Dermatologic and Cosmetic Surgery Flashcards
1- These lesions were biopsied and demonstrated a grenz zone and mixed inflammatory infiltrate composed of eosinophils, neutrophils, plasma cells and lymphocytes, with RBC extravasation. Which of the following treatment modality has shown efficacy in treating this condition?
A. Pulsed dye
B. Nd:YAG
C. Alexandrite
D. Intense pulsed light
E. Excimer
Correct choice: A. Pulsed dye
Explanation: The histopathology describes granuloma faciale: dense, often nodular infiltrate in the mid dermis with a Grenz zone and mixed infiltrate of eosinophils, neutrophils, plasma cells, mast cells, and lymphocytes, with extravasated RBCs. Vascular ectasia with fibrin deposition may be seen. There are several reports of treatment with pulsed dye laser.
2- Which combination of chemical peel therapies is appropriate for the treatment of epidermal melasma?
A. Phenol and trichloroacetic acid 20%
B. Trichloroacetic acid 35% and Jessner’s solution
C. Multiple coats of trichloroacetic acid 35%
D. Trichloroacetic acid 20% and Septisol
E. Ascorbic acid 5% and trichloroacetic acid 20%
Correct choice: E. Ascorbic acid 5% and trichloroacetic acid 20%
Explanation: Superficial chemical peels can be used in treatment of melasma. 5% ascorbic acid can reduce the activity of tyrosinase to treat melasma. Soliman et al compared the treatment of melasma using a 20% TCA peel alone vs a combination 20% TCA peel with topical 5% ascorbic acid. When comparing the TCA alone-treated patients to patients treated with the combination TCA and ascorbic acid peel, a significant reduction in pigmentation was noted in the combination peel patients. trichloroacetic acid 35% and Jessner’s solution combination was used for medium depth peeling for mild to moderate photoaging. Phenol is a deep chemical peel, and part of the Baker– Gordon formula. Septisol is a surfactant that reduces skin tension and is used in deep chemical peels (part of the Baker–Gordon formula). Multiple coats of TCA 20% as well as TCA 35% can essentially act like a medium depth peel. Multiple coats of TCA 35% can cause post inflammatory hyperpigmentation in darker skin types.
3- The following patient recently underwent submental injections of deoxycholic acid (Kybella). One day later, she noticed an inability of her right lip depressors to pull her lip downward and laterally, particularly when smiling. What is the next best step?
A. Watchful waiting
B. Inject the opposite side to achieve symmetry
C. Obtain an MRI
D. Inject intralesional corticosteroids
E. Administer non-steroidal anti-inflammatory agents
Correct choice: A. Watchful waiting
Explanation: Kybella (deoxycholic acid) is an FDA-approved treatment for injection into the submental area. Cases of marginal mandibular nerve injury manifesting as an asymmetric smile or facial muscle weakness were reported in 4% of subjects in clinical trials. All cases resolved spontaneously within a median of 44 days. It should not be injected into, or in close proximity to, the marginal mandibular branch of the facial nerve. Given the results of the clinical trials for deoxycholic acid, the best initial step in management is watchful waiting and close monitoring of the patient. If the patient does not improve in the next 1-2 months, additional investigations can be considered.
A- 35 year-old woman comes to your office for treatment of melasma. She has tried topical creams with minimal improvement and you recommend a chemical peel. Which of the following does require neutralization?
A. Jessner’s
B. TCA
C. Salicylic acid
D. Glycolic acid
E. Baker-Gordon peel
Correct choice: D. Glycolic acid
Explanation: Glycolic acid peels required neutralization with sodium bicarbonate. The others listed do not require neutralization. All alpha hydroxy acids need neutralization, including glycolic acid, lactic acid and mandelic acid. The remaining answer choices do not require neutralization.
5-What type of flap does this image represent?
A. A-to-T advancement flap
B. Island pedicle flap
C. Rotation flap
D. Transposition flap
E. Interpolation flap
Correct choice: B. Island pedicle flap
Explanation: This image shows the specialized advancement flap referred to as an island pedicle, or V-to-Y, flap. The “island” is when skin is completely incised on all 3 sides. Its rich vascular supply comes from subcutaneous/muscular pedicle. It provides exceptional flap viability and mobility.This image does not show the other listed flaps.
- A- patient comes in for endovenous laser ablation for varicose veins. You choose a 1320nm or 1450 nm laser. Which is the target chromophore for these lasers?
A. oxygenated hemoglobin
B. oxygen
C. water
D. melanin
E. deoxygenated hemoglobin
Correct choice: C. water
Explanation: 810–1064 nm laser (targetting more Hb), as well as 1320, 1440 and 1500 nm lasers (targetting more water) can be used in Endovenous Laser Ablation. The latter wavelengths target tissue water within the vein wall, causing fibrosis, results in a more controlled, and uniform heating. The absorption of water increases above 1000nm. Deoxygenated hemoglobin is the main chromophore of the 810- and 980-nm lasers. Oxygenated hemoglobin peaks in absorption between 400-600nm (vascular lasers). Melanin has a downward sloping absorption curve from 300-1000nm. Oxygen is not a target chromophore.
7-The most appropriate laser to initially treat a port-wine stain on an infant’s cheek would have which of the following wavelengths?
A. 488 nm
B. 510 nm
C. 585 nm
D. 694 nm
E. 755 nm
Correct choice: C. 585 nm
Explanation: The 585 nm pulsed dye laser (PDL) targets intravascular oxyhemoglobin and is considered the first-line treatment of choice for most benign vascular lesions, including port-wine stains. The original PDL had a wavelength of 577 nm which was later modified to 585 nm to achieve deeper penetration yet still maintain vascular specificity. The Argon laser can produce a wavelength of 488 nm, which predominantly targets melanin as the chromophore and thus can be used to treat pigmented lesions. The Argon laser was previously used for port-wine stains, but it had increased rate of scarring and has largely fallen out of use. It is important to note that certain pulsed dye lasers can operate at a shorter wavelength of 510 nm, which also targets melanin as the chromophore. The Ruby laser produces a wavelength of 694 nm, which targets melanin too. The Alexandrite laser produces a wavelength of 755 nm, thereby predominantly targeting melanin as well. The Alexandrite laser can be used for dark or PDL-resistant port-wine stains.
- A- 68-year-old male presents with a tattoo that he has had for >50 years that is a dark gray/black. What is the desired clinical endpoint when treating tattoos or pigmented lesions with Q-switched lasers?
A. Tissue whitening
B. Perifollicular edema
C. Purpura
D. Mottled pigmentation
E. Erythema
Correct choice: A. Tissue whitening
Explanation: Tissue whitening is the desired clinical endpoint when operating a Q-switched laser. Perifollicular edema, purpura, mottled pigmentation and erythema are not clinical endpoints when operating a Q-switched laser.
9-What is the mechanism of action of Onabotulinumtoxin-A?
A. Inhibits exocytosis of pre-synaptic epinephrine
B. Inhibits endocytosis of post-synaptic epinephrine
C. Inhibits exocytosis of pre-synaptic acetylcholine
D. Inhibits endocytosis of post-synaptic acetylcholine
E. Increases synaptic breakdown of acetylcholine
Correct choice: C. Inhibits exocytosis of pre-synaptic acetylcholine
Explanation: Botulinum toxin exerts its effect by cleaving key proteins required for nerve activation. First, the toxin binds specifically to nerves which use the neurotransmitter acetylcholine. Once bound to the nerve terminal, the neuron takes up the toxin into a vesicle. As the vesicle moves farther into the cell, it acidifies, activating a portion of the toxin which triggers it to push across the vesicle membrane and into the cell cytoplasm. Once inside the cytoplasm, the toxin cleaves SNARE proteins preventing the cell from releasing vesicles of acetylcholine. This stops nerve signaling, leading to paralysis.
- A- 60-year-old female presents with numerous facial lentigines due to photo damage. She would like to try cosmeceuticals for pigment lightening in addition to hydroxy acids. Which of the following cosmeceuticals is not a pigment lightener?
A. Green tea
B. Arbutin
C. Licorice extract
D. Vitamin C
E. Aleosin
Correct choice: A. Green tea
Explanation: Green tea is an antioxidant and contains antioxidant polyphenols: epicatechin, epicatechin-3-gallate, epigallocatechin, epigallocatechin-3-gallate.
B - Arbutin: Arbutin is a naturally occurring gluconopyranoside; decreased tyrosinase activity and may inhibit melanosomal maturation.
C- Licorice extract: Licorice extract contains liquiritin and isoliquertin, which disperse melanin, and glabridin, which inhibits tyrosinase.
D - Vitamin C: Vitamin C may interrupt melanogenesis by interacting with copper ions.
E - Aleosin: Aleosin is a naturally occurring hydroxymethylchromone; inhibits tyrosinase by competitive inhibition.
11- What is the best treatment option for the lesion below?
A. Excision with repair
B. Mohs with repair
C. 1064-nm Nd:YAG (long-pulsed)
D. Erbium:YAG
E. Radiation
Correct choice: C. 1064-nm Nd:YAG (long-pulsed)
Explanation: Long-pulsed 1064 nm Nd:YAG is the best treatment option of those listed for the benign lesion of venous lake of the lip. Excision, Mohs, and radiation are not indicated for benign lesions. Erbium:YAG is ill suited for the treatment of a vascular papule of the lip.
12- Botulinum toxin A cleaves which protein to exert its effects?
A. Synaptobrevin
B. Syntaxin
C. Acetylcholinesterase
D. SNAP-25
E. Synaptophysin
Correct choice: D. SNAP-25
Explanation: Choice D is correct. Botulinum toxins A, C, E catalyze cleavage of SNAP-25 protein. Botulinum toxins B, D, F, and G catalyze cleavage of synaptobrevin (or vesicle- associated membrane protein, VAMP [Choice 1]).
Syntaxins are a family of membrane integrated proteins participating in exocytosis. They are not targeted by botulinum toxins. Acetylcholinesterase cleaves acetylcholine and is not targeted by botulinum toxin. Synaphtophysin is a synaptic vesicle protein with uncertain function. It is often stained when searching for cells of neuroendocrine origin.
13- After treating this patient with Onabotulinumtoxin-A, they return to clinic complaining of their right upper eyelid drooping and intefering with their vision. What is the mechanism of action of the medicated eye drops which has been shown to be beneficial when this adverse effect occurs?
A. alpha agonist which results in contraction of the superior tarsal muscle
B. alpha agonist which results in relaxation of the superior tarsal muscle
C. alpha antagonist which results in contraction of the superior tarsal muscle
D. alpha antagonist which results in relaxation of the superior tarsal muscle
E. beta agonist which results in contraction of the superior tarsal muscle
Correct choice: A. alpha agonist which results in contraction of the superior tarsal muscle
Explanation: Eyelid ptosis is a known potential complication of glabellar treatment with neurotoxins, likely due to diffusion of medication into the orbit and affecting the levator palpebrae superioris muscle. Apraclonidine is an alpha-agonist which can improve the ptosis by causing contraction of the superior tarsal muscle (occasionally referred to as Müller’s muscle). The other answer choices do not describe the mechanism of action of apraclonidine.
14- Which of the following criteria carries the worst prognosis for a patient with a squamous cell carcinoma?
A. Size of tumor > 1 cm
B. Verrucous carcinoma subtype
C. Invasion of nerve 0.15 mm in diameter
D. Anatomic location
E. Immunosuppression
Correct choice: C. Invasion of nerve 0.15 mm in diameter
Explanation: Many factors contribute to the aggressive behavior of cutaneous squamous cell carcinoma. For example, tumors in immunosuppressed patients and tumors with the histologic subtypes desmoplastic and acantholytic are often biologically aggressive squamous cell carcinomas. Tumor diameter > 2 cm is the risk factor most highly associated with disease specific death. Perineural involvement of nerves > 0.1 mm is associated with increased nodal metastasis and increased mortality risk.
The AJCC most recent staging system, published October 2016, uses tumor diameter > 2 cm as the distinguishing factors between T1 and T2 tumors. Other high risk factors in the AJCC-8 staging system which upstage tumors to T3 include diametere >4cm, minor bone erosion, invasion of nerves >0.1 mm, or deep invasion below the subcutaneous fat. T4 is reserved for major bone involveent under this staging system. Alternatively, the Brigham and Women’s Hospital (BWH) staging systems contains a high risk T2b category requiring 2 or more of the following risk factors: tumor diameter > 2 cm, poorly differentiated histology, perineural invasion >0.1 mm, or tumor invasion beyond fat (exlcluding bony invasion which automatically upstages tumor to T3).
