Single-Center Study Compares Bare and Radial Fibers in Endovenous Laser Ablation

September 22, 2021—The Society for Vascular Surgery (SVS) announced that findings from a single-center, prospective, randomized trial suggest that endovenous laser ablation (EVLA) using a 1,470-nm laser with a bare fiber provided outcomes in the short term similar to those using a radial fiber. SVS stated that the study provides practitioners with data supporting the use of both modalities in varying clinical situations.

The study was published in Journal of Vascular Surgery: Venous and Lymphatic Disorders by Sunil Rajendran, MS, DNB, MRCSEd, ChM, and Harishankar Ramachandran Nair, MS, MRCSEd, MCh (2021;9:1209-1214). The investigators are from the Department of Vascular and Endovascular Surgery at Starcare Hospital in Calicut, Kerala, India.

SVS noted that endothermal ablation via delivery of either radiofrequency or laser energy to the vein wall has revolutionized the treatment of great saphenous vein (GSV) varicosities over the past 2 decades.

Dr. Nair, the study’s Principal Investigator, commented in the SVS press release, “Studies performed over the past few years using a diode laser showed slightly better occlusion rates and overall success rates compared with radiofrequency ablation, especially for veins with large diameters.

“EVLA, however, is not free of complications, most often including pain and bruising in the lower limb along the ablated vein. One of the main reasons for this has been thought to be vein wall perforation from the laser heat, the incidence of which is greater with conventional bare fibers. Significant data comparing use of bare fibers and radial fibers with the 1,470-nm diode laser are lacking. The aim of our trial was to directly compare these modalities, specifically looking at Venous Clinical Severity score (VCSS).”

In the study, 86 patients with primary GSV varices were randomized into treatment with bare fiber (n = 43) versus radial fiber (n = 46) from January to December 2019.

SVS summarized the study and compared bare versus radial fiber as follows:

• Clinical data between the two groups included vein size (5.74 ± 1.7 mm vs 5.24 ± 1.0 mm; P = .31) and VCSS (7.7 vs 6.8; P = .27).
• At 1 month after treatment, no recanalization of the treated GSV was detected by ultrasound.
• Postprocedural pain was assessed by an analog scale (1 to 10) at 8 hours (2.77 vs 2.7; P = .83) and 1 week (2.81 vs 2.74; P =.87)
• There was notable improvement in VCSS scores postprocedure for both groups (from 7.7 to 2.49 ±1.2 vs from 6.8 to 3.27 ± 2.2; P = .054).

As reported in the SVS press release, the investigators concluded that there were no significant differences in postoperative pain or improvement in the VCSS at 30 days between the two modalities. Furthermore, bare fibers can be effectively used at lower power (7W) and similar linear endovenous energy density compared with radial fibers, and they can be a useful tool for difficult EVLA.

Dr. Nair stated in the announcement, “The radial fiber and longer wavelength (1,470-nm) laser were introduced to mitigate the local complications of the conventional bare fibers, and their use has been reported to result in less recurrence. Very few studies, however, have compared outcomes such as postoperative pain, ecchymosis, and recurrence in bare fibers versus radial fibers.

“Despite reported advantages of the radial fibers, some disadvantages do exist compared with the bare fibers for EVLA. The optical fiber of the radial fiber has a larger outer diameter of 1.85 mm compared with the smaller 600-um bare fiber, making the former stiffer. This can make it more difficult to track a radial fiber through tortuous or aneurysmal veins.”