Laser Resurfacing Indian Medical PG Practice Questions and MCQs
Practice Indian Medical PG questions for Laser Resurfacing. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Laser Resurfacing Indian Medical PG Question 1: Which of the following statements about burn management is correct?
- A. Cool (not ice-cold) water should be applied for 10-20 minutes to reduce tissue damage
- B. All partial-thickness burns require sterile dressing to prevent infection
- C. Silver sulfadiazine is contraindicated in patients with sulfa allergies
- D. Escharotomy is indicated for circumferential burns causing compartment syndrome (Correct Answer)
Laser Resurfacing Explanation: ***Escharotomy is indicated for circumferential burns causing compartment syndrome***
- **Escharotomy** is a critical surgical procedure performed for circumferential full-thickness burns that cause **compartment syndrome**, impaired circulation, or respiratory compromise (in chest burns)
- The hardened eschar acts as a tourniquet, restricting blood flow and causing vascular compromise
- This is a **definitive indication** and represents correct burn management protocol
- Escharotomy involves incising through the full-thickness eschar to release the constriction
*Cool (not ice-cold) water should be applied for 10-20 minutes to reduce tissue damage*
- While this statement is **medically correct** and represents appropriate first aid for burns
- Cooling with cool (not ice-cold) water for 10-20 minutes is the standard initial treatment to reduce pain and limit tissue damage
- However, in the context of this question focusing on comprehensive burn management principles, the escharotomy statement is more specific and clinically critical
*All partial-thickness burns require sterile dressing to prevent infection*
- This statement is **incorrect** as worded with the absolute term "all"
- Small superficial partial-thickness burns may only require **clean, non-adherent dressing** rather than sterile dressing in routine first aid settings
- Not all partial-thickness burns require the same level of sterile technique; depends on size, location, and clinical setting
*Silver sulfadiazine is contraindicated in patients with sulfa allergies*
- While this statement is **medically accurate** (silver sulfadiazine contains sulfonamide and should be avoided in sulfa-allergic patients)
- However, this represents a specific contraindication rather than a general principle of burn management
- Other topical agents like bacitracin or mupirocin can be used as alternatives
Laser Resurfacing Indian Medical PG Question 2: Treatment of erythroplakia
- A. Radiotherapy
- B. Excision and regular follow up (Correct Answer)
- C. Excision
- D. Steroid injection
Laser Resurfacing Explanation: ***Excision and regular follow up***
- **Erythroplakia** has a high rate of **malignant transformation** (up to 90% are severe dysplasia or carcinoma), making complete surgical excision essential to prevent progression.
- **Regular follow-up** is critical due to the risk of recurrence and the development of new lesions, monitoring for any further malignant changes after excision.
*Radiotherapy*
- **Radiotherapy** is generally reserved for **malignancies** or situations where surgery is not feasible, not typically for the initial treatment of erythroplakia which is a precancerous lesion.
- Its use for erythroplakia could lead to unnecessary side effects and may not remove all dysplastic tissue, increasing the risk of recurrence.
*Excision*
- While **excision** is a necessary part of the treatment, performing it without **regular follow-up** is insufficient due to the high risk of recurrence and new lesion development.
- Failure to monitor the patient closely after initial excision could lead to delayed detection of malignant transformation or new areas of dysplasia.
*Steroid injection*
- **Steroid injections** are used to treat inflammatory conditions or reduce scarring, and have **no role** in the management of erythroplakia, which is a precancerous lesion.
- This treatment would not address the underlying dysplastic changes and would allow for potential malignant transformation to continue unchecked.
Laser Resurfacing Indian Medical PG Question 3: Which of the following is a contraindication to topical steroids?
- A. Dendritic ulcer (Correct Answer)
- B. Herpetic stromal keratitis without epithelial defect
- C. Elevated intraocular pressure
- D. Non-infectious anterior uveitis
Laser Resurfacing Explanation: ***Dendritic ulcer***
- A **dendritic ulcer** is characteristic of **herpes simplex keratitis**, which is an active viral infection of the cornea.
- **Topical steroids** are contraindicated because they can suppress the immune response, leading to viral replication, corneal melt, and potentially severe vision loss or perforation.
*Herpetic stromal keratitis without epithelial defect*
- In cases of **stromal keratitis**, where the infection is deeper and an intact epithelium is present, topical steroids may be used cautiously in conjunction with antiviral agents to reduce inflammation and scarring.
- The primary concern with steroids in herpes simplex keratitis is activating viral replication in the presence of an **epithelial defect**, which is not present here.