Tumors greater than 2 cm are higher risk. Verrucous carcinoma is a well-differentiated subtype of SCC with low metastatic potential. Anatomic location and immunosuppression host factors, while
important, do not portend as high a risk of nodal and metastatic potential as tumor characteristics in the AJCC/BWH staging systems.
15- Which tattoo pigment is the most difficult to treat?
A. Titanium dioxide
B. Cobalt aluminate
C. Carbon
D. Iron oxide
E. Chromium oxide
Correct choice: A. Titanium dioxide
Explanation: Tattoo ink removal by laser light works using complementary colors/wavelengths on the color wheel. Pigment usually absorbs light emitted of the opposite color on the wheel. For example, green tattoo pigment is best removed using a red laser (694 nm) and conversely red pigment is best removed with a green laser (532 nm). White ink (titanium dioxide) is composed of many different colors and, as such, reflects the colors of most laser light instead of absorbing them. This property makes white tattoos difficult to treat by most commercially available lasers.
The remainder of the answer choices are commonly treated with an appropriately selected laser wavelength.
Reference: Ho SG, Goh CL. Laser tattoo removal: a clinical update. J Cutan Aesthet Surg. 2015 Jan-Mar;8(1):9-15. PMID: 25949017
16- Which of the following is responsible for the sensory innervation of the majority of the dorsal foot?
A. Sural nerve
B. Superficial peroneal nerve
C. Deep peroneal nerve
D. Common peroneal nerve
E. Saphenous nerve
Correct choice: B. Superficial peroneal nerve
Explanation: The superficial peroneal nerve (superficial fibular nerve) is a mixed nerve that carries sensory information from the anterolateral aspect of the leg and the greater part of the dorsum of the foot (except for the first web space, which is innervated by the deep peroneal nerve). Entrapment of the superficial peroneal nerve is not uncommon and can present with pain in the sensory distribution of the nerve with or without paresthesia. The other remaining nerves are not responsible for the sensory innervation of the majority of the dorsal foot.
17- Which of the following peels is the best option for treatment of this condition?
A. Trichloroacetic acid 10-25%
B. Baker Gordon Peel
C. Three coats of Tricholoracetic acid 35%
D. Trichloroacetic acid 50%
E. Tricholoracetic acid 35% + jessner’s solution
Correct choice: A. Trichloroacetic acid 10-25%
Explanation: Indications for superficial chemical peels include melasma (shown in picture). This patient has darker skin. Superficial chemical peels can be used in all Fitzpatrick skin types. Tricholoracetic acid (TCA) 10-25%, Jessner’s solution, and Glycolic acid 20-70% are the best three superficial peel options for treatment of melasma. Baker Gordon Peel is a deep chemical peel, not for use in darker skin types. TCA 35% is a medium depth peel. One coat (not 3 coats) can be considered a superficial peel. Medium depth peels have a higher risk for postinflammatory hyperpigmentation in darker skin types. TCA 50% and TCA 35% + Jessner’s solution are medium depth peels.
18- Which of the following injectable fillers is most likely to produce a lip nodule?
A. Poly-L-lactic acid
B. Human collagen
C. Hyaluronic acid
D. Human fibroblasts
E. Calcium hydroxyl-apatite
c
Correct choice: E. Calcium hydroxyl-apatite
Explanation: Of the answer choices, calcium hydroxyl-apatite (Radiesse) is most likely to produce lip nodules and is thus viewed as contraindicated for lip injections.
The remaining answers are less likely to produce lip nodules.
- A- patient had sclerotherapy 90 minutes ago. She develops flushing, palpitations, sweating, and vomiting. Which sclerosant was used?
A. hypertonic saline
B. polidocanol
C. glycerine
D. sodium tetradecyl sulfate
E. sodium morrhuate
Correct choice: B. polidocanol
Explanation: Polidocanol can cause disulfiram like reactions. 1 mL of polidocanol contains 40.5 mg of ethanol, and patients taking disulfiram (Antabuse) should be warned about a possible alcohol– disulfiram reaction.
20- While performing Mohs micrographic surgery for this squamous cell carcinoma (shown in picture), you sever a nerve that lies superficially in the temple, just beneath the thin dermis and subcutaneous fat. The patient would have trouble performing which of the following?
A. Raising his eyebrows
B. Grimacing
C. Smiling
D. Closing his eyes
E. Chewing food
Correct choice: A. Raising his eyebrows
Explanation: Temporal nerve injury may cause permanent paralysis of the ipsilateral frontalis muscle, causing loss of horizontal forehead rhytides and descent of the brow on the affected side. The temporal branch of the facial nerve courses between the superficial and deep temporalis fascia, penetrating the underside of the frontalis muscle from its lateral edges. It lies in the subcutaneous fat overlying the SMAS of the temple and lateral forehead region. The greatest potential for nerve damage lies in the lateral regions of the face. In 15% of patients, there is a cross-innervation to the frontalis muscle by the more inferior zygomatic branch of the facial nerve. In the other 85% of patients, violating the temporal nerve results in motor denervation and the inability to raise a “droopy” eyebrow. Flattening of the forehead with diminished visibility of wrinkles and skin tension lines on the ipsilateral side is easily noticed. Over time, the inability to raise the eyebrow can lead to eyebrow and lid ptosis and upper visual field compromise as muscular disuse atrophy progresses.
B – The marginal mandibular branch of the facial nerve innervates the lip depressors. Injury can cause asymmetry when smiling or grimacing. C – The marginal mandibular branch of the facial nerve innervates the lip depressors. Injury can cause asymmetry when smiling or grimacing. D – The zygomatic branch of the facial nerve innervates the orbicularis oculi muscles. An injury can lead to inability to completely appose the upper and lower eyelids and subsequent corneal desiccation. E - The marginal mandibular branch of the facial nerve innervates the lip depressors. Injury can cause a compromise in mouth function, resulting in drooling.
21- These lesions have been present since birth. A laser with which wavelength is the treatment of choice?
A. 488nm
B. 510nm
C. 585nm
D. 755nm
E. 1320nm
Correct choice: C. 585nm
Explanation: The image depicts a capillary malformation (post-wine stain), which is most effectively treated by the pulsed dye laser (PDL) which has a wavelength setting of 585-595nm as this targets hemoglobin as its chromophore. Laser wavelengths of 488nm, 510nm, and 755nm taget melanin as the chromophore. Water is the chromophore for a laser operating at a wavelength of 1320nm.
22- According to the guidelines of the American Society for Dermatologic Surgery, the recommended maximal safe dosage of tumescent lidocaine totally by local anesthesia for a 110-kg female undergoing liposuction is approximately:
A. 4,950-6050 mg
B. 3,850-4,900 mg
C. 2,750-3,800 mg
D. 770 mg
E. 550 mg
Correct choice: A. 4,950-6050 mg
Explanation: Years of worldwide experience have shown that 55 mg/kg tumescent lidocaine for liposuction is remarkably safe. This dosage is safe most of the time. Multiple large surveys involving thousands of procedures have found no evidence of tumescent lidocaine toxicity at recommended dosage.
- A- 22 year old male patient is developing early androgenetic alopecia. He is seen for hair transplant consultation. How should you counsel this patient?
A. He can be scheduled for hair transplantation since he is over age 21
B. Patients younger than 25 are not preferred for hair transplantation
C. Finasteride can help because 5 alpha reductase activity is lower in areas of balding
D. Transplanted hairs are not permanent and hair loss will continue in the transplanted hairs as well
E. Patients with scarring alopecia cannot receive hair transplantation
Correct choice: B. Patients younger than 25 are not preferred for hair transplantation
Explanation: Patients younger than 25 are not recommended for hair transplantation. 5 alpha reductase activity is higher in areas of balding. Finasteride inhibits 5 alpha reductase type II and reverses miniaturization of hair follicles. Transplanted hairs are permanent as are the hairlines they create, which should be kept in mind at transplantation. Patients with scarring alopecia may benefit from hair transplant. However, they should have no evidence of inflammation for 6 months before the transplantation.
24-A patient had sclerotherapy and reports the injection was painful. Afterwards, she developed an ulcer over the injection site at the foot and ankle. Which sclerosant was most likely used?
A. hypertonic saline
B. polidocanol
C. glycerin
D. sodium tetradecyl sulfate
E. sodium morrhuate
Correct choice: A. hypertonic saline
Explanation: Hypertonic saline has the highest risk of cutaneous necrosis. The disadvantage of hypertonic saline is pain associated with injections and ulcerogenic potential. Often, anesthetic agents such as lidocaine are added to the mixture to minimize the discomfort involved, by decreasing the concentration of the saline and through the direct anesthetic effect. Hypertonic saline (10%) mixed with dextrose (25%) is another hyperosmolar agent that has been used in vein sclerosing. This agent has the advantages of low allergenicity and decreased pain compared with higher concentrations of plain hypertonic saline. However, this mixture is currently not FDA approved and is a relatively weak sclerosant compared to other options available. Ulceration can also occur with non-foamed sodium tetradecyl sulfate that is more than 1% in concentration.
25- What is the tissue temperature is required for destruction of basal or squamous cell carcinomas with cryotherapy?
A. -5° C
B. -15° C
C. -25° C
D. -35° C
E. -50° C
c
Correct choice: E. -50° C
Explanation: The temperature required for destruction of basal or squamous cell carcinoma is -50 degrees C. For melanocyte necrosis, -5 degrees C is required, and for keratinocyte treatment, -25 degrees C.
c
26- The pictured lesion will be best treated by a laser with which wavelength?
A. 1450nm.
B. 755nm
C. 694nm
D. 585nm
E. 510nm
Correct choice: D. 585nm
Explanation: The pictured lesion is a cherry angioma, which is a vascular lesion. Thus, it should be treated by a laser with a wavelength targeting hemoglobin as a chromophore. The Pulsed dye laser set at a 585nm wavelength is the best option listed.
The remaining answer choices do not target hemoglobin as a chromophore, so they would not be the best option in treating this cherry angioma:
1450nm-Diode laser (target chromophore: water) 755nm-Alexandrite laser (target chromophore: melanin) 694nm-Ruby laser (target chromophore: melanin)
510nm-short wavelength Pulsed dye laser (target chromophore: melanin)
27- Which of the following medications has demonstrated efficacy in the treatment of dermatofibrosarcoma protuberans (DFSP)?
A. Dabrafenib
B. Ipilimumab
C. Gefitinib
D. Erlotinib
E. Imatinib
Correct choice: E. Imatinib
Explanation: DFSP is a malignant neoplasm that most commonly presents as a slow-growing large nodule or plaque with multiple protuberances on the trunk of middle-aged adults. It is most often due to a reciprocal translocation of t(17;22)(q22;q13) resulting in fusion of collagen 1-alpha-1 and platelet-derived growth factor B (COL1A1-PDGFB) which serves as an oncogene. This is the basis of treatment with imatinib, a PDGF inhibitor.
Dabrafenib, a BRAF inhibitor, and Ipilimumab, a CTLA-4 inhibitor, are used in the treatment of metastatic melanoma. Gefitinib and Erlotinib are EGFR inhibitors that do not have efficacy in the treatment of DFSP.
28- True statements regarding skin cancer in organ transplant recipients include all of the following except:
A. 65 fold increase in development of SCC compared with general population
B. Kidney transplant patients are at the highest risk of developing cutaneous malignancies
C. Cutaneous malignancies develop 3-5 years after organ transplantation
D. Extent of tumor development related to degree of immunosuppression
E. Skin cancer is the most common cancer in transplant patients
Correct choice: B. Kidney transplant patients are at the highest risk of developing cutaneous malignancies
Explanation: Heart transplant patients are at the highest risk of cutaneous malignancies due to the extent of immunosuppresion they get.All the other answer choices represent true statements.
