DIR Questions Flashcards
What is the laser of choice for solar lentigines?
Targeting the melanosomes in these benign, superficial pigmented lesions would be most successfully accomplished with the intense pulsed light source.
Telangiectasias are most effectively treated by which of the following wavelengths?
- 1550 nm
- 10,600 nm CO2
- 2940 nm Er:YAG
- 755 nm Alexandrite
- 532 nm long pulsed KTP
The 1550nm, the CO2 10600nm, and the erbium 2940nm lasers target water and do not target the hemoglobin. The alexandrite 755nm laser targets melanin not hemoglobin.
These are telangiectasias which are most effectively treated with the long pulsed 532nm KTP laser.
What is the result of a marginal mandibular nerve injury?
Inability to depress and retract the lip on the affected side
The mouth would seem normal at rest, but crooked when attempting to smile.
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.
The most important function of a postoperative wound dressing is:
Providing hemostasis to a wound is the most important function of a wound dressing
What is the soft triangle of the nose?
FTSGs are more likely than STSGs to demonstrate which of the following:
- Alopecia
- Contraction
- Necrosis
- Hypohidrosis
- Hypopigmentation
Full thickness skin grafts have more adnexal structures, vessels, and structures to supply. Therefore, their metabolic demands are higher and they are more prone to necrosis. However, they are less prone to contraction, alopecia, hypohidrosis, and hypopigmentation for similar structural reasons.
STSG lack adnexal structures, they demonstrate extremely poor cosmesis due to alopecia, hypopigmentation, and hypohidrosis. They are are also prone to contraction.
Within which anatomic plane does the inferior/superior labial artery encountered in a lip wedge repair lie?
The inferior labial artery is derived from the facial artery or superior labial artery, and runs through the submucosal tissue horizontally.
The auriculotemporal nerve is a branch of what cranial nerve?
CN V3 (mandibular nerve)
What chemotherapy may have protective effects against skin cancer?
Rapamycin (also called sirolimus) is a macrolide antibiotic and a structural analog of FK 506. It is a potent immunosuppressive agent which inhibits mTOR (a member of P13K family kinases). Despite its immunosuppressive effects, preliminary data show a decreased incidence of skin cancer in organ transplant patients treated with rapamycin and postulate that it may exert a protective effect against cutaneous malignancies.
The maximum adult dosage of lidocaine is _____ without epinephrine and _____ with epinephrine.
The maximum adult dosage of lidocaine is 4.5 mg/kg without epinephrine and 7 mg/kg with epinephrine.
What divides the cosmetic units of the lower lip and chin?
Mental crease
Which of the following has the least tissue reactivity?
- Silk
- Ethilon
- Dermalon
- Prolene
- Dacron
Prolene
Ethilon, Dermalon and Dacron have low reactivity as well, but Prolene has the least reactivity
On average, how much does a full-thickness graft contract when removed from a donor site?
On the average, a full-thickness graft may contract by about 15% when removed from a donor site.
A Z-plasty represents which type of flap?
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.
What is the most effective topical treatment option for pulsed dye laser-induced purpura? Hint: it is a vitamin.
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.
What is the best choice of a wavelength of a laser to treat the changes you see here?
- 595 nm
- 1,064 nm
- 810 nm
- 755 nm
- 10,600 nm
CO2 resurfacing and ablative lasers (10,600 nm) are the best for severe rhinophyma as is seen here.
What is the most commonly associated tattoo pigment with allergic reactions - both eczematous and granulomatous?
Which tattoo pigment is most commonly associated with phototoxic reactions?
Mercuric sulfide, which appears red in color.
Of note, Cadmium sulfide is the tattoo pigment most commonly associated with phototoxic reactions. It appears yellow.
Which sclerosant is most painful and has the highest risk of cutaneous necrosis?
Hypertonic saline has the highest risk of cutaneous necrosis. The disadvantage of hypertonic saline is pain associated with injections and ulcerogenic potential.
