Chapter 8: Nonablative Fractional Laser Resurfacing

MECHANISM OF ACTION

Nonablative fractional resurfacing (NAFR) is a novel concept of skin rejuvenation that can target both epidermal and dermal conditions. NAFR produces a unique thermal damage pattern consisting of multiple columns of thermal coagulative damage, referred to as microthermal treatment zones (MTZs) (Fig. 8.1). NAFR characteristically spares the tissue surrounding each MTZ, thus allowing fast epidermal repair due to microscopic size of the wounds and short migratory distance for the viable keratinocytes present at the MTZ epidermal margins. Only a fraction of the skin of the surface area is treated.

DERMATOPATHOLOGY

MTZ reveals homogenized columns of dermal matrix and the formation of microscopic epidermal necrotic debris (MEND) (Fig. 8.2). MEND formation is thought to represent the process of elimination of the thermally damaged epidermis containing pigment by the rapidly migrating viable keratinocytes at the MTZ margins. MEND may also contain dermal structures such as the elastic fibers. Vessels in the MTZ regions can be thermally destroyed in a nonselective manner. Higher energies result in deeper and wider MTZs. Higher energies result in deeper and wider MTZs. NAFR can be helpful in the treatment of epidermal pigmentation such as melasma and lentigines due to the process of MEND formation. NAFR can also be helpful in improving rhytides and scarring due to the process of collagen remodeling and new collagen formation, induced by the dermal thermal damage.

INDICATIONS

NAFR can be an effective treatment of fine-to-moderate rhytides; acne scars, surgical, traumatic, and burn scars; melasma; dyschromia; and dermatoheliosis (Fig. 8.3).

PREOPERATIVE EVALUATION

• Significant past medical history includes history of herpes labialis, keloid or hypertrophic scar formation, oral tretinoin intake (date last course completed), topical retinoid use, tobacco use, and known drug allergies including lidocaine allergy.

• Significant past surgical history includes prior surgical treatments to the treatment sites, the dates of the procedures, the patient’s response, and the associated side effects.

• The patient should be aware of the following:

  • – Procedural discomfort.

  • – Sunburn-like sensation for several hours after the procedure.

  • – Sunburn-like postoperative erythema that may persist for 3 to 7 ...