Reconstruction

Question 1

What is the minimum amount of time a parotid stent be kept in place after a ductal repair? A. 2-4 weeks B. 6-8 weeks C. 10-12 weeks D. 16-18 weeks

Answer 1

Answer: A Rationale: Deep lacerations of the cheek can injure the parotid duct and facial nerve branches. The duct should be explored. Proximal and distal ends are identified, and a stent is sutured to the intraoral mucosa to prevent accidental displacement while the duct heals and is removed 2 to 4 weeks. This is sufficient time to allow for re-epithelialization of the severed duct. If the proximal portion of the duct cannot be located, a pressure dressing is applied to decrease the chances of a sialocele. Multiple aspirations of accumulated saliva may be a necessary part of this regimen. Use of antisialogogues (such as oral glycopyrrolate) is always a recommended adjunct when repairing a severed salivary gland duct. Reference: Karas, ND. Surgery of the salivary ducts. Atlas Oral Maxillofac Surg Clin North Am. 1998 Mar;6(1):99-116 Ward Booth, P. Maxillofacial Trauma. Primary management of soft tissue trauma and nerve reconstruction. 213-255Churchill Livingstone 2003.

Question 2

What is the largest percent loss of an upper lip avulsive defect that can be closed primarily without compromising function and aesthetics? A. 20 % B. 30 % C. 40 % D. 50 %

Answer 2

Answer:B Rationale: Because of great tissue elasticity, an avulsive defect of approximately 30% of the upper or lower lip can be reconstructed with primary closure without compromising function and esthetics. Defects greater than 30% require local and regional flaps in order to prevent microstomia. Reference: Naumann, H.H. Head and Neck Surgery. Volume 1: Face, Nose and facial Skull, Part I. Surgical Management of skin defects of the scalp, forehead, cheeks and lips. P 41-94. Thieme 1995. Mathes, S. Plastic Surgery. Volume 3: The Head and Neck, Part 2. Second Edition. Elsevier 2006.

Question 3

How long after inferior canaliculus laceration repair and intubation should the stent remain in place in the adult patient? A. 1-2 weeks B. 4-6 weeks C. 7-10 weeks D. 12-16 weeks

Answer 3

Answer: D Rationale: Inferior canaliculus injuries need repair within 24-48 hours in order to prevent epiphora. Repair of this kind of injuries is usually carried out by loop intubation with the punctate being initially cannulated with silastic stents. The stents extend from the puncta through the nasolacrimal duct and emerge in the inferior meatus, and should remain in place for at least 3 months in the adult in cases of pediatric injuries, the same procedure is performed; however, the stent can be removed in a shorter amount of time. Reference: Ward Booth, P. Maxillofacial Trauma Trauma. Primary management of soft tissue trauma and nerve reconstruction. 213-255 Churchill Livingstone 2003. Miloro, M. et al, Peterson’s Principles of Oral and Maxillofacial Surgery. Soft Tissue injuries, p357-370. Second Edition, BC Decker 2004.

Question 4

A patient has an upper eyelid laceration with fat herniating from the wound. Injury to which of the following can be eliminated? A. Levator palpebrae superiorus B. Globe C. Sub-orbicularis oculi fat D. Retro-orbicularis oculi fat

Answer 4

Answer: C Rationale: SOOF, or the sub-orbicularis oculi fat is located in the lower lid region between the periosteum and the orbicularis oculi muscle. It should not be involved in an upper lid injury. All other choices might occur in an upper eye lid laceration. Reference: Turk JB, Goldman A. SOOF lift and lateral retinacular canthoplasty. Facial Plast Surg. 17, 37, 2001. Hwang SH, Hwang K, Jin S, et al. Location and Nature of Retro-Orbicularis Oculus Fat and Suborbicularis Oculi Fat. J Craniofac Surg. 2007 Mar; 18(2):387-390. 

Question 5

What is the minimal pressure (in pounds per square inch) required during irrigation to mechanically disrupt bacterial adherence to a wound surface? A. 7 lbs (3.18 kg) B. 10 lbs (4.55 kg) C. 15 lbs (6.82 kg) D. 20 lbs (9.09 kg)

Answer 5

Answer: A Rationale: To be clinically effective, irrigants must be delivered with a fluid jet impacting a wound with 7 lb of psi. This pressure is the adequate for removing adherent bacteria from a wound. This amount of pressure can be generated from a pulsatile irrigation apparatus. Reference: Fonseca, Oral & Maxillofacial Trauma, Vol II, 2005, chapter 25, Management of soft tissue injuries 751-820. Tobin GR. Closure of contaminated wounds. Surg Clin N Am, 64, 639-652, 1984.