A Z- plasty is performed to:
A Z-plasty is a type of transposition flap that may be used to lengthen a scar, reorient a scar, or break down scars into smaller subunits with a more camoflouged appearance. This can be especially helpful when the scar crosses skin tension lines or when there is distortion of free margins by a scar.
Glogau’s photoaging classification
What laser is the best choice for a cherry angioma?
- 1,450 nm
- 755 nm
- 694 nm
- 585 nm
- 510 nm
585 nm (PDL)
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)
Healing by secondary intention will offer the most favorable cosmetic result at which location?
- Nasal tip
- Malar cheek
- Chin
- Forehead
- Medial canthus
Anatomic sites lending themselves best to second intention healing, with excellent results, are the concave areas on the face. These include the medial canthus, the nose-cheek junction, the auricular concha, the preauricular cheek, and the retroauricular scalp. The nasal tip, malar cheek, chin and forehead are all convex surfaces on the face.
What laser could be used to treat granuloma faciale?
PDL (585 nm)
What type of anesthesia should be used for endovenous radiofrequency ablation or laser ablation?
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.
Which formulation of botulinum neurotoxin does not contain complexing proteins?
Incobotulinum toxin A (Xeomin)
A patient with a deep vertical frown line in the glabellar region requests Botox. Treatment will mostly target which one of the following muscles?
Although the procerus and orbicularis oculi muscles are contributory, the development of vertical glabellar frown lines is mostly due to the overactivity of the corrugator supercilaris. These muscles function to pull the eyebrow inferomedially.
Procerus muscle contraction contributes largely to the transverse (horizontal) rhytides along the nasal root. Orbicularis oculi contraction contributes to crow’s feet rhytides radiating from lateral canthal region.
Which of the following does require neutralization?
- Jessner’s
- TCA
- Salicylic acid
- Glycolic acid
- Baker-Gordon
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 other answer choices (Jessner’s, TCA, salicylic acid, and Baker-Gordon) do NOT require neutralization.
Which of the following suture materials induces the least inflammation?
- Surgical gut
- Polyglycolic acid (Dexon)
- Polyglycan 910 (Vicryl)
- Polypropylene (Prolene)
- Silk
Prolene is a nonabsorbable suture material that evokes only minimal inflammation.
Vicryl, Dexon, silk and surgical gut are associated with more inflammation than prolene.
Which of the following medications has demonstrated efficacy in the treatment of dermatofibrosarcoma protuberans (DFSP)?
- Dabrafenib
- Ipilimumab
- Gefitinib
- Erlotinib
- Imatinib
DFSP 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.
How does electrofulguration protect underlying tissue from heat?
Electrofulguration allows an electric spark to jump to the skin causing superficial epidermal carbonization, protecting the underlying tissue from heat.
What is the mechanism of action of apraclonidine (Iopidine)?
Alpha agonist which results in contraction of the superior tarsal muscle
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).
Which of the following cosmeceuticals is NOT a pigment lightener?
- Green tea
- Arbutin
- Licorice extract
- Vitamin C
- Aleosin
1. Green tea is an antioxidant and contains antioxidant polyphenols. It is NOT a pigment lightener.
2 - Arbutin: Arbutin is a naturally occurring gluconopyranoside; decreased tyrosinase activity and may inhibit melanosomal maturation.
3 - Licorice extract: Licorice extract contains liquiritin and isoliquertin, which disperse melanin, and glabridin, which inhibits tyrosinase.
4 - Vitamin C: Vitamin C may interrupt melanogenesis by interacting with copper ions.
5 - Aleosin: Aleosin is a naturally occurring hydroxymethylchromone; inhibits tyrosinase by competitive inhibition.
Which anesthetic has the shortest duration of action?
Procaine has the shortest duration of action, only lasting about 30-60 minutes. It is an ester anesthetic and is commonly used in dentistry.
Which of the following can work in a wet field?
- Electrocautery
- Electrodessication
- Electrofulguration
- Electrosection
- Electrocoagulation
Electrocautery is the only answer listed that is not a type of electrosurgery, thus it can work in a wet field as it has no current and works via heat.
