Quantitative Evaluation of Therapeutic Efficacy of Endovenous Laser Treatment for Distal Varicose Veins by Tc-99m RBC Venography

Endovenous laser treatment (EVLT) has been shown to be effective for elimination of greater saphenous (GSV) incompetence. While the result of GSV closure has been studied in detail, the effects in distal GSV and its tributaries following EVLT are still not completely understood. In addition, the optimal time for treatment of remaining varicose veins is not established. We evaluated the clinical and radiological changes of distal varicose veins after EVLT and determined the optimal time for additional treatment of distal varicose veins following EVLT by Tc-99m RBC. Forty GSV (30 patients) were treated with 940 nm or 810 nm diode laser at usual energy setting. Clinical and Duplex evaluation were performed at I week, and at various monthly intervals (2-6 months) following the initial treatment. Tc-99m venography was performed as usual protocol at I month and at every 3 months after EVLT. The distal varicose veins were quantified by determining the ratio of mean counts per pixel in the target and background areas and then comparing the pre-EVLT and post-EVLT values. Thirty-eight (95.0%) GSV were closed following EVLT and remained closed at 1-21 months follow-up examination. The reduction rate of distal varicose veins measured by Tc-99m venography was 22.8% at l month, 42.7% at 3 months, 61.5% at 6 months, and 72.4% at 9 months after EVLT. Fifteen legs (37.5%) required additional phlebectomy at 1 to 3 months after EVLT, while the others (62.5%) showed spontaneous regression of distal veins from one month during follow-up period. Therapeutic efficacy of EVLT for distal varicose vein can be well-evaluated quantitatively by Tc-99m RBC venography. Theses results suggest that after EVLT for GSV, the 'wait' policy would be necessary, rather than the 'wasting' of distal veins concurrently with EVLT