by John Mauriello, MD, FACPh
All laser wavelengths are efficacious in endovenous thermal ablation of saphenous veins when used with the optimal energy dosing (LEED) and power.
Short & longer wavelengths
The shorter wavelengths (810, 940, 980), produce a higher number of vessel perforations which lead to a higher incidents of post treatment side effects of pain, bruising and pain medication required. The longer wavelengths (1320, 1470) do not target hemoglobin but have a greater specificity for water that attacks the vein wall, shrinking collagen, similar to segmental radiofrequency ablation (SRFA) procedures.
RFA Statistics
This is probably why there is a much lower rate of pain, bruising and pain medication required with both RF and water-selective laser wavelength (WSLW) technologies. The perfect wavelength is unknown but most companies are now offering the 1470 nm wavelength which speaks for itself. The 1470 nm wavelength, when used with a radial emitting fiber, has been shown to be as gentle and effective as SRFA, while requiring less power (5-6 watts) and energy densities of < 50 J/cm3 compared to other lasers. In fact, it’s not just the wavelength but the combination of a radial-emitting fiber tip with the 1470 nm wavelength that has been shown to be superior to any other laser-fiber system to date. The blunt radial fiber requires only a short (7 or 11 cm) 4 Fr or 6 Fr insertion sheath which decreases insertion time by 50% by avoiding the need to up size to a longer guide wire when using a micropuncture insertion set.
In a prospective randomized split-extremity trial of a 1470 nm laser comparing a bare-tip and radial-tip fiber, patients treated with the radial-tip fiber had statistically less pain, less bruising, and required less pain medication. The bare-tip fiber group had more post-ablation complications, and patients statistically preferred the radial-tip fiber treated extremity.
Summary: The 1470 nm wavelength has evolved to be the wavelength of choice for endovenous laser thermal ablation in the US. When used with a radial-emitting fiber tip, it has be shown to be as effective as other laser systems with much fewer post-treatment side effects, especially when compared to a bare-tip forward-emitting fiber.
References:
- Van den Bos R, Arends L, et al. Endovenous therapies of lower extremity varicosities: A meta-analysis. JVS 2009; 49: 230-239.
- Kabnick L. Venous Laser Updates: New Wavelength or New Fibers? Vascular Disease Management. 2010; 7: 78-81.
- Mauriello J, Sanchez EJ, et al. Radiofrequency ClosureFAST vs Water-Selective Laser Wavelength at 1470 nm for Saphenous Endovenous Thermal Ablation. 23rd Annual congress of the American College of Phlebology. Palm Springs, CA. November 5-8, 2009.
- Mauriello J, Sanchez EJ, et al. Prospective randomized split-extremity trial of a 1470 nm laser comparing a bare-tip and radial-tip fiber for endovenous laser ablation. 24rd Annual Congress of the American College of Phlebology. Orlando, Fl. November 4-7, 2010.