29- You have excised a large lipoma from a patient’s back, and would like to use an absorbable suture with the greatest tensile strength that lasts the longest. You look in your surgical supply closet, and choose which of the following:
A. Polydioxanone
B. Polyglactin 910
C. Poliglecaprone 25
D. Polyglycolic acid
E. Polypropylene
Correct choice: A. Polydioxanone
Explanation: Polydioxanone (PDS) is a polymer of paradioxanone. It is a monofilament, absorbable suture with 180 d absorption and low reactivity. The tensile strength is the greatest, and it lasts the
longest. The tensile strenght of PDS is 50% at 30 days. Polypropylene is not an absorbable suture and the other listed absorbale sutures do not have as a high a tensile strength as PDS. The tensile strenght of polyglactin is 50% at 21 days. The tensile strenght of polyglycolic acid is 20% at 21 days. The tensile strenght of Poliglecaprone 25 is 50% at 7 days.
30- This patient presented for a different lesion but you see this during your exam and perform a biopsy. If the pigmented lesion seen here is 0.9mm deep, what is the recommended margin for excision?
A. <0.5cm
B. 0.5cm
C. 1.0cm
D. 2.0cm
E. >2.0cm
Correct choice: C. 1.0cm
Explanation: The recommendation for a margin excision for in situ melanomas is 0.5cm (not including lentigo maligna forms).
Margin excision for a melanoma up to 1mm in thickness is 1.0cm. Thickness between 1.01-2mm requires a 1-2cm surgical margin, and >2cm is needed when the tumor thickness reaches 2mm.
The recommendation for a margin excision for in situ melanomas is 0.5cm (not including lentigo maligna forms). Margin excision for a melanoma up to 1mm in thickness is 1.0cm. Thickness between 1.01-2mm requires a 1-2cm surgical margin, and >2cm is needed when the tumor thickness reaches 2mm.
31- The nasolabial two stage flap depends on which artery for flap survival:
A. Supratrochlear artery
B. Superior labial artery
C. Angular artery
D. Lateral Nasal artery
E. Inferior labial artery
Correct choice: C. Angular artery
Explanation: Angular artery provides blood supply for the nasolabial transposition flap.
c
32- Which of the following statements best explains the principal of collimation with respect to lasers?
A. Emission of a well-defined wavelength (rather than a band of wavelengths)
B. Light waves traveling in phase, both in time and space
C. The parallel nature of a beam of light
D. Light that is amplified traveling back and forth between the laser’s mirrors
E. Perpendicular beams of light that increase scatter
Correct choice: C. The parallel nature of a beam of light
Explanation: Collimation refers to the parallel nature of light beams that make a laser focused on even small spot sizes. Monochromicity refers to a single wavelength, coherence refers to light traveling in phase. Light that is amplified traveling back and forth between the laser’s mirrors is how lasers operate. Perpendicular beams of light that increase scatter are not related to collimation.
- A- 63-year-old woman is seen for consultation for treatment of varicose veins in her bilateral legs. When discussing risks and benefits for treatment, you review the risks of having a rare anaphylactic reaction. Which of the following sclerosing agents has the highest risk for anaphylaxis?
A. Glycerin
B. Polidocanol
C. Sodium morrhuate
D. Hypertonic saline
E. Sodium tetradecyl sulfate
Correct choice: C. Sodium morrhuate
Explanation: The highest risk of anaphylaxis is with sodium morrhuate (Choice 3). Other side effects include pain, skin necrosis, and hyperpigmentation.
Glycerin (Choice 1) and hypertonic saline (Choice 4) alone do not carry any risk of anaphylaxis. There is a very rare risk of anaphylaxis with polidocanol (Choice 2) and sodium tetradecyl sulfate (Choice 5).
34- According to the information provided, the glasses shown provide protection for which laser type?
A. Pulsed dye 585 nm
B. Alexandrite 755 nm
C. Nd:YAG 1064 nm
D. Ruby 694 nm
E. Nd:YAG 650 nm
Correct choice: C. Nd:YAG 1064 nm
Explanation: Nd:YAG 1064nm. The ranges provided by the laser glasses indicate the wavelenghts the glasses protect for. It is important to note a crystal, such as Nd:YAG may produce more than one wavelenght.
Reference: Reference: Robinson. Surgery of the Skin. 2nd Ed. Chapter 33.
35- This patient underwent Mohs surgery with a bilobed transposition flap repair. The patient presents for a 2 month follow-up with the following result (indicated by the arrow). What is a common cause of this phenomenon?
A. Hematoma
B. Post-operative infection
C. Flap necrosis
D. Inadequate undermining
E. Undersizing of the flap
Correct choice: D. Inadequate undermining
Explanation: The arrow is pointing to an area of a trapdoor deformity which presents as pincushioning or a protuberant appearance of a flap. Commonly it presents 3-6 weeks post-op and is very common on the nose. It is likely due to circumferential contraction of the flap causing the flap to buckle. Ways to reduce this outcome is to undermine extensively under the entire flap and surrounding edges, properly size a flap (no oversize it or “stuff” it), square the edges of the flap as U-shaped flaps are more likely to buckle, and thin the flap appropriately.
Oversizing the flap rather than undersizing can lead to trapdoor/pin-cushioning. Hematoma, post-op infection and flap necrosis can all lead to poor outcomes of healing but not as likely to cause trapdoor deformity.
36- In the 60-degree z-plasty technique, the length of the scar length is increased by what percentage?
A. 25%
B. 35%
C. 50%
D. 75%
E. 90%
Correct choice: D. 75%
Explanation: A Z-plasty is a transposition flap used to treat wound contractures and scars. It is performed to decrease tension on a wound, change the orientation of a scar, and improve overall scar appearance. A 60-degree Z-plasty will yield a 75% increase in scar length and a 90-degree change in scar direction. A 45-degree Z-plasty will yield a 50% increase in scar length, and a 30- degree Z-plasty will yield a 25% increase in scar length.
37- What is the most appropriate choice for treating a basal cell carcinoma 6 mm in size at this location in a 48 year old patient who is otherwise healthy and who has only made one skin cancer to date?
A. Mohs micrographic surgery with repair
B. Radiation
C. Electrodessication and curettage
D. Excision with repair
E. Cryotherapy and curettage
Correct choice: A. Mohs micrographic surgery with repair
Explanation: Mohs micrographic surgery is the correct choice for the patient presented who has a 6 mm basal cell carcinoma located on the nasolabial fold in the region of the apical triangle. While the patient may elect not to proceed with therapy or choose a therapy with a lower cure rate compared to Mohs micrographic surgery, the most appropriate treatment option should be encouraged. Excision would offer the second highest cure rate for a 6 mm basal cell carcinoma at the apical triangle of the face, but is sub-optimal to Mohs micrographic surgery. Radiation should not be used for this basal cell carcinoma that can otherwise be surgically approached.
Electrodessication and curettage and cryotherapy and curettage do not offer appropriate cure rates for a basal cell carcinoma on the face of our patient.
38- Which of the following absorbable sutures has the highest tissue reactivity?
A. Chromic gut
B. Plain gut
C. Polyglycolic acid
D. Polydioxanone
E. Poliglecaprone
Correct choice: B. Plain gut
Explanation: Plain gut has the highest tissue reactivity amongst absorbable sutures. Chromic gut has high tissue reactivity, but it is less so than plain gut. The other answer choices have low tissue reactivity.
39- What structure is being lifted by the dissecting probe?
A. Angular artery
B. Transverse facial artery
C. Buccal nerve
D. Mental nerve
E. Superior labial artery
Correct choice: A. Angular artery
Explanation: The identified structure is the angular artery. After forming the superior labial branch, the facial artery becomes known as the angular artery.The pictured structure is wider caliber vessel, thus not a nerve. The superior labial artery and the transverse facial artery have lateral-medial orientations as opposed to the caudal-cephalad orientation of the angular artery/facial artery.
40- What is the best choice of a wavelength of a laser to treat the changes you see here?
A. 595 nm
B. 1,064 nm
C. 810 nm
D. 755 nm
E. 10,600 nm
Correct choice: E. 10,600 nm
Explanation: CO2 resurfacing and ablative lasers (10,600 nm) are the best for severe rhinophyma as is seen here. The other wavelengths represent lasers that will be less effective in treating the disease at this late stage.
41- Fast absorbing gut sutures are broken down in the skin by which process?
A. Hydrolysis
B. Proteolysis
C. Acetylcholinesterases
D. Cytochrome p-450
E. They are not broken down, and must be physically removed.
Correct choice: B. Proteolysis
Explanation: Fast absorbing gut is made up of a natural fiber. Natural fibers include those that are absorblable such as surgical gut, and those that are nonabsorbable such as silk. Absorbable natural sutures are broken down by proteolysis. Synthetic absorbable sutures are broken down by hydrolysis.
42- For a graft to be successful, what are the following stages it must go through (in order and according to approximate time intervals)?
A. Neovascularization, maturation, inosculation, imbibition
B. Imbibition, inosculation, neovascularization, maturation
C. Inosculation, imbibition, maturation, neovascularization
D. Imbibition, neovascularization, inosculation, maturation
E. Inosculation, neovascularization, imbibition, maturation
Correct choice: B. Imbibition, inosculation, neovascularization, maturation
Explanation: All successful grafts go through the following stages: 1. Imbibition – for the first 48 hours the graft is sustained by plasma from the recipient bed, hyperemia 1-3 days 2. Inosculation – on day 2-3 blood vessels in the graft establish connections with the wound bed 3. Neovascularization – ingrowth of new vessels into the graft occurs at approximately one week 4. Maturation – months post-grafting, sensory innervation occurs and the graft becomes paler
Reference: Reference: Dermatology In-Review. 2016-2017 ed. p512.
43- The instument number 3 is what?
A. Iris scissor
B. Mayo scissor
C. Gradel scissor
D. Suture scissor
E. Straight Metzenbaum scissor
Correct choice: A. Iris scissor
Explanation: Iris scissor. They have two sharp points and used for tissue dissection. Reference: Reference: Robinson. Surgery of the Skin. 2nd ed. Ch. 4
44- Post-operatively, one of your surgical patients notices numbness of the inferior two-thirds of the ear. Which nerve may have been injured?
A. Great auricular nerve
B. Lesser occipital nerve
C. Auriculotemporal nerve
D. Facial nerve
E. Glossopharyngeal nerve
Correct choice: A. Great auricular nerve
Explanation: The great auricular nerve(C2, C3) exits approximately 6.5 cm below the external auditory canal along the posterior border of the sternocleidomastoid muscle and extends superiorly. Injury leads to numbness of the inferior two-thirds of the ear and the adjacent cheek and neck.
45- This patient underwent Mohs surgery and presents for suture removal. The following photo is an example of which type of closure?
A. Split-thickness skin graft
B. Full-thickness skin graft
C. Composite graft
D. Transposition flap
E. Interpolation flap
Correct choice: B. Full-thickness skin graft
Explanation: This is an example of a full thickness skin graft. There is a circular graft on the ear, and a linear scar on the preauricular cheek indicating this as the donor site. Donor sites are commonly taken from the pre or post-auricular skin as it is easy to hide the scar in those locations. A split thickness graft is composed of epidermis and some dermis and is very thin. The donor site is usually left to heal by secondary intent and taken from a site that is easy to conceal, therefore there would not be a linear scar on the preauricular cheek. A composite graft typically includes 2 tissue types such as cartilage and skin. Although composite grafts can be use to repair ears to rebuild the structure/foundation, it would require cartilage to be taken from a donor site on the nose or ear, and the photo does not show any donor sites that would indicate this. In addition a very small defect, such as the one shown in this image, would likely not require cartilage. An interpolation or transposition flap would not have a linear scar at the preauricular cheek.
46- Six weeks following surgery, a scar is at which strength?
A. 5%
B. 15%
C. 40%
D. 70%
E. 80%
Correct choice: C. 40%
Explanation: A scar’s strength at 6 weeks is 40%. Scar strengths based on timeframe:
2 weeks- 5%
3 weeks- 15%
6 weeks- 40%
6 months- 70%
1 year- 80% (maximum strength of scar compared to original strength prior to injury/surgery)
47- Pigmentation defects represent abnormalities limited to the color of the skin and are frequently encountered in practice arising from inflammatory conditions, systemic disorders, or extrinsic effects such as sun exposure or treatment with dialysis. A patient presents to you with yellowish skin from undergoing hemodialysis for renal failure as well as underlying solar elastosis. The yellowish discoloration resulting from solar elastosis and treatment with chronic dialysis can be camouflaged by applying which of the following complementary-colored opaque cosmetic foundations?