*Elevated intraocular pressure*
- **Elevated intraocular pressure** is a known side effect of topical steroid use, especially with prolonged administration, but it is not an absolute contraindication in itself.
- It necessitates careful monitoring and may require concurrent glaucoma treatment, but the primary condition needing steroids may still warrant their use.
*Non-infectious anterior uveitis*
- **Topical corticosteroids** are the **mainstay of treatment** for non-infectious anterior uveitis to reduce inflammation and prevent complications such as synechiae and vision loss.
- The benefits of controlling inflammation in uveitis generally outweigh the risks associated with judicious steroid use.
Laser Resurfacing Indian Medical PG Question 4: YAG laser is used in the treatment of:
- A. Open-angle glaucoma
- B. Retinal detachment
- C. Diabetic retinopathy
- D. After cataract (Correct Answer)
Laser Resurfacing Explanation: ***After cataract***
- YAG laser is primarily used for **posterior capsulotomy** to treat **"after cataract"** or **posterior capsule opacification (PCO)**, a common complication following cataract surgery.
- This procedure creates an opening in the opacified posterior capsule to restore clear vision without requiring a surgical incision.
*Open-angle glaucoma*
- YAG lasers are sometimes used in **peripheral iridotomy** for narrow-angle or **angle-closure glaucoma**, but not typically for the primary treatment of open-angle glaucoma, which is managed with medications or other laser procedures (e.g., SLT).
- While YAG laser can be used for **iridotomy** in specific glaucoma types, it is generally not the go-to treatment for improving outflow in **open-angle glaucoma**.
*Retinal detachment*
- Retinal detachment is a surgical emergency typically treated with procedures like **vitrectomy**, **scleral buckle**, or **pneumatic retinopexy**.
- Lasers used for retinal issues are often **argon lasers** for creating chorioretinal adhesions to prevent or wall off detachments, not YAG lasers for the detachment itself.
*Diabetic retinopathy*
- **Diabetic retinopathy** is primarily treated with **argon laser photocoagulation** (panretinal photocoagulation or focal laser) to destroy abnormal blood vessels and reduce macular edema.
- YAG lasers are not used for the direct treatment of **diabetic retinopathy** or its associated neovascularization.
Laser Resurfacing Indian Medical PG Question 5: A lady with 50% TBSA burn with involvement of dermis and subcutaneous tissue came to the emergency department. The burns will be classified as:
- A. 3rd degree burn (Correct Answer)
- B. 2nd degree superficial
- C. 2nd degree deep
- D. 1st degree
Laser Resurfacing Explanation: ***3rd degree burn***
- **Third-degree burns** involve the entire thickness of the skin (dermis and epidermis) and often extend into the **subcutaneous tissue**, muscle, or bone.
- These burns typically appear dry, leathery, and often lack pain sensation due to nerve destruction.
*2nd degree superficial*
- **Superficial second-degree burns** involve the epidermis and the superficial part of the dermis, often presenting with **blisters** and painful, red, moist skin.
- They do not extend to the subcutaneous tissue, which is a key feature of the burn described.
*2nd degree deep*
- **Deep second-degree burns** involve the epidermis and deeper layers of the dermis, but not the entire dermis or subcutaneous tissue.
- While they can be less painful and appear dry, the involvement of **subcutaneous tissue** pushes the classification to third-degree.
*1st degree*
- **First-degree burns** only affect the epidermis, causing redness and pain but **no blistering** or damage to deeper layers.
- These are typically sunburns or minor scalds and do not involve the dermis or subcutaneous tissue.
Laser Resurfacing Indian Medical PG Question 6: A child presents with grouped vesicles on an erythematous base on the buttocks. What is the most likely diagnosis?
- A. Bullous impetigo
- B. Dermatitis herpetiformis
- C. Pemphigus
- D. Herpes simplex (Correct Answer)
Laser Resurfacing Explanation: ***Herpes simplex***
- Herpes simplex virus (HSV) classically presents with **grouped vesicles on an erythematous base**, which perfectly matches this clinical presentation.
- In **children**, HSV commonly affects the **buttocks** through autoinoculation or direct contact, especially in the diaper area.
- The lesions are typically **painful and pruritic**, and may be preceded by tingling or burning sensation.
- Diagnosis is confirmed by **Tzanck smear** (multinucleated giant cells), **PCR**, or **viral culture**.
- Treatment includes **acyclovir** or other antivirals, especially for severe or recurrent cases.
