Predictive value of great and small saphenous vein diameters for venous reflux in lower extremity chronic venous insufficiency: A segmental analysis using duplex ultrasonography

Abstract

BACKGROUND: Chronic venous disease is prevalent, particularly in the form of varicose veins, and often involves saphenous vein incompetence. While correlations between vein diameters and reflux presence are established, associations with reflux duration remain underexplored. This study aimed to evaluate the relationship between great and small saphenous vein diameters and reflux durations across lower limb segments in varicose vein patients, and to determine predictive diameter thresholds for reflux. METHODS: In a cross-sectional study with case-control component (2021-2023, Blinded), 753 incompetent veins were analyzed for diameter-reflux correlations using Pearson/Spearman coefficients. Reflux was defined as > 1000 ms at saphenofemoral junction (SFJ) or > 500 ms elsewhere. A subsample of 300 cases was compared to 303 healthy controls for diameter differences via t-tests and receiver operating characteristic (ROC) analyses to identify optimal cut-offs via Youden index. RESULTS: Significant negative correlations were found proximally (SFJ: r = - 0.163, P < 0.05; cranial great saphenous vein GSV: r = - 0.150, P < 0.01) and positive correlation distally (mid-calf GSV: r = 0.130, P < 0.01; caudal small saphenous vein SSV: r = 0.300, P < 0.01). Cases had larger diameters across segments (all P < 0.001). Highest ROC accuracy was for cranial GSV (5 mm cut-off; area under curve AUC = 0.775; accuracy = 72.65%) and cranial SSV (3.6 mm; AUC = 0.779; accuracy = 70.02%); lowest for ankle GSV (2.3 mm; accuracy = 53.31%) and caudal SSV (2.2 mm; accuracy = 59.83%). CONCLUSIONS: Segment-specific diameter-reflux associations highlight the inadequacy of diameter alone for assessing reflux duration, necessitating comprehensive duplex ultrasound evaluation for venous insufficiency management.