A. Green
B. Purple
C. Brown
D. White
E. Yellow
Correct choice: B. Purple
Explanation: Pigmentation defects or discolorations can be camouflaged either by applying an opaque cosmetic that allows none of the abnormal underlying skin tones to be appreciated or by applying foundations of complementary colors. For example, red discoloration can be camouflaged by applying a green foundation, since green is the complementary color to red. The blending of the red skin with the green foundation yields a brown tone, which can be readily covered by a more conventional facial foundation. Furthermore, yellow skin tones can be blended with a complementary-colored purple foundation to also yield brown tones.
1 - Green: Red discoloration can be camouflaged by applying a green foundation, since green is the complementary color to red.
3 - Brown: Brown hyperpigmentation from skin conditions such as melasma, lentigines, and nevi can be camouflaged by using a white undercover foundation color.
4 - White: Hypopigmentation and depigmentation from skin conditions such as postinflammatory hypopigmentation, congenital pigmentary disorders and vitiligo can be cmouflaged by using a brown undercover foundation color.
5 - Yellow: Yellow facial color from conditions such as solar elastosis, chemotherapy and dialysis can be camouflaged by applying a purple undercover foundation color.
- A- patient undergoes Mohs surgery with a full-thickness skin graft repair. A bolster dressing was then sewn on over the graft. The bolster dressing would aim to promote healing of the graft during which phase?
A. Imbibition
B. Inosculation
C. Neovascularization
D. Maturation
E. Delayed phase
Correct choice: A. Imbibition
Explanation: Imbibition is the first stage of healing for skin grafts. It takes place during the first 48 hours where the graft is recieving nutrients by passive diffusion from the underlying wound bed. It is imperative that there is good connection/adherence of the flap with the wound bed for this to occur. This can be acheived with basting (tacking or quilting) sutures and a bolster. The bolster also provides stability and protection from trauma to the delicate graft.
Inosculation occurs after 2-3 days later, where the blood vessels in the graft start to establish connections to the underlying wound bed.
Neovascularization is the growth of new vessels into the graft between 4-7 days. Maturation or Reinvervation occurs months after the graft is placed where sensory innervation develops and the graft becomes paler. Delayed phase is not a known healing phase for grafts.
49-Which of the following is true regarding iodophor (Betadine) as an antiseptic?
A. Gram + coverage only
B. Gram - coverage only
C. Flamable
D. Ototoxic
E. Inactivated by blood
Correct choice: E. Inactivated by blood
Explanation: Iodophor (Betadine) is an antiseptic in the halogen class with moderate onset of activity that is sustained up to 1 hour. Spectrum includes gram+ and gram- organisms. It is absorbed through skin, must be dry to be effective, is tissue damaging, and inactivated by blood. It sometimes causes an allergic contact dermatitis.
- A- shave biopsy is performed on the helix and electrosurgery is used for hemostasis. Which form of electrosurgery is shown in the image, in which the electrode is spaced a few millimeters from the defect?
A. Electrocautery
B. Electrocoagulation
C. Electrodessication
D. Electrosection
E. Electrofulguration
Correct choice: E. Electrofulguration
Explanation: The correct answer is electrofulguration (Choice 5), in which there is superficial ablation where the tip of probe does not contact the skin. This method allows an electric spark to jump to the skin causing superficial epidermal carbonization, protecting the underlying tissue from heat. Choice 1 is incorrect as electrocautery is not true electrosurgery because there is no current running through the patient. Instead, electrocautery uses heat to achieve hemostasis. Electrocoagulation (Choice 2), electrodessication (Choice 3), electrosection (choice 4) involve the probe being in direct contact with the tissue.
51- The patient declines surgical intervention for this cutaneous neoplasm and a decision is made to pursue medical therapy. What is the most common side effect of the FDA-approved medication for this neoplasm
A. Nausea
B. Flu-like illness
C. Chest pain
D. Muscle spasms
E. Alopecia
Correct choice: D. Muscle spasms
Explanation: Vismodegib is smoothened (SMO) inhibitor approved for the treatment of adults with basal cell nevus syndrome, metastatic or locally advanced BCC that has recurred following surgery or who are not candidates for surgery or radiation. The most commonly reported side effect is muscle spasm, followed by alopecia and dysgeusia.
52- Which of the following sites would be appropriate for secondary intention healing?
A. Medial canthus
B. Alar crease
C. Conchal bowl
D. Lower eyelid
E. A, B, & C
Correct choice: E. A, B, & C
Explanation: Secondary intention healing occurs when the wound is allowed to heal on its own. This process allows for healing primarily by the contraction of myofibroblasts. It may be an excellent alternative for select defects, ie. surgical defects on concave areas, such as the medial canthus, alar crease, temple (as long as the defect is not too close to a free margin or anatomical landmark), and conchal bowl (as long as defect does not approach the external auditory meatus).
The remaining answer choices are incorrect.
53- Which of the following wound care dressings is the most appropriate choice for a dry, painful wound?
A. Foams
B. Hydrogels
C. Hydrofilms
D. Hydrocolloids
E. Alginates
Correct choice: B. Hydrogels
Explanation: Hydrogels are good for dry painful wounds. Foams are absorptive. Hydrofilms are occlusive, allowing gas and water vapor to permeate. Hydrocolloids are fibrinolytic, cause angiogenesis, inhibit keratinocyte migration, antibacterial increases healing rate, can cause surrounding maceration. Alginates are the most absorptive and are turned into gel by the wound exudate.
54- Which of the following is the most effective topical treatment option for pulsed dye laser- induced purpura?
A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin E
E. Vitamin K
Correct choice: E. Vitamin K
Explanation: Vitamin K oxide gel appears to hasten the resolution of pulsed dye laser- induced purpura in subjects being treated for bilateral facial telangiectasia, and may well be useful in accelerating resolution of facial bruising from other cosmetic procedures such as fillers used for soft-tissue augmentation as well as other types of cutaneous surgical procedures.
55- All of the following are major antioxidants in the human epidermis except?
A. Superoxide dismutase
B. Coenzyme Q10
C. L-Ascorbate
D. Cathelicidin
E. Alpha-tocopherol
Correct choice: D. Cathelicidin
Explanation: Cathelicidin is an anti-microbial peptide in human epidermis thought to be upregulated in conditions such as psoriasis and rosacea. The remainder of the answers are all antioxidants which are naturally found in the skin. Research into the preventive role of topical antioxidants in photoaging is based on the free radical theory of aging. Epidermal depletion of these substances has been shown to be an early and sensitive marker of environmental oxidative damage.
- A patient comes in for endovenous laser ablation for varicose veins. Which type of anesthesia should be used?
A. general anesthesia
B. tumescent anesthesia
C. 1% lidocaine without epinephrine
D. 0.05% marcaine with epinephrine
E. 1% sodium tetradecyl sulfate
Correct choice: B. tumescent anesthesia
Explanation: Tumescent anesthesia is used for endovenous radiofrequency ablation and endovenous laser ablation. This allows separation of the vessel from the surrounding tissue, thereby protecting surrounding tissue (including nerves) from injury. Endovenous ablation procedures can be done in an outpatient setting, without general anesthesia. 1% sodium tetradecyl sulfate is a sclerosant, not an anesthetic.
57-Which of the following best describes a tip stitch?
A. Half-buried horizontal mattress suture
B. Modified vertical mattress suture
C. Running horizontal mattress suture
D. Buried vertical mattress suture
E. Purse-string suture
Correct choice: A. Half-buried horizontal mattress suture
Explanation: A tip stitch is a half-buried horizontal mattress suture. It is most commonly used to align tissue and secure the tips of flaps. A pulley suture is a modified vertical mattress suture and is used for areas of high tension. The other options are incorrect.
- A- patient is scheduled for an excision on the pretibial area. Choose the most appropriate dermal suture for this site:
A. Polydioxanone
B. Poliglecaprone 25
C. Chromic gut
D. Polyester
E. Glycomer 631
Correct choice: A. Polydioxanone
Explanation: Polydioxanone (PDS) is an absorbable suture that lasts 180 days and is good for high tension areas such as the leg. Monofilament sutures such as poliglecaprone 25 and glycomer 631 work, but not as well in terms of duration of tensile strength for high tension areas.
59-A 62 year-old man presented for Mohs surgery for a basal cell carcinoma at his right posterior ear. The tumor was cleared after 2 stages, and was repaired as seen in the photo. What is the first phase of full thickness graft healing?
A. Imbibition
B. Inosculation
C. Neovascularization
D. Epithelial proliferation
E. Maturation
Correct choice: A. Imbibition
Explanation: A full thickness skin graft was used here to repair the post-surgical defect. A full thickness skin graft consists of the entire epidermis and dermis, the subcutaneous tissue removed prior to inset to avoid graft compromise. All successful grafts go through the following stages: imbibition (first 48 hours), inosculation (day 2-3), neovascularization (~1 week), and maturation (months post-grafting).
60-A 65-year-old man presented for Mohs micrographic surgery of a basal cell carcinoma at his left posterior ear. You inject local anesthetic in a ring block fashion to provide adequate anesthesia for the surgical procedure. At which anatomic location of the ear will cutaneous sensation remain intact?
A. Auricle
B. Helix
C. Conchal bowl
D. Tragus
E. Antihelix
Correct choice: C. Conchal bowl
Explanation: A ring block around the ear anesthetizes the entire ear, except for the conchal bowl and external auditory meatus. The vagus nerve provides the cutaneous sensation for the conchal bowl.
The great auricular nerve innervates the majority of the posterior ear, as well as 3/4 of the anterior helix. The auriculotemporal nerve innervates the tragus, anterior helix and part of the superior helix.
61-A surgical patient calls you post-operatively, after noticing that he can no longer abduct his arm after his Mohs procedure today. Which nerve may have been injured in this case?
A. C2 and C3
B. Supraclavicular nerve
C. CN XI
D. CN VII
E. CN IX
Correct choice: C. CN XI
Explanation: Injury of the spinal accessory nerve results in the inability to elevate the shoulder on the affected side, winged scapula, and the inability to initiate arm abduction.
62- The laser glasses shown in this photo have the letters “O.D.” printed on them. What does O.D. stand for?
A. A logarithmic measure of the power transmission factor
B. The appropriate wavelength of light for these glasses
C. The antireflection coating to suppress unwanted reflections
D. The appropriate beam diameter for these glasses
E. A measure of light as waves with fixed phases in both time and space
Correct choice: A. A logarithmic measure of the power transmission factor
Explanation: The O.D. stands for optical density, identifying the amount of the medium that may penetrate a protection filter. This is a logarithmic measure: for example, O.D. of 4 means that the optical power is attenuated by the factor 10 to the power of 4= 10000 times. E is the definition of coherence. Reference: https://safety.vanderbilt.edu/laser/glossary-laser-terms.php https://www.rp- photonics.com/optical_density.html
63- An obese patient comes in for liposuction consultation and indicates several areas she would like treated on the abdomen, back, hips, and thighs. She thinks this will assist in weight loss and her appearance. How should you counsel this patient?”
A. Liposuction will help in weight reduction
B. There is no limit to the amount of fat that can be removed in a session
C. Moderate to severe obesity are contraindications to liposuction
D. Liposuction can help improve the cellulite along the hips, outer thighs, buttocks
E. Because of her size, the procedure will need to be done under general anesthesia
Correct choice: C. Moderate to severe obesity are contraindications to liposuction
Explanation: Liposuction is not intended for weight reduction. Moderate obesity is relative contraindication, while severe obesity is an absolute contraindication. The upper limit of fat extraction in one setting is 4500-5000mL, according to American Academy of Dermatology guidelines. Beyond this, fluid shifts can occur, resulting in cardiovascular compromise. Liposuction does not improve the appearance of cellulite. Tumescent anesthesia in the office for liposuction has a high safety profile. The serious complications seen in liposuction are associated with general anesthesia, not with procedures performed with local tumescent anesthesia. Although deaths have been reported during liposuction, none has occurred when patients were treated with tumescent anesthesia alone. Office-based tumescent liposuction performed by dermatologic surgeons is safe and has a lower complication rate than hospital-based procedures.
64- You diagnose a 0.35 mm Breslow depth melanoma on the right shoulder of a 62 year old male. What is the appropriate and necessary medical treatment?
A. Reassurance
B. Excision with 5 mm margin and sentinel lymph node biopsy
C. Radiation therapy
D. Excision with 10 mm margin
E. Excision with 15 mm margin and sentinel lymph node biopsy
c
Correct choice: D. Excision with 10 mm margin
Explanation: The correct approach is excision with 10 mm (1 cm) margin with repair.
