Surgical incisions, as used in traditional vein stripping procedures, are not required in endovenous laser treatment. Under ultrasound guidance, a
catheter is introduced percutaneously into the affected vein and advanced to the target segment. A thin laser fiber, typically 2-3 mm in diameter, is then inserted through the catheter and positioned within the vein. In modern laser systems, the laser light is transmitted via the fiber to the catheter tip, where it is delivered either as a ring-shaped or, in some devices, as a radial beam, either continuously or in pulses. Both water molecules and the red blood pigment hemoglobin absorb the laser energy, converting it into heat. The vein wall is heated to approximately 70 °C, causing controlled damage and contraction. The treated vein closes as a result of this thermal injury, preventing pathological venous reflux. Over the following months, the vein hardens, gradually shrinks, and is either absorbed by the body or transformed into connective tissue. Early laser fibers of the so-called “bare-tip” generation delivered energy forward only at the catheter tip, requiring a safety distance of 1-2 cm from the
saphenofemoral junction to avoid damage to the
femoral vein. Later, these were replaced by radial fibers, which emit laser energy evenly in a 360-degree ring around the catheter, either as a single or double ring. This includes systems such as the endo laser vein system, which use radial fibers to uniformly close the vein from the inside. Radial fibers are now standard in endovenous laser therapy, as they provide more uniform energy delivery, improved efficacy, and are associated with fewer side effects such as pain and bruising compared with older bare-tip fibers. These improvements were facilitated not only by the introduction of radial fibers but also by the development of higher-wavelength laser systems, which allow more efficient vein wall heating with less collateral tissue damage. Endovenous thermal ablation, including endovenous laser treatment, is primarily used to treat varicose veins in the major saphenous veins of the legs. These procedures are considered a less invasive alternative to traditional surgical vein stripping, with outcomes that are comparable or, in some aspects, superior. Worldwide, minimally invasive endovenous techniques have largely replaced conventional vein stripping. ==Complications==