*Dermatitis herpetiformis*
- While DH does present with intensely pruritic, grouped vesicles on an erythematous base, it is **extremely rare in children** and typically presents in **adults (3rd-4th decade)**.
- Classic sites include **extensor surfaces** (elbows, knees), scalp, and buttocks, but the pediatric presentation makes this diagnosis unlikely.
- It is strongly associated with **celiac disease** and responds to **gluten-free diet** and **dapsone**.
*Bullous impetigo*
- Bullous impetigo presents with **flaccid bullae** that rupture to form **honey-colored crusts**, not grouped vesicles.
- It is a **bacterial infection** caused by *Staphylococcus aureus* producing exfoliative toxin.
- Common in **young children**, particularly in warm, humid conditions.
*Pemphigus*
- Pemphigus is **extremely rare in children** and causes **fragile bullae** that easily rupture, leading to erosions.
- Typically affects **mucous membranes first** (oral cavity), then skin.
- It is an **autoimmune blistering disease** with antibodies against desmoglein, causing intraepidermal acantholysis.
Laser Resurfacing Indian Medical PG Question 7: The following findings on Tzanck smear can be seen in:
- A. Herpes simplex
- B. Herpes zoster
- C. Paraneoplastic pemphigus
- D. All of the above (Correct Answer)
Laser Resurfacing Explanation: ***All of the above***
- The image displays multiple **acantholytic cells** (keratinocytes that have lost intercellular connections) with prominent nuclei, which are characteristic findings in several dermatological conditions.
- A **Tzanck smear** is a rapid cytological test performed by scraping the base of a fresh blister, staining with Giemsa or Wright stain, and examining under microscopy.
**Why all three conditions show similar findings:**
*Herpes simplex*
- Tzanck smear shows **multinucleated giant cells** with molding of nuclei and **balloon degeneration** of keratinocytes
- Acantholytic cells are present due to viral cytopathic effect causing cell separation
- These findings are **identical** to those seen in Herpes zoster
*Herpes zoster*
- Cannot be distinguished from Herpes simplex on Tzanck smear morphology alone
- Shows the same **multinucleated giant cells** and **acantholytic keratinocytes**
- Viral culture, PCR, or direct fluorescent antibody (DFA) testing needed for definitive differentiation
*Paraneoplastic pemphigus*
- Shows **acantholytic cells** (rounded keratinocytes with hyperchromatic nuclei) due to autoantibody-mediated destruction of intercellular adhesion
- Unlike herpes infections, typically shows acantholytic cells **without** multinucleated giant cells
- Definitive diagnosis requires direct immunofluorescence (DIF) on skin biopsy showing intercellular and basement membrane zone IgG/C3 deposition
**Note**: While Tzanck smear can show acantholytic cells in all three conditions, the **pattern differs** - herpes shows multinucleated giant cells prominently, while pemphigus shows isolated acantholytic cells. Clinical correlation and confirmatory tests are essential for accurate diagnosis.
Laser Resurfacing Indian Medical PG Question 8: A cosmetic dermatologist plans to introduce microneedling radiofrequency for acne scars. Which parameter combination would provide optimal collagen remodeling with minimal risk of thermal injury in Fitzpatrick type IV skin?
- A. Needle depth 3.5 mm, temperature 70°C, pulse duration 1000 ms
- B. Needle depth 4 mm, temperature 75°C, pulse duration 500 ms
- C. Needle depth 1.5-2 mm, temperature 60-65°C, pulse duration 100-200 ms (Correct Answer)
- D. Needle depth 0.5 mm, temperature 55°C, pulse duration 50 ms
Laser Resurfacing Explanation: ***Needle depth 1.5-2 mm, temperature 60-65°C, pulse duration 100-200 ms***
- Optimal **collagen remodeling** occurs when the tissue is heated to **60-65°C**, which triggers the denaturation of proteins and the subsequent production of new collagen and elastin.
- A depth of **1.5-2 mm** specifically targets the **papillary and mid-reticular dermis**, while the shorter pulse duration minimizes **Post-Inflammatory Hyperpigmentation (PIH)** in **Fitzpatrick type IV** skin.
*Needle depth 3.5 mm, temperature 70°C, pulse duration 1000 ms*
- Temperatures reaching **70°C** and very high pulse durations significantly increase the risk of **thermal necrosis** and bulk heating injuries.
- A depth of **3.5 mm** is often too deep for standard facial acne scarring and may damage underlying **subcutaneous structures** or cause permanent scarring.
