Clinical determinants of ultrasound-guided sclerotherapy. Part II: In search of the ideal injectate volume

Ablation of the incompetent saphenous vein may be accomplished by either surgical extirpation or ultrasound-guided sclerotherapy (UGS). Procedural guidelines for optimizing UGS outcome have yet to be established for this relatively new procedure.

To compare the effect of 1 vs 2 mL UGS sclerosant injectate volumes (SIV) on immediate vasospasm and later clinical outcome after UGS.

UGS was performed on 56 patients with Class C2-4EPASPR venous insufficiency and duplex-confirmed saphenous junctional incompetence using 3% sodium tetradecyl sulphate (STS) and Class II compression. Group 1 received 1 mL SIV, and group 2 received 2 mL SIV. Treatment endpoint for both groups was persistent vasospasm observed on duplex imaging (15 mL maximum), with clinical and duplex follow-up at 2 weeks, 6 months, and 12 months.

The number of injections per treatment to achieve vasospasm (vasospastic dose) was unaffected by doubling the SIV. Group 2 had a higher recanalization rate than group 1. Several patients in group 2 experienced a transient febrile response shortly after treatment.

Using our UGS protocol to treat saphenous junctional incompetence, 2 mL SIV was less effective than 1 mL SIV, and was associated a minor adverse effect. The larger SIV did not induce more rapid vasospasm, and therefore did not lead to a reduction in the number of injections per treatment. The maximum safe STS dose/session is unknown, and deserves scientific study.