5 mm and 15 mm are not the appropriate margins for excision of a 0.35 mm BD melanoma and sentinel lymph node biopsy is not indicated. Radiation therapy is not the appropriate treatment.
65- Which of the following is FALSE regarding Mohs micrographic surgery?
A. Most large studies show a complication rate of below 1% to 3%
B. No deaths have been reported as a complication of Mohs surgery
C. Infection rates have been shown to be unaffected by use of nonsterile vs sterile gloves
D. Wrong site surgery is the most common reason for legal claims against Mohs surgeons
E. With regard to biopsy site identification prior to surgery, photographic documentation does not improve accuracy compared to clinical notes and diagrams
Correct choice: E. With regard to biopsy site identification prior to surgery, photographic documentation does not improve accuracy compared to clinical notes and diagrams
Explanation: The correct answer is E (E is false). Photographic documentation has shown to improve biopsy site identification prior to Mohs surgery [ii. Hansen TJ, Lolis M, Goldberg DJ, MacFarlane DF. Patient safety in dermatologic surgery: Part I. Safety related to surgical procedures. J Am Acad Dermatol. 2015 Jul;73(1):1-12. ]
- A- 70 year-old woman presents for follow-up 1 week after Mohs micrographic surgery of a poorly differentiated squamous cell carcinoma at the left temple. She is noted to have flattening of the left forehead and inability to raise her left eyebrow. At which anatomic location did the suspected nerve injury occur?
A. 2 cm posterior to lateral oral commissure
B. At the lateral canthus
C. 3 cm above the left eyebrow
D. Between the lateral eyebrow and anterior hairline
E. Anterior hairline at mid-pupillary level
Correct choice: D. Between the lateral eyebrow and anterior hairline
Explanation: The temporal nerve runs 0.5cm below the tragus to 1.5cm above the lateral brow. The danger zone of the temporal branch of CN VII occurs within a 2 cm box from lateral eyebrow to anterior hairline where it runs beneath the SMAS. Injury to this nerve results in unilateral forehead paralysis, ipsilateral forehead flattening, and eyelid ptosis.
67-A patient is scheduled for liposuction on the hips, buttocks, knees, arms, and back. In which body part can compartment syndrome occur after liposuction?
A. hips
B. buttocks
C. knees
D. arms
E. back
Correct choice: D. arms
Explanation: Compartment syndrome can occur in the arms, distal to the area infused with tumescent anesthesia due to fluid compression. Avoid anterior flexural surfaces. Postliposuction edema can occur in the thighs and abdomen. For example, circumferential liposuction of the thigh can theoretically cause prolonged postoperative edema by precipitating a vicious cycle and temporarily obliterating a significant portion of lymphatic drainage from the lower limb. This liposuction-induced edema produces a mild compartment syndrome with local hematic capillary ischemia, decreasing delivery of oxygenated blood, augmenting anaerobic metabolism, and increasing capillary permeability. This increased capillary permeability produces still more edema.
68- Which of the following sutures absorbs most rapidly?
A. Chromic gut
B. Polyglycolic acid
C. Polyglactin 91
D. Polydioxanone
E. Plain gut
Correct choice: E. Plain gut
Explanation: Of the absorbable sutures listed, plain gut absorbs most rapidly (absorption complete in 60-70 days). Chromic gut completely absorbs in ~80 days. Polyglactin 910 (Vicryl) and polyglycolic acid (Dexon) are both absorbed in about 90 days. Polydioxanone (PDS) is an absorbable monofilament which takes approximately 180 days to completely absorb.
69- Which of the following tattoo pigments is most commonly associated with allergic reactions, both eczematous and granulomatous?
A. Mercuric sulfide
B. Titanium dioxide
C. Cadmium sulfide
D. Ferric oxide
E. Iron oxide
Correct choice: A. Mercuric sulfide
Explanation: Allergic reactions have been reported with several different types of tattoo pigment. The most commonly associated tattoo pigment, however, is mercuric sulfide. Tattoos with mercuric sulfide appear red in color. Titanium dioxide (white tattoo color), Cadmium sulfide (yellow tattoo color), Ferric oxide (brown tattoo color), and Iron oxide (black tattoo color) are less commonly associated with allergic reactions. Of note, Cadmium sulfide is the tattoo pigment most commonly associated with phototoxic reactions.
A- 60-year-old female undergoes a surgical excision of a lipoma with complex linear closure on the left forearm. Approximately 24 hours later, she shows up in your dermatology clinic concerned about the following skin lesions present in the picture. You instruct the patient to avoid adhesives. Which is the next best step in this patient’s management?
A. Apply topical triple antibiotic ointment
B. Perform patch testing
C. Treat with a high-potency topical steroid
D. Treat with a burst of oral corticosteroids
E. Treat with non-steroidal anti-inflammatory agents
Correct choice: C. Treat with a high-potency topical steroid
Explanation: Allergic contact dermatitis to triple-antibiotic ointment or tape is a common complication or pitfall after surgery. The initial appropriate steps are to withdraw the likely source of allergen and treat with high-potency topical steroids. In the future, patch testing may be an appropriate investigation to pursue. Administration of non-steroidal anti-inflammatories is not necessary and is not the best single answer choice.
71- Which of the following is the most common genetic alteration seen in mucosal melanomas?
A. GNAQ
B. Cyclin Dependant Kinase 4/6
C. BRAF
D. KIT
E. MDM2
Correct choice: D. KIT
Explanation: Mucosal melanomas tend to have an activating mutation in KIT.
GNAQ mutations are seen in both uveal melanomas and blue nevi. Cyclin dependant kinase 4/6 binds cyclin D and together phosphorylate Retinoblastoma. MDM2 targets p53 for ubiquitination.
72- Which of the following anatomic structures is most likely to be severed during this repair?
A. Mental nerve
B. Angular artery
C. Buccal nerve
D. Inferior labial artery
E. Marginal mandibular nerve
Correct choice: D. Inferior labial artery
Explanation: The photograph demonstrates a wedge resection which is used to repair defects of the lower lip. During this repair, the inferior labial artery is likely to be severed since it courses superficially between the mucosa and the underlying muscle.
The angular artery, mental nerve, buccal nerve, and marginal mandibular nerve are unlikely to be severed during a wedge resection of the lower lip.
- A- patient of skin type III presents for ablative CO2 resurfacing. Which of the following is true?
A. The patient will have reduced risk of hyperpigmentation if they begin hydroquinione 2 weeks prior to the procedure
B. If the patient develops post-inflammatory hyperpigmentation, then hydroquinone is effective in treatment
C. Antivirals should not be given prior to procedure as they have not demonstrated any benefit in reduction of herpes simplex reactivation
D. The patient should have completed isotretinoin at least 3 months prior to CO2 laser resurfacing
E. CO2 lasers are ineffective in resurfacing
Correct choice: B. If the patient develops post-inflammatory hyperpigmentation, then hydroquinone is effective in treatment
Explanation: Hydroquinone does reduce post-inflammatory hyperpigmentation if it does develop after laser resurfacing. The 1999 paper by West and Alster demonstrated that pretreatment with hydroquinone did not reduce the risk of hyperpigmentation after CO2 laser resurfacing. Antivirals
have been shown, when prophylactically given, to reduce HSV outbreaks before medium depth peels and resurfacing in those prone to outbreaks. Isotertinoin should be completed 6-12 months prior due to atrophy of pilosebaceous units, thus increasing scarring risk after ablative CO2 laser resurfacing.
74-What is the treatment of choice for dermatofibrosarcoma protuberans?
A. wide local excision
B. cryotherapy
C. imatinib
D. Mohs surgery
E. observation
Correct choice: D. Mohs surgery
Explanation: Mohs surgery. Mohs surgery is the treatment of choice for DFSP. The local recurrence rate is 1% with Mohs surgery (vs. 15-50% with wide local excision). Imatinib is approved for unresectable or metastatic disease and targets the COL1A1-PDGFB fusion protein.
- A- patient sees you in your office for a cosmetic consultation for submental fullness. When discussing indications and risks of injecting deoxycholic acid (Kybella) you inform her that there is a risk of marginal mandibular nerve injury. A marginal mandibular nerve injury would manifest with which of the following:
A. Difficulty swallowing on the affected side
B. Frequent salivation on the affected side
C. Inability to chew properly on the affected side
D. Inability to elevate and retract the lip on the affected side
E. Inability to depress and retract the lip on the affected side
Correct choice: E. Inability to depress and retract the lip on the affected side
Explanation: The marginal mandibular nerve innervates the depressor anguli oris, depressor labii inferioris, mentalis, orbicularis oris, risorius, and platysma muscles. Depression and retraction of the lip is controlled by depressor anguli oris, depressor labii inferioris, and mentalis muscles. An injury to the marginal mandibular nerve would thus cause an inability to smile, and interfere with depression and retraction of the lip on the affected side. The mouth would seem normal at rest, but crooked when attempting to smile.
1 – A marginal mandibular nerve injury does not present with difficulty swallowing. 2 – A marginal mandibular nerve injury does not present with frequent salivation on the injured side. 3 – The buccal nerve innervates the buccinators which help to prevent accumulation of food between teeth and buccal mucosa with chewing. 4 – The buccal nerve innervates the zygomaticus minor, levator labii superioris, and risorius which elevate and retract the lip.
76- Within which anatomic plane does the artery that was encountered during this repair lie?
A. Submucosal
B. Dermal
C. Intramuscular
D. Submuscular
E. There is no major artery in this surgical field
Correct choice: A. Submucosal
Explanation: The inferior labial artery is derived from the facial artery or superior labial artery, and runs through the submucosal tissue horizontally.
The inferior labial artery does not typically lie in the other listed anatomic planes.
77- Regarding the use of chlorhexidine, which of the following is true?
A. Chlorhexidine rinses (0.12%) aid in prevention of drug-associated gingival enlargment
B. Chlorhexidine, when applied to the eyes, will reduce keratitis
C. Chlorhexidine reduces risk of deafness when applied to the ear canal prior to surgery
D. Chlorhexidine leads to reduction of suture strength when applied to wounds
E. The efficacy of chlorhexidine is reduced when combined with isopropyl alcohol
Correct choice: A. Chlorhexidine rinses (0.12%) aid in prevention of drug-associated gingival enlargment
Explanation: Chlorhexidine rinses help prevent drug-associated gingival enlargement. Chlorhexidine is irritating to eyes and middle ear. It has no effect on suture strength. ChloraPrep is a combination of chlorhexidine and isopropyl alcohol.
Reference: Reference: Dermatology. Bolognia, Jorizzo, Schaffer. 3rd ed. Ch 72.
- A- male patient with androgenetic alopecia is seen for hair transplant consultation. He tried topical minoxidil and oral finasteride. You want to set realistic expectations for this patient. How should you counsel this patient?
A. Stop minoxidil and finasteride, he will no longer need it after hair transplant
B. Androgenetic alopecia progresses until age 50
C. Medical therapy is used in conjunction with hair transplant to maximize hair density
D. Additional hair transplants will not be needed in the future
E. The hairs grown or maintained by use of minoxidil and finasteride will stay in place once these medications are stopped
Correct choice: C. Medical therapy is used in conjunction with hair transplant to maximize hair density
Explanation: Medical therapy such as minoxidil and finasteride are often used in conjunction with hair transplantation to maximize density and minimize ongoing hair loss. Patients should be counseled that androgenetic alopecia (AGA) is an ongoing process. The progressive nature of AGA means that additional hair transplants may be required in 5-10 years. The physician should emphasize before the procedure how ongoing hair loss will affect the density and cosmetic appearance of the transplant. If medications are discontinued, the patient can expect loss of hairs grown or maintained by their use.
79- The patient had an extensive superficial basal cell carcinoma on the forehead treated with topical imiquimod and returned 4-weeks later with this reaction. Which cytokine is not activated by this medication?
A. tumor necrosis factor (TNF)-α
B. interferon (IFN)-α
C. interferon (IFN)-γ
D. interleukin (IL)-12
E. interleukin (IL)-4
Correct choice: E. interleukin (IL)-4
Explanation: Imiquimod is a topical immunomodulator that is FDA-approved for the treatment of genital warts, actinic keratosis and superficial basal cell carcinomas. It induces toll like receptor (TLR) 7 and the production of Th-1 cytokines including tumor necrosis factor (TNF)-α , interferon (IFN)-γ , interferon (IFN)-α , and interleukin (IL)-12, leading to stimulation of a cell-mediated immune response. IL-4, IL-5, IL-6 and IL-13 are Th-2 cytokines.
