We have reported that the extent of the VR is a determinant factor for the hemodynamic and clinical efficiency of ASVAL [1]. The extent of the VR was evaluated according to the number of zones to be treated (NZT) by phlebectomy, with each limb divided into up to 32 zones in the preoperative clinical mapping (Fig. 14.3). Each limb was divided into four surface areas (anterior, posterior, lateral, and medial), and then each surface area was divided into eight zones: the thigh into three zones (the upper third, middle third, and lower third), the calf into three zones (the upper third, middle third, and lower third), plus one zone for the knee, and one zone for the foot. This arrangement reflects our clinical examination technique, in which we examine each lower limb in a standing position, from the front, from the back, and from each of its profiles (medial and lateral). We observed a significant linear trend between the outcomes after ASVAL and the NZT: when the NZT was above seven, an abolition of the saphenous reflux was 6.81 times more likely obtained (P = 0.037) and a symptom relief 2.91 times more likely achieved (P = 0.004).

During the ultrasound duplex assessment with the patient standing upright, the test of reversibility (TR) is considered as positive if the reflux of the SV is completely abolished by the compression of the varicose tributary with a finger at the moment of the sudden release of manual compression on the calf. We have reported the value of the TR in a study on 293 lower limbs: the positive predictive value of the TR for the abolition of reflux of the GSV was 95.7% and 94.7% at 1 and 2 years of follow-up [8]. On the other hand, the negative predictive value was weak at 36% and 14% at 1 and 2 years of follow-up, and the preoperative positivity of the TR did not have any correlation with the symptom relief or the cosmetic improvement. It means that if the positivity of the RT is a major criterion for the preservation of the SV, its negativity is not enough at the opposite to ablate the SV. Indeed, we have observed that even when the RT was negative, an abolition of the saphenous reflux , a cosmetic improvement, and/or a symptom relief can be achieved, probably because the RT is not technically feasible in the presence of multiple varicose tributaries.

Biemans et al. [3] have reported a PREST prediction model including CEAP classification, number of refluxing segments, GSV diameter (above the tributary), and reflux elimination test result, in order to give a preoperative score that correlates with a probability of restoring GSV competence. For example, for patients with GSV reflux in one segment (3 points), C2 (3 points), positive reflux elimination test result (2 points), and GSV diameter of 5 mm (6 points), the model can predict that phlebectomy will be effective in 90% (total of 14 points).