PHOTOSCLEROSIS. HOW DO LASERS AND LIGHT SOURCES WORK?
Lasers and light sources are based on the principle of selective photothermolysis formulated by Anderson and Parris. This principle consists in the emission of monochromatic light (laser) that is specifically uptaken by a colour. The cells containing that particular colour, complementary to each particular type of laser, absorb the light radiation and heat the target destroying it with no damage to surrounding tissues.
Invented in the early 80´s by Anderson and Parris, the principle of selective photothermolysis has now been improved by the extended theory of photothermolysis postulated by Alshuter. This theory defines the pigment that is going to be heated based on its colour as the “heater” and the tissue structure that we aim to destroy as the “target”. In the veins, the heater is the blood and the target is the actual vein. That is, the heating of the heater must cause damage to the venous endothelium so that the process of vascular sclerotisation is started. In contrast with chemical sclerosis and in response of the dermal damage caused to the dermis, a laser is capable of inducing 2 proteins responsible for tissue repair: heat shock protein 70 (hsp 70) and tissue growth factor 2 (GFT2). The advantage of these substances is that they promote reabsorption phenomena in the damaged tissues or veins, repairing the deepest dermis with less change of re-canalisation of the vein, as it occurs in chemical sclerosis.
In the case of veins, it should be taken into account that lasers shoot at the red colour of the blood, that is, at the haemoglobin contained inside red cells. Once heated these red cells will cause dermal damage to the wall of the vein, inducing coagulation and subsequent fibrosis. This explains why the method is called “photosclerosis” (light-induced sclerosis)
There are several systems currently on offer at the market , with different laser systems and outstanding marketing messages on their greater or lesser effectiveness, which often confuse the patient . We believe that above explanations, although difficult and quite technical, might help you understand how lasers work in the treatment of varicose veins.