80- What is the name of the instrument “1”?
A. Bishop-Harmon forceps
B. Adson forceps
C. Kelly forceps
D. Castroviejo forceps
E. Jewelers forceps
Correct choice: A. Bishop-Harmon forceps
Explanation: Bishop-Harmon forceps
Reference: Reference: Dermatology. Bolognia, Jorizzo, Schaffer. 3rd ed. Ch 144.
- A- patient recently underwent parotid surgery and now reports unilateral flushing and sweating around mealtime. The nerve injured in this syndrome is a branch of which nerve?
A. Facial nerve
B. Maxillary nerve
C. Mandibular nerve
D. Cervical nerve
E. Frontal nerve
Correct choice: C. Mandibular nerve
Explanation: This patient has Frey syndrome or auriculotemporal nerve syndrome. This is characterized by facial flushing, sweating, or both localized to the distribution of the auriculotemporal nerve (a branch of the mandibular nerve) that occurs in response to gustatory stimuli. In adults, the syndrome usually results from surgical injury or trauma to the parotid gland.
82-A 75-year-old man is preparing for excision of the shown lesion on his trunk. His preoperative evaluation reveals that he has a pacemaker and also is known to have mitral valve prolapse without
valvular regurgitation. According to the American Heart Association, which of the following antibiotic dosing regimens is indicated prior to his surgery?
A. Amoxicillin, 2 g, 1 hour before the procedure
B. Amoxicillin, 1 g, 1 hour after the procedure
C. Azithromycin, 1 g, 1 hour before the procedure
D. Clindamycin, 500 mg, 1 hour after the procedure
E. No antibiotics
Correct choice: E. No antibiotics
Explanation: This patient does not require preoperative antibiotics.
The presence of implantable defibrillators and pacemakers are not indications for antibiotic use. Patients with mitral valve prolapse without valvular insufficiency or regurgitation noted on ultrasound are at no higher risk for bacterial endocarditis than the general population and, therefore, do not require preoperative antibiotics.
According to the AHA, those patients who are at high risk for bacterial endocarditis and require preoperative antibiotics include those with prosthetic cardiac valves, previous bacterial endocarditis, complex cyanotic congenital heart disease, and surgically constructed systemic-pulmonary shunts. Moderate risk patients include those with mitral valve prolapse with regurgitation, acquired valvular dysfunction, and hypertrophic cardiomyopathy
83-Which of the following suture materials induces the least inflammation?
A. Surgical gut
B. Polyglycolic acid (Dexon)
C. Polyglycan 910 (Vicryl)
D. Polypropylene (Prolene)
E. Silk
Correct choice: D. Polypropylene (Prolene)
Explanation: Prolene is a nonabsorbable suture material that evokes only minimal inflammation. Vicryl, Dexon, silk and surgical gut are associated with more inflammation than prolene.
A- Z-plasty represents which type of surgical reconstruction?
A. Complex linear layered closure
B. Advancement flap
C. Rotation flap
D. Transposition flap
E. Interpolation flap
Correct choice: D. Transposition flap
Explanation: A Z-plasty is a type of transposition flap that is useful for scars crossing relaxed tensions lines or releasing contractures (redistributes tension over wound).
A Z-plasty involves the movement of tissue via transpositioning across intervening islands of unaffected tissue. Therefore, the remaining answer choices are not correct.
85- Endocarditis prophylaxis is recommended for which of the following?
A. Rheumatic heart disease
B. Atrial septal defects
C. Hypertrophic cardiomyopathy
D. Mitral valve prolapse without regurgitation
E. Previous bacterial endocarditis
Correct choice: E. Previous bacterial endocarditis
Explanation: Preoperative antibiotics are recommended for endocarditits prophylaxis in select high risk patients that undergo high risk procedures. High risk procedures are procedures that involve manipulation of gingival tissue or the periapical region of teeth or perforation of the oral mucosa. High risk patients are, according to the guidelines, those with the following: Prior infective endocarditis, Prosthetic cardiac valves, Unrepaired cyanotic congenital heart defects, including palliative shunts and conduits, congenital heart defects completely repaired with prosthetic material or a device, whether placed by surgery or by catheter intervention, during the first 6 months after the procedure, repaired congenital defects with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device, cardiac transplants and development of cardiac valvulopathy. Patient groups that may have received routine antibiotic prophylaxis in the past but are no longer candidates for it include those with mitral and aortic valve disease, rheumatic heart disease, or structural disorders like ventricular or atrial septal defects or hypertrophic cardiomyopathy, according to the AHA statement. The revised guidelines were developed with the participation of and have been endorsed by the American Dental Association, the Infectious Diseases Society of America, and the American Academy of Pediatrics. Classically 1 gram of Dicloxacillin or cephalexin is given 1 hour preoperatively and an additional 500 mg is given 6 hours post op. Clindamycin can be givenin those patients who are penicillin allergic.
Patient groups that may have received routine antibiotic prophylaxis in the past but are no longer candidates for it include those with mitral and aortic valve disease, rheumatic heart disease, or structural disorders like ventricular or atrial septal defects or hypertrophic cardiomyopathy, according to the AHA statement.
86- What is the optimal time to take down this flap?
A. 3 weeks
B. 1 week
C. 2 weeks
D. 4 weeks
E. 3 days
correct choice: A. 3 weeks
Explanation: This is an interpolation flap and the optimal time for take down is 3 weeks after the flap is done.
87- What is the name of the pictured instrument?
A. Westcott scissors
B. Gradle scissors
C. Metzenbaum scissors
D. Adson scissors
E. Iris scissors
correct choice: B. Gradle scissors
Explanation: The pictured instrument is a gradle scissors. The tip has a curvature which approximates a cradle, which rhymes with gradle.
- A- 30-year-old female presents to your cosmetic dermatology clinic hoping to improve severe atrophic acne scarring on both cheeks which has been present since adolescence. Which of the following is the preferred resurfacing modality and gold standard to improve this patient’s scarring?
A. Pulsed dye laser
B. Motorized dermabrasion
C. Intense pulsed light
D. Carbon dioxide laser
E. 35% trichloroacetic acid chemical peel
Correct choice: B. Motorized dermabrasion
Explanation: Moderate to severe acne scarring is the most notable condition for which motorized dermabrasion is the preferred resurfacing modality. Laser resurfacing has yielded variable results and chemical peeling is generally disappointing. Dermabrasion selectively planes the affected skin. Carbon dioxide laser ablation and trichloroacetic acid chemical peels may efface the edges of atrophic scars but are more difficult with less predictable results compared to dermabrasion. Conventional motorized dermabrasion remains the gold standard in resurfacing procedures for atrophic or boxcar acne scars.
1 – Pulsed dye laser is not an effective resurfacing treatment option for moderate to severe acne scarring. 3 – Intense pulsed light is not an effective resurfacing treatment option for moderate to severe acne scarring. 4 – Effacing the edges of atrophic scars can be accomplished with the carbon dioxide laser but may be more difficult and with less predictable results compared to dermabrasion. 5 – Chemical peels are generally disappointing for moderate to severe acne scarring. Effacing the edges of atrophic scars can be accomplished with a 35% trichloroacetic acid peel but is more difficult and has less predictable results compared with dermabrasion.
89- What artery is often encountered during this repair?
A. Angular artery
B. Inferior labial artery
C. Supratrochlear artery
D. Supraorbital artery
E. Anterior ethmoidal artery
Correct choice: A. Angular artery
Explanation: The angular artery courses up the nasolabial fold and is deep to the nasal alar groove and is often encountered with this V to Y repair. The other arteries are not located in this area. The anterior ethmoidal nerve supplies sensation to the columella and nasal tip.
90- The operational wavelength of the most common laser used to treat the disorder depicted in this image is:
A. 1064 nm
B. 308 nm
C. 595 nm
D. 755 nm
E. 532 nm
Correct choice: B. 308 nm
Explanation: The operational wavelength of the 308 nm excimer laser and lamp is close to that of NB-UVB. The therapeutic benefit of the excimer laser for vitiligo has been investigated in multiple studies, and, overall, 20–50% of lesions achieve ≥75% repigmentation; the excimer lamp appears to have similar efficacy. Localized patches of vitiligo are treated one to three times weekly for an
average of 24 to 48 sessions, with the repigmentation rate depending on the total number of sessions, not their frequency. Erythema and (rarely) blistering represent potential side effects.
91- Which filler is least likely to cause nodules in the area indicated?
A. Poly-L-lactic acid
B. Hyaluronic acid
C. Polymethyl methacrylate
D. Silicone
E. Calcium hydroxyapatite
Correct choice: B. Hyaluronic acid
Explanation: Hyaluronic acid. Poly-L-lactic acid (Sculptra), polymethyl methacrylate (Artefill/ Artecoll), silicone and calcium hydroxyapatite (Radiesse) are all much more likely to cause nodules in the perioral area than hyaluronic acid fillers.
92- What is the purpose of this design?
A. To increase eversion of the wound
B. To increase the length of the wound
C. To avoid important anatomic structures
D. To provide better hemostasis
E. To increase wound tension
Correct choice: C. To avoid important anatomic structures
Explanation: This is a diagram of a M-plasty, which is used to shorten the length of a scar in order to avoid important anatomic structures. The other choices are untrue.
93- What is the etiology of this complication?
A. Poor hemostasis
B. Poor blood supply
C. Pulling sutures too tight
D. Not enough undermining
E. Too large of a flap for the defect
Correct choice: D. Not enough undermining
Explanation: This is a photograph of trap door deformity which occurs when not enough undermining is performed.
94.A- 60-year-old man presents with a tendency to flush combined with a background of persistent facial erythema. On exam, you notice a background of telangiectasias. He has maximized treatment with topical and oral medications and is considering laser treatment for his prominent blood vessels. Which is the laser of choice for this patient’s condition?
A. Pulsed dye laser
B. KTP laser
C. Intense pulsed light
D. Diode laser
E. Nd:YAG laser
Correct choice: A. Pulsed dye laser
Explanation: The pulsed dye laser (PDL) is considered to be the laser of choice for the treatment of many cutaneous vascular lesions, especially facial telangiectasias, port-wine stains, superficial hemangiomas, poikiloderma of Civatte, and erythematotelangiectatic rosacea.
B - KTP laser: KTP laser can be used to effectively treat some vascular lesions (e.g. telangiectasias) in a purpura-free manner. While it can be used to treat vascualr lesions including telangiectasias, pulsed dye laser is the laser of choice for treatment of cutaneous vascular lesions such as telangiectasias.
C - Intense pulsed light: IPL is most commonly used for patients with phototypes IIII with chronic photodamage or for hair removal. For treatment of patients with more darkly pigmented skin, longer wavelength filters or lower fluences plus longer pulse widths can be used. Filters can also be used for other specific indications, e.g. treatment of vascular lesions. Although it can be used to treat vascular lesions, PDL is considered to be the laser of choice for treatment of facial telangiectasias. D - Diode laser: Diode lasers can be used to treat leg venulectasias and telangiectasias (“spider veins”), blue reticualr veins, and venous malformations. However, a pulsed dye laser is considered to be the laser of choice for treatment of facial telangiectasias.
E - Nd:YAG laser: The deeply penetrating Nd:YAG 1064 nm laser has significantly less hemoglobin absorption than the wavelengths of the PDL or KTP lasers. This laser can be used to treat deeper vascular lesions and spider veins up to 3 mm in size. Because of its poor coefficient of absorption by hemoglobin, much higher fluences are required to produce transmural heating of blood vessels. Nd:YAG lasers should be used with extra caution when treating vascular lesions.
95- What laser wavelength best targets these lesions?
A. 1550nm
B. 10600nm
C. 532nm
D. 755nm
E. 2940nm
Correct choice: C. 532nm
Explanation: These are telangiectasias which are most effectively treated with the long pulsed 532nm KTP laser. The 1550nm, the CO2 10600nm and the erbium 2940nm lasers target water and do not target the hemoglobin. The alexandrite 755nm targets melanin not hemoglobin
96- A 55 y/o male has multiple skin tags on the upper eyelids and presents to discuss cosmetic removal. Which of the following instruments would be the most appropriate tool to remove these lesions?
