Prediction of the effect of saphenous reflux treatment by prior ultrasound probe occlusion

Background: This proof-of-concept study aims to determine whether the haemodynamic effect of saphenous treatment can be predicted using the saphenous occlusion test (SOT). Materials and methods: Fifteen legs (11 patients) with chronic venous disease and 12 legs of healthy controls were assessed using air plethysmography (APG) on a manually operated tilt table transitioning from near-standing to a -40° head-down position and back to control leg filling via APG. Measurements were taken: (i) preoperatively, (ii) during ultrasound-guided compression of the saphenous vein at the thigh (SOT), and (iii) after treatment of the GSV with proximal short-segment endovenous laser ablation (EVLA, not the controls). Clinical CEAP classification: C2 = 2, C3 = 4, C4a = 10, and C6 = 1, median Venous Clinical Severity Score (VCSS) of 5 [2-14]. Median follow 73 [30-89] days. Results: Both, the venous filling index (VFI, mL/s) and venous filling time (VFT90, in seconds) improved significantly with GSV probe compression and EVLA (p < .0005): VFI from baseline 2.6[2-3.3] and predicted 1.2 [1.1-1.6] to postoperative 1.3 [1.1-1.7], VFT90 from baseline 34.7 [23.8-40.1] and predicted 71.4 [46-89.9] to 70.7 [47.9-76]. No significant difference was found between the predicted and actual post-treatment values for VFI (p = .601) or VFT90 (p = 1). Significant difference between controls and patients (VFT90 p < .01, VFI p < .001) was lost after treatment (VFT90 p = .751, VFI p = .826). Conclusions: The haemodynamic effect of saphenous reflux correction can be accurately predicted using the saphenous occlusion test with APG together with orthostatic manoeuvres. This method may serve as a standardised, objective tool to evaluate the need for GSV intervention in patients with visible varicose veins.