Phlebology

Technology

• Endovenous laser treatment (EVLT) is a modern, minimally invasive method for treating pathological veins.

  A laser fiber is inserted into the affected vein, where controlled laser radiation induces a thermal effect on the vein wall. This initiates a biological response that leads to fibrotic occlusion and the gradual replacement of the diseased vein with connective tissue.

   

  A critical factor in EVLT efficacy is the efficient delivery of heat and convection within the vessel. This is especially effective when using 1.94 μm laser radiation, which offers high absorption in water-rich tissues. As a result, thermal energy is delivered more precisely at lower power levels, reducing collateral damage while ensuring reliable vein closure.

   

  To further elevate procedural safety and control, the VTLase system is equipped with the FiberDamage Sensor — an advanced feature that continuously monitors the condition of the radial fiber during treatment. If fiber damage is detected, the system immediately halts laser emission, preventing harm to surrounding tissues and ensuring maximum safety and operational reliability.

• Clinical comparison of varicose vein treatments

  Parameters	Phleboctomy	Sclerotherapy	Radiofrequency obliteration	EVLT
  Treatment efficiency	High	Mid	High	High
  Effectiveness for large-diameter veins	High	Low	High	High
  Level of invasiveness	High	Low	Low	Low
  Postoperative pain intensity	High	Low	High	Low
  Cosmetic outcomes	Low	High	Mid	High
  Requirement for hospitalization	Yes	No	No	No
  Duration of postoperative pain, days	>10	0	3-5	0-1
  Duration of analgesic use, days	>5	0	1	0
  Extent of paravasal tissue damage	-	-	High	Low
  Applicability for trophic ulcer cases	No	No	Yes	Yes
  Duration of the operation	≥1 hour	10 min	20-30 min	10-20 min
  Length of disability period	2-4 weeks	0 day	1-5 day	0 day

• Evolution of EVLT laser technologies

   

  Over the years, Endovenous Laser Treatment (EVLT) has evolved significantly with advances in laser wavelength technology, directly impacting the efficacy, safety, and patient experience of the procedure. The evolution of EVLT lasers can be categorized into three major stages:

   

  "Hemoglobin " lasers (0.98 μm) — outdated technology

  Early EVLT systems utilized 0.98 μm wavelength lasers, which primarily targeted hemoglobin within the blood. While initially effective, these systems had several drawbacks:

   

  • Higher thermal injury to surrounding tissues
  • Increased postoperative pain and bruising
  • Greater risk of complications such as nerve damage

   

  This technology is now considered outdated due to the availability of more tissue-selective wavelengths that offer improved clinical outcomes.

   

  "Water " lasers (1.47–1.55 μm) — the current Gold Standard in EVLT

  The introduction of water-absorbing diode lasers in the 1.47–1.55 μm wavelength range marked a major advancement in endovenous laser therapy. Among them, 1.55 μm lasers are now widely recognized as the global gold standard for EVLT procedures due to their proven safety and efficacy.

  • Water, the primary chromophore in vein walls, absorbs these wavelengths with high efficiency, enabling controlled, localized thermal effects.

  • This results in reduced thermal spread, lower postoperative pain, improved cosmetic outcomes, and greater procedural precision.

   

  "Water " lasers (1.94 μm) — New Generation technology

  The latest innovation in EVLT lasers is the use of 1.94 μm wavelength systems, representing the new generation of endovenous treatment:

  • Exceptional water absorption at 1.94 μm enables highly localized thermal damage to the vein wall, maximizing treatment precision.

  • Effective vein closure at lower energy levels reduces collateral tissue damage and postoperative discomfort.

  • Improved heat transfer and convection promote safer, more efficient energy delivery, contributing to faster recovery and better cosmetic outcomes.

   

  The absorption coefficient of water increases sharply with wavelength, peaking at 1.94 μm. This high absorption improves energy confinement to the target tissue, making EVLT with 1.94 μm lasers more controlled and less invasive than earlier-generation systems (e.g., 1.47 μm or 1.06 μm).

   

  1.94 μm laser technology sets a new benchmark in endovenous therapy—delivering maximum precision with minimal thermal risk, and redefining the standards of care in modern phlebology. 



Dependence of radiation absorption coefficient on wavelength

Roggan A., Bindig U., Wäsche W., & Zgoda F. (2003). Action mechanisms of laser radiation in biological tissues, Applied Laser Medicine. Ch. I-3.1. Pg. 87.