilage grafting. Cutaneous reconstruction will also require a vascularized flap as opposed to a graft due to the cartilage grafting. Given the size and location of the defect, an interpolated option would be best to preserve the alar facial sulcus, which would otherwise be obliterated by a cervicofacial rotation advancement flap or other adjacent tissue transfers. In the setting of a prior reconstruction with an ipsilateral cheek flap, it would be better to avoid an interpolated ipsilateral cheek flap, since the vascularity may be compromised. Although tubed flaps can be “waltzed” from distant sites to the nose, a paramedian forehead flap is the best option since it can be performed in the fewest number of stages.
Which of the following structures is formed from the same branchial arch as the levator veli palatini muscle of the soft palate?
A) Inferior parathyroid gland
B) Lesser horn of the hyoid bone
C) Maxillary artery
D) Styloid process
E) Superior laryngeal nerve
E. superior laryngeal nerve
Each of the six branchial arches gives rise to a branch of the aortic arch, a cranial nerve, muscular structures, and skeletal structures. The fourth branchial arch gives rise to the right proximal subclavian artery, the aortic arch, the vagus nerve, the superior laryngeal nerve, cricothyroid muscles, laryngeal cartilages, the superior parathyroid glands, and the intrinsic muscles of the velum, including the levator veli palatini.
The inferior parathyroid glands are derived from the third branchial arch, along with the common carotid artery, internal carotid artery, glossopharyngeal nerve (IX), stylopharyngeus muscle, greater horn of the hyoid bone, and thymus.
The lesser horn of the hyoid bone is derived from the second branchial arch.
The maxillary artery is derived from the first branchial arch, along with the trigeminal (V) nerve, the muscles of mastication, anterior belly of the digastric muscle, tensor tympani, tensor veli palatini, mylohyoid, mandible, incus and malleus, maxilla, vomer, zygoma, and temporal bone.
The styloid process is derived from the second branchial arch, along with the stapedial and hyoid arteries, the facial (VII) nerve, the muscles of facial expression, the stapes, the lesser horn of the hyoid bone, and the crypts of the palatine tonsils.
A 30-year-old woman is referred by her dermatologist for evaluation of scar alopecia after undergoing excision of a nevus over the right eyebrow. Examination shows absence of one-third of the right eyebrow hair. The patient undergoes single-follicle hair transplantation to reconstruct the eyebrow. Preoperative and postoperative photographs are shown. Four weeks later, the patient returns to the clinic because all of the transplanted hair has fallen out. Which of the following is the most likely cause of this patient’s hair loss?
A) Acute transplant rejection
B) Hair follicle shedding prior to regrowth
C) Inappropriate revascularization of scar tissue
D) Noncompliance with postoperative instructions
E) Postoperative cellulitis
B. Hair follicle shedding prior to regrowth
A 6-year-old boy is evaluated because of a scalp lesion. The lesion was present at birth and has not changed in character or appearance. A photograph is shown. The boy’s parents were told by their pediatrician that this lesion could become malignant. This patient has the highest risk for which of the following malignant tumors?
A) Basal cell carcinoma
B) Malignant melanoma
C) Merkel cell tumor
D) Pleomorphic dermal sarcoma
E) Squamous cell carcinoma
A. basal cell
This is a nevus sebaceus (of Jadassohn), also known as an organoid nevus, a congenital malformation that arises from the pilosebaceous follicular units. most commonly its located on the scalp where it almost invariably presents as a flat, discolored plaque-like lesion with overlying alopecia. Over time, these lesions can thicken and transform into various benign tumors and malignant tumors. Benign tumors include syringocystadenoma papilliferum, trichoadenoma, and trichoblastoma, while the most common malignant tumor is basal cell carcinoma, followed a distant second by squamous cell carcinoma.
An otherwise healthy 21-month-old female infant is evaluated because of an insidious and progressive decline in head circumference percentile that began at age 6 months. Family history is significant for Crouzon syndrome. A head circumference chart and CT scan are shown. Which of the following best describes the findings on the CT scan?
A) Cloverleaf skull
B) Frontal lobe hypoplasia
C) Normal cranial shape
D) Patent cranial sutures
E) Turribrachycephaly
C. normal cranial shape
progressive postnatal pansynostosis (PPP)- form of craniosynostosis
A. advance point A, advance point B, advance gnathion