Question 6

Whitnallís ligament attaches to which of the following structures? A. Whitnallís tubercle B. Lockwoodís suspensory ligament C. Lateral horn of levator aponeurosis D. Orbital lobe of the lacrimal glands

Answer 6

Answer: D Rationale: There are 4 structures attaching to the lateral retinaculum of the Whitnall’s tubercle: Lockwood’s suspensory ligament, lateral horn of levator aponeurosis, check ligament of lateral rectus muscle, and posterior limb of lateral canthal tendon. Whitnall’s ligament, the suspensory ligament of the upper lid, attaches around the orbital lobe of the lacrimal gland. Reference: Jelks GW, Glat PM, Jelks EB, et al. The inferior retinacular lateral canthoplasty: A new technique. Plast Reconstr Surg 100; 1997: 1262-1275.

Question 7

The first evidence of systolic hypotension is seen in which class of hemorrhagic shock? A. Class I B. Class II C. Class III D. Class IV

Answer 7

Answer: C Rationale: Class III statatic hemorrhagic shock is distinguished by 30%-40% blood loss and the first indication of hypotension. Class I and II hemorrhagic shock do not display any reduction of blood pressure. Reference: Advanced Trauma Life Support. American College of Surgeons Committee on Trauma. Shock, 87-107, 2005 Krausz MM. Initial resuscitation of hemorrhagic shock. World J Emerg Surg. 2006 Apr 27;1. 

Question 8

Which of the following can occur following placement of a tissue expander in the scalp? A. Epidermal hypoplasia B. Increase in dermal thickness C. Atrophy of fat D. Hyperplasia of skeletal muscle

Answer 8

Answer: C Rationale: Following placement of a tissue expander in the body, the following histologic changes occur: thickened epidermis, decrease in thickness of dermis, no changes in hair follicles or sebaceous glands, decrease in thickness of skeletal muscle, increase in capillaries, and fat atrophy. Reference: Marks MW, Argenta LC. Skin expansion in reconstructive surgery. Facial Plastic Surg, 1988, 301-311. Hoffman JF. Tissue expansion in the head and neck. Facial Plast Surg Clin North Am. 2005 May,:315-24.

Question 9

Scar modification using a 60í Z-Plasty technique will increase the over length of the laceration by how much? A. 35% B. 45% C. 75% D. 95%

Answer 9

Answer: C Rationale: Z-plasty is used to rearrange a wound. A 30’ Z-plasty will increase the overall length of a wound by 25%, a 45’ Z-Plasty by 50%, and a 60’ Z-plasty by 75%. The long axis of the wound is rotated 90 degrees and the entire length of the incision is lengthened compared to the length of the excised scar. Reference: Hove CR, William EF 3rd, Rogers BJ. Z-plasty: a concise review. Facial Plast Surg. 2001 Nov: 289-94. Davis WE, Boyd JH. Z-Plasty. Otolaryngol Clin N Am 1990, 23:880-885. 

Question 10

What is the most commonly isolated organism found in mammalian animal bites? A. Escherichia coli B. Clostridium tetani C. Pasteurella multocida D. Fusobacterium nucleatum

Answer 10

Answer: C Rationale: Although multiple organisms have been isolated from animal bites, 50-75% of all bites contain Pasteurella multocida. This aerobic organism is especially prevalent in cat bites. Beta lactam antibiotics are indicated for the treatment of such wounds. Initial management of such wounds should include Debridement and irrigation. Reference: Presutti RJ. Bite wounds. Early treatment and prophylaxis against infectious complications. Postgrad Med. 1997 Apr; 101(4):243-4, 246-52, 254. Fonseca. Oral and Maxillofacial Trauma. Chapter 27, 843-862. 2005. Stefanopoulos PK, Tarantzopoulou AD. Facial bite wounds: management update. Int J Oral Maxillofac Surg. 2005; 34:464-72.

