Superficial laser vulvectomy. II. The anatomic and biophysical principles permitting accurate control over the depth of dermal destruction with the carbon dioxide laser.

The rationale for using the carbon dioxide laser to treat either vulvar intraepithelial neoplasia or extensive papillomaviral infections is to destroy the entire area of abnormal epithelium to a shallow depth, so that rapid healing will occur from normal keratinocytes in the underlying pilosebaceous glands. After the first laser impact, anatomic landmarks in the crater base are disguised by a layer of charred proteins, and any structure that is visible will already have suffered thermal necrosis. Accurate control of depth depends upon special surgical strategies that correlate the level of the underlying zone of thermal necrosis with specific visual appearances within the zone of vaporization. Maneuvers that limit depth of penetration to one of three desirable surgical planes (basement membrane, papillary dermis, midreticular dermis) are described.