Hair removal using a long-pulsed alexandrite laser.

Human hair has few minor physiologic functions, yet its presence or absence in certain areas of the human body is a source of ongoing fascination and frustration for many individuals. Hirsutism and hypertrichosis are of particular cosmetic concern in Western culture, fueling a constant search for new remedies or removal techniques. Over the past 10 years, various lasers have been employed in an attempt to develop a method of permanent hair removal in the safest and most expedient manner. Numerous wavelengths have been used attempting to take advantage of selective photothermolysis. 2 The long-pulsed alexandrite (LPA) laser (755 nm) is a recently developed laser for depilation. To understand the method by which the LPA and other lasers produce significant hair reduction one must first understand the complex embryology, anatomy, and physiology of the hair follicle unit. In addition, the basic definitions and causes of hirsutism and hypertrichosis must be understood. Finally, an understanding of laser/tissue interactions must be acquired. This article will review these concepts as well as discuss the current role of the LPA in hair reduction.