Question 11

What is the mechanism for development of coagulopathy following diffuse axonal injury (DAI)? A. Lack of production of factor V B. Release of tissue thromboplastin C. Release of antithrombin III D. Excessive production of prothrombin

Answer 11

Answer: B Rationale: DAI is a common occurrence following traumatic deceleration injuries of the brain. Initially, DAI does not show specific CT or MRI findings. However with time, diffuse edema if seen on CT scans. Release of tissue thromboplastin by damaged brain matter signals the clotting cascade leading to depletion of coagulation factors. Coagulopathy is a common finding following DAI. Reference: Advanced Trauma Life Support. American College of Surgeons Committee on Trauma. Head Trauma, 181-206, 2005 Greenberg MS. Handbook of Neurosurgery. Head Trauma, 690-753, 1997

Question 12

Which artery supplies the condylar head following a subcondylar fracture? A. Masseteric B. Medial pterygoid C. Lateral pterygoid D. Buccal

Answer 12

Answer: C Rationale: The axial blood supply to the mandibular condyle is via the lateral pterygoid artery. This artery supplies the muscle which is intimately associated and attached to the condylar head and neck. Reference: Fonseca. Oral and Maxillofacial Trauma. Basic Anatomy of the Head and Neck, 281-328, 2005. Janfaza P et al. Surgical anatomy of the head and neck. Scalp, Cranium and Brain, p 49- 148, 2001.

Question 13

A 7.5 cm segmental defect of the mandible would be expected to require the harvest of what volume of corticocancellous bone for reconstructive surgery? A. 35-45 cc’s B. 75-85 cc’s C. 105-115 cc’s D. >115 cc’s

Answer 13

Answer: B Rationale: It is generally recommended that a segmental defect of the mandible be reconstructed with 1 cc of corticocancellous bone per every 1 mm of defect. Adding 10% to this harvested volume will ensure the procurement of sufficient bone. As such, a 7.5 cm defect, or 75 mm, would be expected to require 75-85 cc’s of bone.

Question 14

The best donor site for harvest of bone for reconstruction of a 7.5 cm segmental defect of the mandible would be which of the following? A. Clavicle B. Posterior ilium C. Anterior ilium D. Tibia

Answer 14

Answer: B Rationale: The harvest of 75-85 cc’s is predictably possible only from the posterior ilium. The clavicle is not generally described as a donor site for mandibular reconstruction. The anterior ilium is expected to yield approximately 30 – 40 ml of cancellous bone, while the tibia would be expected to yield approximately 15 – 20 ml. Therefore, a 7.5 cm defect of the mandible can only be predictably reconstructed with a harvest of bone from the posterior ilium.

Question 15

The administration of hyperbaric oxygen is planned for a patient scheduled for reconstruction of a segmental defect of the mandible with corticocancellous bone where the lower third of the face was in the direct field of radiation therapy. How many treatments would be recommended? A. 10 preoperatively, none postoperatively B. 20 preoperatively, 10 postoperatively C. 20 preoperatively, 20 postoperatively D. 30 preoperatively, 10 postoperatively

Answer 15

Answer: B Rationale: The time honored protocol for the administration of HBO to an irradiated patient in preparation for mandibular reconstruction is 20 preoperative treatments followed by surgery and 10 postoperative treatments. This protocol assumes that a diagnosis of osteoradionecrosis of the mandible has not been met. When such a diagnosis is met, the patient receives 30 treatments of HBO initially followed by re- evaluation.

Question 16

Which of the following media is best for corticocancellous bone storage following the harvest of the bone? A. D5W B. Hypertonic saline C. Sterile water D. Normal saline

Answer 16

Answer: D Rationale: An isotonic solution is crucial to avoid rupture of bone cells. The only isotonic solution among the answers is normal saline. D5W and sterile water are hypotonic, while hypertonic saline is hypertonic. Hypotonic and hypertonic solutions do not support the physiology of harvested bone.

Question 17

What length of time is permitted between harvest to placement to ensure the survival of a majority of harvested cells in a corticocancellous bone graft? A. 1 hour B. 2 hours C. 3 hours D. 4 hours

Answer 17

Answer: D Rationale: Harvested bone cells show about a 95% viability up to four hours at OR temperatures.

Question 18

Which of the following is true regarding reconstruction of the maxilla following extirpative tumor surgery? A. Maxillofacial prostheses are rarely indicated, as they are essentially non-functional. B. Restoration of facial contour is of little importance, regardless of the type of procedure and/or prosthesis, since restoration of function is the key to success. C. Separation of the oral mucosa from the nasal-antral mucosa is a significant consideration for any surgical restorative procedure. D. Bony reconstruction should be accomplished as soon as possible after initial malignant tumor surgery, to prevent scar contracture and provide for the best result.

Answer 18

Answer C Rationale: Separation of the oral mucosa from the nasal-antral mucosa is very important. Saliva is kept out of the nasal cavity. Speech and function are usually improved by this separation. The quality of the mucosa is different as well, with an obturator better adapted to the oral mucosa.