The remaining answers are types of electrosurgery, which by definition utilize electric currents and thus do not work in wet fields.
What is the term used to describe the parallel nature of coherent light waves?
Collimation is the parallel nature of coherent light waves.
Monochromaticity is the emission of a single wavelength. Coherence is the term for light waves traveling in phase. Energy is the fundamental unit of work. Power is the rate of energy delivery measured in watts.
What is the desired clinical endpoint when treating tattoos or pigmented lesions with Q-switched lasers?
Tissue whitening is the desired clinical endpoint when operating a Q-switched laser.
This muscle overlies the nasal bone and attaches to the nasal root and is also responsible for the “bunny lines” of the nose.
The nasalis muscle is responsible for the foreshortening of the nose. It is responsible for the “bunny lines” that can be treated with Botox injection.
Which of the following lasers has the greatest depth of penetration into the skin?
- PDL
- KTP
- Nd:YAG
- CO2
- Erbium
Depth of penetration is proportional to wavelength until ~1200nm, as above that water is absorbed and there is increased scatter with less depth of penetration. 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.
Although both the erbium and CO2 lasers have longer wavelengths (and thus theoretically allow for deeper penetration), the chromophore for these lasers is water, which is present in such high concentrations in the stratum corneum and superficial epidermis, that the majority of the energy gets absorbed in these superficial layers.
What is a notable potential side effect of ambulatory tumescent liposuction?
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.
Yellow skin can be camoflauged with what complementary-colored foundation, yielding brown tones?
What about red skin, brown skin, and white skin?
Purple
1 - Green: Red discoloration can be camouflaged by applying a green foundation, since green is the complementary color to red.
Brown: Brown hyperpigmentation from skin conditions such as melasma, lentigines, and nevi can be camouflaged by using a white undercover foundation color.
White: Hypopigmentation and depigmentation from skin conditions such as postinflammatory hypopigmentation, congenital pigmentary disorders and vitiligo can be camouflaged by using a brown undercover foundation color.
Yellow: Yellow facial color from conditions such as solar elastosis, chemotherapy and dialysis can be camouflaged by applying a purple undercover foundation color.
What is the MOST commonly reported side effect of vismodegib?
What are other less common side effects?
The most commonly reported side effect is muscle spasm, followed by alopecia and dysgeusia.
Botulinum toxin A cleaves which protein to exert its effects?
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
An elderly lady who weighs 110 lbs. What is the maximum amount of 1% lidocaine with 2.5% epinephrine that this patient can receive?
The maximum recommended dosage of 1% lidocaine with 2.5% epinephrine in adults is 7mg/kg. The patient weighs 110 lbs (or 50 kg) which allows her 350 mg (50 x 7) or 35 ml (1% lidocaine has 10mg of lidocaine perml) of the anesthetic.
What is the name of this phenomenon? What are at least two reasons that this may have occurred?
Inadequate undermining and/or oversized flap
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.
The Shaw scalpel is used for what?
The Shaw scalpel provides the ability to cut through tissue with minimal blood loss. This instrument employs an electronically heated metal cutting blade (electrocautery) that heats up while it cuts through tissue, and coagulates fine vessels when they are divided. This instrument has been used frequently for treatment of rhinophyma and in parotid gland surgeries.
Which of the following complications has been reported with infraorbital injections of Botox?
- Nystagmus
- Blindness
- Festooning
- Astigmatism
- Photophobia
Festooning of the lower eyelid is a recently reported complication of infraorbital Botox injections. The affected patient had a prior lower lid blepharoplasty which likely weakened the orbicularis oculi muscle. The author postulates that festooning resulted from further muscle weakness due to Botox treatment.
See asterisks in photo for example of lower eyelid festooning. Dots represent a separate finding called dermatochalasis, which is not related.
What nerve gives sensation to the nasal tip and columella?
External nasal nerve, a terminal branch of the anterior ethmoidal nerve (of CN V1)
What structure is being lifted by the dissecting probe?
- Angular artery
- Transverse facial artery
- Buccal nerve
- Mental nerve
- Superior labial artery
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 (see photo).