*Needle depth 4 mm, temperature 75°C, pulse duration 500 ms*
- High temperatures of **75°C** cause excessive tissue coagulation, which can lead to localized **skin burns** and prolonged downtime.
- Excessive needle depth combined with high energy delivery poses a severe risk for **atrophic scarring** and pigmentary changes in darker skin types.
*Needle depth 0.5 mm, temperature 55°C, pulse duration 50 ms*
- A depth of **0.5 mm** is generally insufficient to reach the collagen-rich dermis required for significant improvement of **depressed acne scars**.
- A temperature of **55°C** is below the threshold for effective **collagen denaturation**, resulting in suboptimal clinical outcomes for scar revision.
Laser Resurfacing Indian Medical PG Question 9: A 50-year-old man with Fitzpatrick skin type V desires treatment for melasma. He was previously treated with triple combination cream with partial response. What would be the most evidence-based next step considering safety and efficacy?
- A. Fractional CO2 laser resurfacing
- B. Q-switched Nd:YAG laser 1064 nm with low fluence (Correct Answer)
- C. Intense pulsed light therapy
- D. TCA 35% chemical peel
Laser Resurfacing Explanation: ***Q-switched Nd:YAG laser 1064 nm with low fluence***
- This approach, often called **laser toning**, uses a long wavelength that spares the epidermis, making it the safest laser option for **Fitzpatrick skin type V** to avoid **post-inflammatory hyperpigmentation (PIH)**.
- It is a clinically sound next step for **recalcitrant melasma** that has only partially responded to first-line therapies like **triple combination cream**.
*Fractional CO2 laser resurfacing*
- This is an **ablative** treatment that causes significant thermal damage, which carries an unacceptably high risk of **PIH** and scarring in darker skin types.
- While effective for skin remodeling, it is generally contraindicated for treating melasma in **type V skin** due to the likelihood of worsening the pigmentation.
*Intense pulsed light therapy*
- **IPL** uses a broad spectrum of light which is poorly targeted for melasma in dark-skinned individuals and is frequently associated with **rebound hyperpigmentation**.
- The melanin in the surrounding **darker skin (Type V)** competes for the energy, leading to a high risk of **thermal burns** and uneven results.
*TCA 35% chemical peel*
- A 35% concentration of **Trichloroacetic acid (TCA)** is considered a **medium-depth peel**, which is generally too aggressive for patients with Fitzpatrick skin type V.
- Medium-depth peels in dark skin types are likely to cause **persistent dyschromia** or permanent **hypopigmentation**, whereas superficial peels (like glycolic or salicylic acid) are safer.
Laser Resurfacing Indian Medical PG Question 10: A patient treated with Q-switched Nd:YAG laser for nevus of Ota develops paradoxical darkening after 4 weeks. What is the most likely explanation for this phenomenon?
- A. Delayed clearance in deeper dermal melanocytes
- B. Increased melanogenesis due to suboptimal fluence (Correct Answer)
- C. Post-inflammatory hyperpigmentation due to epidermal injury
- D. Conversion to melanoma
Laser Resurfacing Explanation: ***Increased melanogenesis due to suboptimal fluence***
- Paradoxical darkening in **nevus of Ota** during **Q-switched Nd:YAG** therapy often results from **suboptimal fluence**, which triggers reactive **melanogenesis** instead of destroying the target cells.
- This occurs when the energy delivered is sufficient to stimulate **dermal melanocytes** but remains below the threshold required for **selective photothermolysis** and cell destruction.
*Delayed clearance in deeper dermal melanocytes*
- Delayed clearance typically results in a slow resolution of the lesion rather than an actual **increase in pigmentation** or darkening.
- The darkening suggests an active production of **melanin** rather than a passive failure of the lymphatic system to clear debris.
*Post-inflammatory hyperpigmentation due to epidermal injury*
- **Post-inflammatory hyperpigmentation (PIH)** usually presents as a more generalized or superficial brownish tan following **epidermal damage**.
- While common in darker skin types, the term "paradoxical darkening" in the context of dermal lesions specifically refers to the reactive stimulation of **dermal melanocytes**.
*Conversion to melanoma*
- There is no clinical or histopathological evidence that **Q-switched lasers** induce **malignant transformation** or conversion of a benign nevus to **melanoma**.
- While **nevus of Ota** has a small baseline risk of ocular or CNS melanoma, laser-induced darkening is a transient physiological response, not a neoplastic change.
More Laser Resurfacing Indian Medical PG questions available in the OnCourse app. Practice MCQs, flashcards, and get detailed explanations.
