CLT Skin Rejuvenation & Resurfacing 3 — Questions and Answers
Question 1: When treating periorbital wrinkles with an ablative CO2 laser, the minimum safe distance from the eyelid margin is typically:
- 1 mm
- 3 mm (Correct answer)
- 5 mm
- 8 mm
Correct answer: 3 mm
Treating within 3 mm of the eyelid margin risks ectropion, corneal damage, and scarring due to thin, delicate tissue.
Question 2: Antiviral prophylaxis before ablative laser resurfacing is recommended primarily to prevent reactivation of:
- Human papillomavirus
- Herpes simplex virus (Correct answer)
- Staphylococcus aureus
- Candida albicans
Correct answer: Herpes simplex virus
Ablative resurfacing disrupts the skin barrier and can trigger HSV reactivation, causing widespread painful eruptions across the treated area.
Question 3: What is the primary purpose of the cooling system in non-ablative laser skin rejuvenation devices?
- Enhance laser absorption by melanin
- Protect the epidermis from thermal injury (Correct answer)
- Increase treatment depth in the dermis
- Reduce treatment time per session
Correct answer: Protect the epidermis from thermal injury
Epidermal cooling protects the superficial skin layers while allowing the laser energy to heat deeper dermal structures for collagen stimulation.
Question 4: Which endpoint is typically observed during a properly performed erbium:YAG ablative pass?
- Gray-white tissue discoloration
- Pink chamois-like appearance of dermis (Correct answer)
- Immediate blistering
- Pinpoint bleeding without coagulation
Correct answer: Pink chamois-like appearance of dermis
A pink chamois-leather appearance indicates correct papillary dermal depth, confirming adequate ablation without excessive thermal damage.
Question 5: A patient with a history of isotretinoin use within the past 12 months presents for fractional CO2 resurfacing. The appropriate action is to:
- Proceed with reduced fluence settings
- Postpone treatment for at least 6–12 more months (Correct answer)
- Perform non-ablative treatment only
- Request isotretinoin levels before proceeding
Correct answer: Postpone treatment for at least 6–12 more months
Isotretinoin impairs sebaceous gland function and wound healing, increasing the risk of scarring; most guidelines recommend waiting 12–24 months after cessation.
Question 6: In the context of laser resurfacing, 'fractional photothermolysis' means the laser:
- Targets only the dermal layer
- Treats a fraction of the skin surface leaving untreated zones for healing (Correct answer)
- Uses fractionated pulses with variable energy
- Combines two different wavelengths in a single device
Correct answer: Treats a fraction of the skin surface leaving untreated zones for healing
Fractional photothermolysis creates microscopic treatment zones surrounded by untreated tissue, which accelerates healing and reduces downtime.
Question 7: Which wavelength laser is considered 'water-specific' and produces minimal char due to its high absorption in tissue water during resurfacing?
- CO2 (10,600 nm)
- Er:YAG (2,940 nm) (Correct answer)
- Nd:YAG (1,064 nm)
- Alexandrite (755 nm)
Correct answer: Er:YAG (2,940 nm)
Er:YAG at 2,940 nm has the highest absorption coefficient in water of any clinical laser, enabling precise ablation with minimal residual thermal damage.
CLT Skin Rejuvenation & Resurfacing 3
When treating periorbital wrinkles with an ablative CO2 laser, the minimum safe distance from the eyelid margin is typically: