The origin of loud claps during endovenous laser treatments.

Optoacoustic and ultrasound methods have shown that the loud "claps" perceived by patients and medical staff during endovenous laser ablation (EVLA) are caused by volumetric blood boiling when large vapor-gas bubbles appear and collapse under the action of laser radiation, which is well absorbed in water. Acoustic effects when using lasers in the near infrared range (1.94, 1.

Foaming of blood in endovenous laser treatment.

This work is dedicated to a challenging issue of modern phlebology-establishment of a physical mechanism of the endovenous laser treatment (EVLT) against great saphenous vein incompetence (protuberant varicosities). Using optical and acoustical methods, we have studied the laser-induced formation of microbubbles in an aqueous solution of surface-active substances, serum, and blood directly in patients while conducting EVLT of the great saphenous vein in a clinical setting. We have used lasers with wavelengths 0.