Laser treatment of cutaneous vascular lesions: face and leg telangiectases

Abstract

In this journal you have found the paper, written by Major et al. that reports the use of Nd:YAG 1064 nm laser for the treatment of leg and facial telangiectases with very promising results. A specific vascular pulsed dye system was the first laser developed using the principles of selective photothermolysis. This theory, proposed by Anderson and Parrish in the early 1980s, predicted that chromophores (or targets) in the skin, such as haemoglobin and melanin, could be selectively destroyed by lasers that emit light at particular wavelengths and pulse durations.1 The localized absorption of laser light energy with subsequent production of heat in the target would cause selective damage without destruction of the normal surrounding and overlying skin. Since the development of the pulsed dye laser, several other lasers with vascular specificity have been introduced or reintroduced into the market. In Table 1 we present the most important vascular-specific lasers. As shown, a variety of different lasers and light sources are used in the treatment of cutaneous vascular lesions; both visible light lasers (argon, continuous wave (CW) dye, copper vapour, krypton, flashlamp-pumped pulsed (dye), invisible light lasers (diode, carbon dioxide and neodymium:yttrium–aluminium–garnet (Nd:YAG), and broad band light sources have been used. Each of these lasers and light sources have a different wavelength, pulse width and method of delivery, and it is these characteristics that determine the effect of the laser on vascular tissue. Although each type of laser has its advantages (e.g. lower cost, less cumbersome, greater reliability, dual wavelength capabilities), the pulsed dye laser has great vascular specificity and clinical effectiveness. The original pulsed dye system has been modified, further improving its clinical efficacy with fewer side-effects. For instance, the original pulsed dye lasers used a wavelength of 577 nm (corresponding to the third absorption peak of oxyhaemoglobin) and a 5-mm spot size, and it operated at a rate of one pulse every 3 s. Subsequently a 585-nm wavelength was used, allowing slightly deeper absorption without loss of vascular specificity; such laser was provided of a 10-mm spot size, which also permits deeper dermal penetration and fewer pulses to treat a specific area; and a one pulse per second (1 Hz) delivery rate, which means shorter treatment sessions. Subject acceptance of this pulsed dye system has been further enhanced by other modifications: longer pulse durations (slower and more thorough vessel heating with decreased postoperative purpura formation), concomitant cryogen spray (dynamic cooling for epidermal protection and anaesthetic effect), and elliptical spots. The current model has a 595-nm wavelength and a 1.5 ms pulse duration. Recently, the clinical efficacy and the high vascular specificity of the Nd:YAG 1064 nm laser have been highlighted. According to recent clinical reports this laser device seems to be one of the first choice lasers for the treatment of deep dilated vessels, in particular for leg telangiectases. However, given the wide disparity of the characteristics of vascular lesions of the skin and the differences in the characteristics of the various devices, it is clear that no single laser or light source can treat all the different cutaneous vascular disorders. In some cases, more than one device may be required to treat a specific vascular lesion. Vascular lesions can be grouped according to their mode of onset, congenital or acquired. Congenital lesions (e.g. haemangiomas and port-wine stains) typically appear on the head and neck and, by definition, are observed in infants. Acquired lesions, on the other hand, can arise at any time during a lifetime and may be a result of trauma, hormone activity, actinic skin damage, or syndrome association, or they may simply present as a spontaneous disorder. A number of different congenital vascular lesions may occur in the skin. Most repr