Question 19

The primary limiting factor for the length of bone that can be harvested in a vascularized transfer of fibula is which of the following? A. Stability of the ankle and knee joint B. Length of the peroneal artery C. Length of the venae comitantes D. There is no limit, the entire fibula can be transferred

Answer 19

Answer: A Rationale: The primary role of the fibula is stabilization of the knee and ankle joint. Five to six centimeters of fibula should be left proximally and distally for this reason to prevent instability of these joints. The peroneal nerve also limits the proximal dissection, but that is not a choice. The take-off of the peroneal artery from the posterior tibial artery limits the pedicle length, but not the bone length. Likewise, the venae comitantes can be harvested along the length of the arterial pedicle, but does not limit the bone stock. Although controversial, some surgeons do feel the entire proximal fibula can be harvested, including the portion that contributes to the knee, however, the distal portion must always be preserved for ankle stability. Therefore, A is the best choice.

Question 20

Which of the following nerves is most commonly harvested with the radial forearm fasciocutaneous flap and reconstructed when attempting to provide a sensate flap reconstruction? A. Ulnar nerve B. Lateral antebrachial cutaneous nerve C. Medial antebrachial cutaneous nerve D. Radial Nerve

Answer 20

Answer: B Rationale: The lateral antebrachial cutaneous nerve provides sensation to the territory harvested most commonly with the RFFF. It can be reconstructed to the lingual nerve in attempt to provide a sensate flap. Harvest of the ulnar nerve would lead to excessive morbidity as it is a motor and sensory nerve. It would affect the ability to flex and abduct the wrist and movement of the thumb. Fine movements of the fingers would also be affected. The radial nerve is specifically protected in the harvest of the radial forearm flap, and indeed the subfascial plane of dissection must be broken to preserve this nerve. Finally, the medial cutaneous antebrachial nerve can be harvested, but it does not supply the territory typically harvested.

Question 21

Anastamosis of which pair of vessels provides for in-flow and out-flow for a vascularized fibula flap? A. Posterior tibial artery and vein B. Anterior tibial artery and vein C. Popliteal artery and popliteal vein D. Peroneal artery and venae commitans

Answer 21

Answer: D Rationale: The peroneal artery and its associated venae commitans make up the vascular pedicle to the vascularized fibula flap. The popliteal artery divides into the anterior tibial and posterior tibial arteries. The posterior tibial then gives off the peroneal artery, which supplies the vascular territory of the fibula flap. Harvest of the popliteal artery would leave the lower leg without a blood supply. The posterior tibial artery is preserved to maintain vascular blood supply to the lower leg.

Question 22

Transfer of a vascularized radial forearm flap without confirming intact communication between the superficial and deep palmer arches through an Allen’s test will result in vascular compromise to which of the following? A. Palm B. Thumb C. Middle finger D. 5th digit

Answer 22

Answer: B Rationale: Sacrifice of the radial artery relies on an intact communication between the superficial and deep palmer arches. This is typically confirmed pre-operatively by an Allen’s test. The technique is as follows: 1. Elevate the patient’s hands above heart 2. Occlude radial and ulnar arteries 3. Have the patient open and close fist several times 4. Lower the hand below heart 5. Release ulnar artery and time blood flow return to hand 6. Repeat with radial artery If there is no communication between the superficial and deep palmar arches, sacrifice of the radial artery will result in vascular compromise to the thumb. The palm, middle finger and 5th digit are supplied by the ulnar artery.

Question 23

Salivary gland involvement in conjunction with xerostomia or xerophthalmia are required clinical findings to establish the diagnosis of which of the following? A. Sjogren’s syndrome B. Sialosis C. Sarcoidosis D. Lymphoma

Answer 23

Answer: A Rationale: Sjogren’s syndrome is an autoimmune disease that causes a lymphocyte-mediated destruction of exocrine glands. This results in a decrease in glandular secretion of the salivary glands (xerostomia) and the lacrimal glands (xerophthalmia).

Question 24

Which of the following entities is characterized by diffuse bilateral parotid enlargement secondary to nutritional changes? A. Sjogren’s syndrome B. Sarcoidosis C. Lymphoepithelial lesions D. Sialosis

Answer 24

Answer: D Rationale: Sialosis is a generalized hypertrophy of the individual acinar cells that results in bilateral enlargement of the parotid gland. It is not associated with an immune disorder or neoplastic process. The parotid enlargement is usually secondary to nutritional changes brought about by alcoholism or bulimia. An incisional parotid biopsy is indicated to rule out Sjogren’s disease, sarcoidosis and lymphoma.