A. Large Metzenbaum scissors
B. Spencer scissors
C. Baby Metzenbaum scissors
D. Obrien scissors
E. Gradle scissors
Correct choice: E. Gradle scissors
Explanation: Gradle scissors have delicate sharp tips, making them ideal for skin tag removal. Obrien scissors and Spencer scissors are suture scissors. Obrien scissors have angled tips, whereas Spencer have a characteristic round suture hook. Baby and large Metzenbaum scissors have blunt tips and are used for undermining tissue.
97- This patient presents for Mohs surgery. What is the deepest layer that you can undermine in this area?
A. Superficial muscular aponeurotic system (SMAS)
B. Muscle
C. Subcutaneous fat
D. Dermis
E. Epidermis
Correct choice: C. Subcutaneous fat
Explanation: To avoid injury to the temporal branch of the facial nerve in this area, undermining should occur in the subcutaneous fat layer. Undermining deeper than the subcutaneous fat layer (SMAS or muscle) could risk injury to the temporal branch of the facial nerve.
98- A patient develops steroid atrophy 1 cm in size after intralesional steroid for acne cyst on the right cheek. What is a reasonable, least costly, and minimally invasive first step?
A. Microneedling with platelet rich plasma to the area involved
B. Excision of area with intermediate layered linear repair
C. Serial normal saline injections to the area
D. Fat transfer from the abdomen to the area
E. Hyaluronic filler injection to the area
Correct choice: C. Serial normal saline injections to the area
Explanation: Saline injections in serial fashion are the least invasive, least costly option to offer the patient. Injections are performed every 1-2 weeks for at least 2 months before evaluating for success or failure. The remaining choices are incorrect as the first, least invasive option.
99- A 75 y/o male presents with a lesion - biopsy is shown below. Which of the following antiseptics was likely used in the excision of this lesion?
A. Isopropyl alcohol
B. Hexachlorophene
C. Povidone-iodine
D. Normal Saline
E. Chlorohexidine
Correct choice: C. Povidone-iodine
Explanation: The image shows a pathologic photo of sebaceous carcinoma. The most common location of sebaceous carcinoma is the upper eyelid. Given this location, povidone-iodine is the best answer. Of note, it must be allowed to completely dry before starting surgery. Chlorohexidine’s exposure to the eyes can cause keratitis and therefore should be avoided in these areas.
Isopropyl alcohol has not demonstrated toxic effects on the eyes and can be used safely, but is typically too short acting for surgery. Hexachlorophene causes neurotoxicity and is teratogenic so is rarely used today. Normal Saline has not demonstrated toxic effects on the eyes and can be used safely, but does not have antiseptic properties.
100- What filler is contraindicated in this area?
A. Poly-L-lactic acid
B. Calcium hydroxyapatite
C. Silicone
D. Bovine collagen
E. Hyaluronic acid
Correct choice: D. Bovine collagen
Explanation: Bovine collagen is contraindicated in the glabella due to necrosis, however, extreme caution must be used when injecting any filler in the glabellar region as it is a watershed area.
Injection necrosis is a rare but clinically important potential complication caused by interruption of the vascular supply to the area by compression, injury, and/or obstruction of the vessel(s). The glabella is a particular danger zone for injection necrosis regardless of the type of filler used, however bovine collagen poses a greater risk of developing this side effect.
101- You perform a melanoma excision on a patient’s back and leave it open to wait for pathology results. On day 5, results come back with clear margins. You call the patient back and perform an intermediate layered closure on day 5. How would you bill this repair on day 5?
A. 12032 with 79 modifier
B. 12032 with 58 modifier
C. 12032 with 25 modifier
D. 12032 with 59 modifier
E. 12032
Correct choice: B. 12032 with 58 modifier
Explanation: This question describes a malignant excision, which has a 10 day global period. Therefore, the repair that was performed on day 5 in this scenario falls into this global period. Given this, the repair code 12032 will require a modifier. The correct answer is the 58 modifier, which describes a related/staged procedure by the same physician within a global period.
The 25 modifier designates a separate E/M on the same day as a procedure.
The 59 modifier is a clinically distinct procedure performed on the same day by the same physician. The 79 modifier designates an unrelated procedure by the same physician in a global period.
102- What is the optimal angle for the apices of this surgical procedure?
A. 45
B. 30
C. 60
D. 90
E. 15
Correct choice: D. 30
Explanation: This is an ellipse, and the optimal angle between the apices is 30 degrees. In rhombic transposition flaps, the rhombus consists of two 60-degree angles and two 120-degree angles.
103- A patient presents to you for a new rash on the trunk. You had previously performed Mohs Surgery 60 days ago for a BCC on the nose, repaired with a bilobed transposition flap. How would you code this visit?
A. 99213 with 59 modifier
B. 99213 with 25 modifier
C. 99213 with 24 modifier
D. 99213 with 79 modifier
E. 99213
c
Correct choice: C. 99213 with 24 modifier
Explanation: Adjacent tissue transfer/Flap reconstruction after Mohs surgery has a 90 global period. This visit is an unrelated E/M during a global period, and would therefore require a modifier 24.
Modifier 25 designates a procedure on the same day/visit as an E/M.
Modifier 59 designates 2 separate and distinct procedures were performed on the same day. Modifier 79 is a separate procedure performed by the same physician during a global period.
104- In solid organ transplant recipients, all of the following risk factors increase susceptibility to the development of post-transplant skin cancer EXCEPT:
A. Thoracic organ transplantation
B. Fair skin (Fitzpatrick types I-III)
C. Immunosuppression with mTor inhibitor
D. Increased age at time of transplant
E. Male sex
Correct choice: C. Immunosuppression with mTor inhibitor
Explanation: All organ transplant recipients are at increased risk for the development of cutaneous malignancies. However, the above-mentioned factors, with the exception of choice E, place these individuals at further risk. Sirolimus (mammalian target of rapamycin inhibitor) has shown evidence of decreasing the risk of post-transplantation skin cancer incidence. Post-transplant skin cancer is common, with elevated risk imparted by increased age, white race, male sex, and thoracic organ transplantation.
105- A 69 y/o patient presented to her ophthalmologist with burning pain, tearing, and blurred vision in one of her eyes. She reported that she had a cosmetic procedure performed at a local med spa the day prior. What procedure did she likely have performed?
A. All procedures could have caused this injury
B. Q-switched Alexandrite for facial lentigines
C. KTP for nasal telangiectasias
D. PDL for facial redness
E. CO2 laser resurfacing for facial wrinkles
Correct choice: E. CO2 laser resurfacing for facial wrinkles
Explanation: This stem describes a woman with a corneal ulceration. This typically presents with burning pain at the site of exposure followed by tearing and blurred vision.
CO2 lasers have wavelengths of 10,600 nm which targets the chromophore of water. Lasers > 800 nm can damage the cornea, which is a water containing structure. Therefore, exposure of CO2 to the eye can cause corneal injuries. Nd:YAG (1320 nm), diode (1440 nm), Er:glass (1550 nm), Er:YAG (2940 nm) can also cause corneal damage.
Lasers < 800 nm damage the retina, iris, uvea, and choroid (pigment-containing structures). PDL has target wavelength of 585-595 nm
Q-Alex has target wavelength of 755 nm KTP has target wavelength of 532 nm
These wavelengths are therefore too short to damage the cornea.
106- What nerve innervates this structure?
A. Infratrochlear
B. Anterior ethmoidal
C. Infraorbital
D. Zygomaticotemporal
E. Buccal
Correct choice: B. Anterior ethmoidal
Explanation: The external nasal nerve innervates the columella and nasal tip. It is a branch of the anterior ethmoidal nerve, which provides branches of V1. The infratrochlear is also a branch of V1 but it supplies the nasal root and medial canthus. The infraorbital and zygomaticotemporal are branches of V2. The buccal is a branch of V3.
Most of the sensory innervation of the nasal cavity is derived from two sources: the sphenopalatine ganglion and the anterior ethmoidal nerve. The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is a parasympathetic ganglion that is located in the pterygopalatine fossa, posterior to the middle turbinate. Its sensory root is derived from sphenopalatine branches of the maxillary nerve, cranial nerve (CN) V2. As they pass through the sphenopalatine ganglion, these sensory branches form the greater and lesser palatine nerves, which provide sensory innervation to the nasal cavity as well as the roof of the mouth, soft palate, and tonsils. The anterior ethmoidal nerve is one of the sensory branches of the ciliary ganglion, which is located within the orbital cavity and inaccessible to nerve blocks. It provides sensory innervation to the anterior portion of the nasal cavity.
107- Which of the following is a potential side effect of ambulatory tumescent liposuction?
A. Muscle atrophy
B. Breast enlargement
C. Decreased appetite
D. Abdominal perforation
E. Pulmonary embolus
►B
Breast enlargement is a relatively common and unexpected side effect of tumescent liposuction. Since the majority of these patients report increased breast size in the absence of weight gain, some authors postulate shifting hormone ratios as the etiology of this paradoxical breast augmentation.Abdominal perforation, respiratory failure and pulmonary embolus are complications that are seen almost exclusively in liposuction patients that receive general anesthesia or intravenous sedation.
108 -Which is an advantage of a split-thickness skin graft over a full-thickness skin graft?
A. Better color match
B. Better texture match
C. Less contraction
D. Decreased infection risk
E. Improved survival
►E
The major advantage of a split-thickness skin graft over a full-thickness graft is the increased survivability. Full-thickness skin grafts have better color and texture match and less contraction. There is no significant difference in infection risk.
109 -Which of the following sutures is the first to be absorbed?
A. Catgut
B. Polyglycolic acid
C. Polyglactin 910
D. Polydioxanone
E. Polypropylene
►A
Catgut has a variable rate of absorption but typically lasts about 7-14 days. Thus, it would be the first suture to be absorbed. Polyglactin 910 (Vicryl) and polyglycolic acid (Dexon) are both absorbed in about 90 days. Polydioxanone (PDS) is an absorbable monofilament which lasts approximately 180 days. Polypropylene (Prolene) is not an absorbable suture.
110- Which of the following injectable local anesthetics is the longest lasting?
A. Lidocaine
B. Bupivacaine
C. Meppivacaine
D. Procaine
E. Diphenhydramine
►B
Bupivacaine is the longest lasting injectable local anesthetic-120-240 minutes without epinephrine, 180-420 minutes with epinephrine. Lidocaine lasts 30-60 minutes without epinephrine, 120-360 with epinephrine. Mepivacaine last 45-90 minutes without epinephrine, 120-360 with epinephrine. Procaine lasts 15-60 minutes. Diphenhydramine lasts 30 minutes.
111 -Which of the following demonstrates the highest risk of metastasis?
A. SCC on the ear
B. SCC within a scar
C. SCC on the lip
D. SCC on the scalp
E. SCC on the nose
►B
Location of tumor is an important risk factor for metastasis of squamous cell carcinoma. Compared with a 10% likelihood of metastasis for tumors located on the ear or the lip, an SCC developing in the scar, however, has been estimated to metastasize at a rate as high as 30-40%. .
112- The post-operative complication shown in the photograph is most commonly seen with which type of reconstruction?
A. Rhombic flap
B. Nasolabial flap
C. Rotation flap
D. Full-thickness skin graft
E. Secondary intention
►B
Trap door deformity is believed to result from insufficient undermining. This surgical complication is most often associated with the nasolabial transposition flap. Intralesional corticosteroids may be beneficial in improving the cosmetic outcome.
113- Which is the following is true regarding cellulite?
A. It is caused by lipoatrophy of fat.
B. Adipocytes in the gluteofemoral region are more responsive to lipolysis.
C. Norepinephrine is the only hormone that affects lipolysis.
D. It occurs in up to 50% of postpubertal females.
E. Caucasian women tend to get cellulite more than Asian women.
►E
According to the JAAD CME article in March 2010, cellulite is caused by the herniation of subcutaneous fat, not lipoatrophy, within fibrous connective tissue. It is prevalent in almost all postpubertal females. It is most notable in the pelvic region, lower limbs, and abdomen. The adipocytes in the gluteofemoral region are larger and are influenced by female sex hormones. They
are metabolically more stable and resistant to lipolysis. The hormones that acutely affect lipolysis in adipocytes are catecholamines (epinephrine and norepinephrine) and insulin.
114- Which of the following lasers has the greatest depth of penetration in the skin?
