The pattern of the distribution of incompetent segments within the great saphenous vein at C2 lower extremity: A report conforming to the 2024 IAC standards and guidelines

ObjectivesTo analyze the distribution of incompetent segments in the great saphenous vein (GSV) in Clinical, Etiological, Anatomical, Pathophysiological (CEAP) classification C2 limbs to provide a reference for appropriate diagnosis and treatment planning.MethodsWe analyzed the distributions of incompetent segments in the GSVs of the C2 lower extremity undergoing duplex ultrasound from September 2017 to December 2023. The examined segments were the saphenofemoral junction (SFJ), GSV at the proximal thigh, GSV at the knee, and GSV below the knee.ResultsA total of 696 lower limbs from 540 patients (male 256, female 440) was analyzed. The mean age was 56 (ranging from 18 to 86), and the mean body mass index (BMI) was 24.0 kg/m². There were 15 types of distribution of incompetent segments within the GSV, with the most common type (32.6%) being reflux from the SFJ to the GSV below the knee. Among the lower limbs with reflux at the SFJ, GSV at the proximal thigh or knee was competent in 10% of lower limbs. In the lower limbs with reflux at the proximal thigh GSV, 26% did not have reflux at the SFJ. The presence of reflux in each segment did not differ by sex, but those with reflux in the below-knee segment were older than those without reflux(<i>p</i> = .003). In each of the three segments above the knee, limbs with reflux had a higher BMI than those without reflux.ConclusionsThe most common distribution type was reflux from the SFJ to the below-knee segment, although this only accounted for about one-third of the cases. Various distribution types of incompetent segments within the GSV were identified, suggesting that reflux testing in multiple segments according to the latest guidelines for ultrasound examination of the lower extremity veins is necessary to avoid unnecessary treatment of segments without reflux.