Question 25

A black female patient presents with history of easy fatigability, anorexia, and hilar adenopathy with parotid and lacrimal gland enlargement. The most likely diagnosis is: A. sarcoidosis. B. lymphoma. C. Sjogren’s syndrome. D. anorexia.

Answer 25

Answer: A Rationale: Sarcoidosis is a systemic disease characterized by infiltration of tissues with sarcoid granulomas. In Heerfordt’s syndrome, clinical enlargement of the parotid and lacrimal gland (sarcoid infiltrate) is seen together with retinal damage. Chronic sarcoidosis has a 6:1 black to white patient ratio and a slight female predilection. Anorexia, lethargy and pulmonary involvement with hilar adenopathy are a common clinical finding.

Question 26

Which of the following statements regarding benign lymphoepithelial parotid lesions is true? A. It is a pre-malignant condition with a high likelihood of malignant transformation. B. Total parotidectomy is often indicated. C. May present as an isolated salivary gland abnormality or a manifestation of Sjogren’s disease. D. It is often associated with a viral infection.

Answer 26

Answer: C Rationale: Benign lymphoepithelial lesions typically present as a unilateral or bilateral parotid gland swelling resulting from a diffuse benign infiltration of lymphoid cells. It is believed that these lesions develop as a result of an immunologic abnormality. These lesions can also be seen in association with Sjogren’s syndrome. There is no specific treatment for these lesions other than follow-up and observation given the small potential for malignant transformation and its relationship with Sjogren’s syndrome.

Question 27

Karapandzic type flaps might be chosen for lip reconstruction under which of the following situations? A. Only for the upper lip B. For defects less than one third of the lower lip C. For closure of lower lip defects up to 60% of the lower lip D. Are best avoided for lower lip reconstruction as nerves and primary vessels are cut

Answer 27

Answer: C Rationale: Karapandzic flaps are excellent single stage closures of moderately sized defects of the lower lips, especially in homebound patients and patients with a natural dentition. This flap transfers vascularized tissue to close lower lip defects up to 60% of its length. The result will be upper and lower lips unequal in size, and with a slightly retruded lower lip relative to the upper lip.

Question 28

Which of the following best describes the use of an Abbe flap for lip reconstruction? A. Should be limited to defects over 25% of upper lip loss B. Is a random pattern flap C. Should be restrained with intermaxillary fixation to prevent dislodgement D. Should be cut down (divided and inset) no sooner than 5 weeks

Answer 28

Answer: A Rationale: An Abbe flap is a local pedicled axial pattern flap for upper and lower lip reconstruction. It is ideally used for defects greater than 25% of upper lip loss and approximately 33% of lower lip loss. The pedicle is divided at about 2-3 weeks.

Question 29

Which of the following best describes the use of a rhomboid flap in facial reconstruction? A. Places all final scars in resting skin tension lines B. Is dependent on having the pivot point move in the lines of maximum extensibility (opposite the RSTL) C. Does not distort any adjacent tissues D. Is perfect for most forehead defects

Answer 29

Answer: B Rationale: The rhomboid flap is a transpositional flap. As such, the pivot point, where the greatest degree of tension exists, must move in extensible lines. This flap will not place all scars in resting skin tension lines, and distortion of adjacent tissues will occur.

Question 30

Which of the following best describes the advantages of a full thickness skin graft in facial reconstruction compared to a split thickness skin graft? A. More contracture of a full thickness skin graft compared to a split thickness skin graft B. More predictable healing of a full thickness skin graft compared to a split thickness skin graft C. Less postoperative care for the donor site of a full thickness skin graft compared to a split thickness skin graft D. Fewer donor site infections of a full thickness skin graft compared to a split thickness skin graft

Answer 30

Answer: C Rationale: The main advantages of a full thickness skin graft over a split thickness skin graft for facial reconstructive surgery include less contracture of the healing graft, and less labor regarding the donor site’s postoperative management. This is owing to the ability to primarily close the donor site of a full thickness skin graft, while the donor site of a split thickness skin graft must heal by tertiary intention. During this time, the split thickness skin graft donor site must be dressed with an occlusive dressing such as Opsite or Tegaderm. With this in mind, the potential for postoperative infection is such that the closed wound may develop infection, while the defect pertaining to the split thickness skin graft is open, and therefore less likely to become infected postoperatively.