Laser ablation for varicose veins, while an effective and minimally invasive technique, can cause collateral damage to the surrounding healthy tissue due to the high output power of the laser. It is therefore important to optimize the laser characteristics so that the healthy tissue receives minimal damage. Experimental device for simulation of endovenous laser ablation. Courtesy of Kazan Federal University. Researchers from Kazan Federal University and Ogarev Mordovia State University conducted experiments on endovenous laser ablation of varicose veins in vitro using laser radiation of a solid-state laser based on the crystal LiYF4:Tm, with a wavelength of 1.885 µm and power output of around 3 W. They performed an experimental series with saline solution and red blood cell (RBC) suspension in the venous lumen to identify the impact of a heated carbonized layer precipitated on the fiber end face versus the efficiency of endovenous laser ablation (EVLA). Results of the experiments confirmed that the presence of a heated carbonized layer on the fiber end face increased the efficiency of EVLA. The researchers plan to further refine the experimental process. Specifically, they plan to use radial emitting fibers to minimize the possibility of vein perforations. They also plan to modify the experimental device so as to provide experimental conditions that more closely approximate the conditions of “real-life” endovenous laser ablation. The research was published in Lasers in Medical Science (doi: 10.1007/s10103-016-1877-z).