A. Pulsed dye laser (585 nm)
B. Diode (800 nm)
C. Nd: YAG (1064 nm)
D. Erbium: YAG (2940 nm)
E. CO2 (10,600 nm)
►C
The Nd: YAG laser emits energy at 1064nm near the infrared range and penetrates the skin to the level of the deep dermal blood vessels. The target chromophore for this laser is melanin, thus its primary use is in treating lesions such as nevus of Ota and removing black tattoo pigment. Although both the erbium:YAG and CO2 lasers have longer wavelengths than the Nd: YAG, they are ablative lasers which only penetrate to the level of the stratum corneum and superficial epidermis, respectively.
115- The maximum dose of lidocaine with epinephrine when used in tumescent anesthesia is:
A. 3 mg/kg
B. 4.5 mg/kg
C. 7 mg/kg
D. 20 mg/kg
E. 50 mg/kg
►E
The maximum recommended dosage of lidocaine in adults is 4.5 mg/kg without epinephrine, 7.0 mg/kg with epinephrine, and 55 mg/kg in tumescent anesthesia for liposuction.
116 -Which of the following chemical peels does not need to be neutralized?
A. Salicylic acid
B. TCA 40%
C. Glycolic acid
D. Lactic acid
E. Phenol
►A
Salicylic acid is a very superficial chemical peel that is used for acne, milia, keratolysis. This peel localizes to the pores given its lipophilic nature. It is a self-neutralizing peel.
117- The use of imiquimod (Aldara) for the treatment of superficial basal cell carcinoma is advocated at which treatment regimen?
A. Five times a week for 6 weeks
B. Five times per week for 4 weeks
C. Three times a week for 6 weeks
D. Three times per week for 4 weeks
E. Three times a week for 10 weeks
►A
Imiquimod (Aldara) was FDA-approved in 2004 for the treatment of superficial basal cell carcinoma. The recommended treatment schedule is once daily, five times per week for a total of six weeks. Geisse J et al. Imiquimod 5% cream for the treatment of superficial basal cell carcinoma: results from two phase III, randomized, vehicle-controlled studies.
119- The surgical instrument shown in the photograph is a:
A. Needle holder
B. Hemostat
C. Gradle scissor
D. Towel clamp
E. Iris scissor
►B
A hemostat is shown in the photograph. This instrument is commonly used in cutaneous surgery for clamping off blood vessels.
126 -The anatomic structure identified in the photograph is called the:
A. Soft triangle
B. Columella
C. Cupid‟s bow
D. Philtral ridge
E. Vermillion border
►D
The philtral ridges are located at the upper middle lip and form part of the aesthetically important cupid‟s bow.
145 -Which post-operative complication is shown in the photograph?
A. Trap door deformity
B. Hypertrophic scar
C. Ectropion
D. Temporal nerve paralysis
E. Eclabium
►C
Ectropion occurs when the eyelid margin turns outward away from the eye. In lower eyelid reconstruction, tension should be oriented parallel to the lower eyelid to prevent the development of ectropion.
147- The anatomic structure identified in the photograph is called the:
A. Nasal ala
B. Soft triangle
C. Columella
D. Philtral ridge
E. Nasal groove
►C
The columella is one of the cosmetic subunits of the nose. It is formed by the medial crura of the alar cartilage. The nasal ala forms the free margin on the lateral inferior portion of the nose and the superior aspect of the nostril. The soft triangle is located on the inferior nose and is bordered by the ala laterally, the nasal tip superomedially, and the columella inferomedially. The philtral ridge is a paired structure located on the upper cutaneous lip. The nasofacial sulcus separates the nasal sidewall from the medial cheek bilaterally.
169- Sensory innervation of the glabella and mid-forehead is provided by which nerve?
A. infratrochlear nerve
B. supraorbital nerve
C. supratrochlear nerve
D. temporal branch of the facial nerve
E. zygomatic branch of the facial nerve
►C
The supratrochlear, supraorbital and infratrochlear nerves are branches of the ophthalmic division of the trigeminal nerve, supplying sensory innervation to the face. The supratrochlear nerve exits the orbit approximately one centimete lateral to the midline and traverses upward along the medial supraorbital rim along the supratrochlear notch. It provides sensory innervation to the medial upper eyelid and glabella, the medial anterior forehead, and the scalp. The supraorbital nerve supplies the lateral forehead and scalp as well as the upper eyelid. The infratrochlear nerve provides sensory innervation to the root of the nose and to portions of the medial canthus. The facial nerve provides motor innervation to muscles of the face. The temporal branch of the facial nerve supplies motor innervation to the upper orbicularis oculi and the frontalis muscle, as well as the anterior and superior auricular muscles. The zygomatic branch of the facial nerve provides innervation to the inferior portion of the orbicularis oculi, zygomaticus minor and zygomaticus major muscles, as well as levator labii superioris.
180 -A patient undergoing Mohs surgery undergoes a rotation flap from the lateral canthus/cheek to close an infraorbital defect. What is the name of this flap?
A. Rieger flap
B. Mustarde flap
C. O to Z
D. Bilobed
E. Abbe flap
►B
This patient had a Mustarde flap, a rotation flap from the lateral canthus or cheek that close the lower eyelid or infraorbital defect. A Rieger flap is a dorsal nasal rotation flap with backcut at the glabella; it is also knows as a hatchet flap or glabellar turn-down flap. O to Z is a double rotation flap. A bilobed is a transposition flap most often used on the nose. Finally, and Abbe flap, or a lip- switch flap, is a lower lip flat of mucosa, muscle, skin, and subucutis that is transposed superiorly to the repair an upper lip defect based on inferior labial artery blood supply.
182 -The relaxed skin tension lines overlying the scapula are:
A. Do not exist over the scapula
B. Oriented vertically
C. Oriented circumferentially
D. Oriented horizontally
E. Perpendicular to the underlying muscle groups
Relaxed skin tension lines (RSTLs) are creases in the skin that are present at rest and develop as a consequence of the decreased elasticity that occurs with aging and solar damage. These lines lie perpendicular to the underlying musculature. They tend to run diagonally on the upper back whereas on the central trunk, they are typically circumferential. Knowledge of RSTLs is important in cutaneous surgery because placing incisions within these lines will ensure the most favorable cosmetic result.
184 -The type of repair depicted in the photograph is a:
A. Rhombic flap
B. Nasolabial flap
C. Rotation flap
D. Full-thickness skin graft
E. Island pedicle flap
►E
The island pedicle flap is a type of advancement flap commonly used for medial ch eek defects. The closure can often be camouflaged in the melolabial fold.
188- The rhytids identified in the photograph are referred to as:
A. Marionette lines
B. Relaxed skin tension lines
C. Crow‟s feet
D. Nasolabial folds
E. Bunny lines
►E
Bunny lines are located on the dorsum of the nose and are formed by the contraction of the nasalis muscle. Marionette lines form at the lateral oral commissures and run inferolaterally toward the jawline just over and lateral the region of the depressor anguli oris muscle. Crows feet lines radiate from the lateral canthal region and are caused by the orbicular oculi contraction. Nasolaial foles run from the apical triangle of the upper cutaneous lip down lateral to the oral commissures and are caused by dynamic facial muscle movements and fat pad atrophy over time. Relaxed skin tension lines run perpendicule to underlying muscle orientation.
195 -The following flaps are types of transposition flaps except:
A. Rhombic flap
B. Nasolabial
C. Bilobed
D. A to T
E. Z plasty
►D
The Z plasty, Bilobed, Rhombic, nasolabial flaps are all examples of transposition flaps. In each of these, the flap is transposed over a normal piece of skin to be placed in the recipient site. Whereas, the A to T flap, is an advancement flap, in which tissue is moved in a linear direction to cover the defect.
201 -What nerve innervates the skin between the 1st and 2nd toes?
A. saphenous nerve
B. posterior tibial nerve
C. sural nerve
D. superficial peroneal nerve
E. deep peroneal nerve
►E
deep peroneal nerve innervates the skin between the 1st and 2nd toes. The saphenous innervates the instep and medial ankle. The posterior tibial innervates the heel and middle sole of the foot. The sural nerve innervates the 5th toe and lateral side of the sole. The superficial peroneal nerve innervates the skin of the toes other than the outside of the 5th toe and in between the 1st and 2nd toes.
202 -Injection of Botox at the location identified in the photograph would denervate which muscle?
A. Orbicularis oculi
B. Frontalis
C. Corrugator superciliaris
D. Procerus
E. Levator palpebrae superioris
►D
The development of vertical glabellar frown lines is due to the overactivity of the orbicularis oculi, procerus and corrugator supercilaris muscles. These muscles function to pull the eyebrow inferomedially.
239- The O to Z flap is what type of flap?
A. Rotation
B. Advancement
C. Transposition
D. Pedicle
E. Bilobed
►A
The O to Z flap is a bilateral rotation flap in which tissue is moved from two ends to cover a central defect. It is often used on the scalp or lower extremities in locations where tissue laxity is not present.
249- When would use of this technique be most beneficial?
A. To prevent post-operative bleeding
B. To prevent post-operative infection
C. To shorten the length of the wound
D. To increase the width of the wound
E. To prevent pincushioning
►C
M-plasty is used to shorten wound length and is often when it is not desirable to extend the ellipse into a nearby structure.
This becomes important when reconstructive efforts lie adjacent to important nearby free margins or cosmetic subunit junctions.
M-plasty repair does not decrease the risk of post-operative bleeding or infection, nor does it
lengthen the wound or decrease pincushioning in any meaningful way
264- Which material is used to coat the jaws of the needle holder in the photograph?
A. Gold
B. Tungsten carbide
C. Copper
D. Stainless steel
E. Nickel
►B
Tungsten carbide is believed to be a harder more durable material that allows for better grasping of the needle. Needle holders with tungsten carbide jaws usually have gold-plated handles.
270- The repair demonstrated in the photograph is a:
A. Split-thickness skin graft
B. Interpolation flap
C. Full-thickness skin graft
D. Rotation flap
E. Transposition flap
►B
The postauricular flap is useful for repairing extensive defects of the helical rim, particularly when cartilage is involved. It is an example of an interpolation flap.
272- The type of repair depicted in the photograph is a:
A. Rhombic flap
B. Nasolabial flap
C. Rotation flap
D. Full-thickness skin graft
E. Island pedicle flap
►A
The rhombic flap is a type of transposition flap. The classic rhombic flap is designed with two 60 degree angles and two 120 degree angles. The point of maximum tension is at the closure of the donor site.
273 -The following are true statements regarding the design of an excisional ellipse except:
A. Ellipse includes pathologic and normal tissue
B. Length of ellipse is at least 3 times its total width
C. The angle at each of the apices is 15º
D. Incision lines are placed in relaxed skin tension lines
E. Long axis of ellipse is oriented perpendicular to free margins
►C
Thoughtful design of an elliptical excision is important for obtaining optimum tissue diagnosis, tumor clearance, wound closure and cosmetic result. The above statements are all true except that the angles at the apices of the ellipse should be 30º.
A properly designed ellipse should be at least three times as long as it is wide, include the lesion of interest with proper margins, and have 30 degree apical angles. Repair of surgical defects should always attempt to: 1) maintain function 2) preserve free margins 3) respect cosmetic subunit
boundaries 4) hide scar in relaxed skin tension lines.
281 -Treatment with which modality would be most effective for the patient shown?
A. Pulsed dye laser
B. Intense pulsed light
C. Photodynamic therapy
D. Radiofrequency
E. Erbium:YAG laser
►B
The patient shown has multiple solar lentigines. Targeting the melanosomes in these benign, superficial pigmented lesions would be most successfully accomplished with the intense pulsed light source.
Surgical scissors (left to right): O’Brien, straight suture, Gradle.
Surgical scissors (left to right): Westcott, iris (tungsten carbide), baby Metzenbaum, Metzenbaum.
Bandage scissor
Needle holders (left to right): Halsey, MayoHegar, Castroviejo
calpel handles (left to right): Round knurled handle, Beaver blade handle, #3 handle.
Blades used in dermatologic surgery (left to right): #10, #15, #15c, #11.
Forceps (left to right): Jeweler’s forceps, Adson forceps without teeth, Adson forceps with teeth, BishopHarmon forceps.
Nail surgery instruments (top to bottom): Nail elevator and English nail splitter.
Single- and double-pronged skin hooks.
Fox dermal curette.
Chalazion clamp
Mosquito hemostat
