Laser Resurfacing:
- Several types of lasers
- Ablative, nonablative, and fractional
- Ablative laser resurfacing involves selective thermal destruction and wounding to the level of the dermis
- Wound healing originates from cells in the dermis and inflammatory cells recruited to the site of injury leading to remodeling and production of firmer, smoother skin
- Patients with Fitzpatrick skin type I to IV are good candidates
- Can be used to treat fine and deep rhytids, uncontrollable acne, acne scars, telangectasias, and actinic keratoses
- Fractional Lasers
- Deliver columns of spatially confined thermal injury to the skin, with surrounding unaffected follicular units aiding in skin remodeling
- Effective for treatment of acne scarring and photoaging
- Nonablative Lasers
- Heat tissue but do NOT ablate
- Main benefit – Minimizes side effects when compared to albative lasers
Specific Lasers
CO2 lasers
- Used for laser skin resurfacing
- Wavelength is 10,600, Chromophore is water
- Important to stop isotreinoin or acutane for 12-18mo prior
- Hyperpigmentation is most common adverse effect of laser resurfacing for Fitzpatrick Type III or IV
- Treat with hydroquinone and tretinoin, usually resolves within a few months.
- Rates of hyperpigmentation reduced by pretreatment with retinoic acid and bleaching agents
- Erythema is normal and can last 1-4 months depending on type of laser used
- Ascorbic acid can be used decreases duration and severity of erythema
- Hypopigmentation is the main long term complication
Er: YAG:
- Treatment of choice for ablative resurfacing of skin
- Wavelength is 2940, chromophore is water
- Compared to CO2 laser – decreased thermal heating, minimal contraction of dermis, creates transudative wound (photomechanical), less coagulative necrosis, decreased permanent hypopigmentation
Specific lesions
Vascular lesions
- Lasers used to damage vessel intima and cause contraction collagen surrounding vessel
- PDL
- Wavelength 585, Chromophore is oxyhemoglobin
- Used for capillary lesions (Port wine Stains)
- KTP
- Wavelength of 532, oxyhemoglobin is chromophore
- Used for superficial vascular telangectasias, red facial capillaries
- Nd: Yag
- Wavelength 1064
- Can be used for venou and venolymphatic malformations or hemangiomas
Acne Scars
- Can be treated with infared lasers like Ed:YAG, diode, and erbium (infrared lasers at wavelengths 1064 to 1540)-
Tattoo removal
- Q-switched lasers are used (includes ruby, ND:yag, alexandrite).
- Colors
- Dark ink (black/blue) – Nd: YAG 1064
- Green ink – Alexandrite
- Red inks (purple, red, brown) – KTP 532
- Yellow/orange – highly resistant to treatment
Laser hair removal
- Targets melanin in hair follicle
- Lasers used – Diode, Alexandrite, Nd: Yag 1064, intense pulsed light 4000-1300nm (best for facial hair)
- Not useful in fair haired patients due to lack of melanin
- Electrolysis used for hair removal in fair skin patients
- Safety
- Reactivation of HSV is most common infectious complication after resurfacing
- Antiviral prophylaxis should be used in all patients undergoing laser resurfacing
- Herpes outbreak despite oral management: IV antiviral and antibiotic
- High-efficiency smoke evacuator placed within 1 to 2 cm of the smoke plume, high-filtration or laser masks should be used instead of standard surgical masks
- To prevent fire for laser: use conscious sedation, nerve blocks, and no supplemental oxygen