Quantitative Venous Severity Scoring Using the Venous Arterial Flow Index by Duplex Sonography

Abstract

background. Volume flow, as the product of the mean blood flow velocity by the cross sectional area, means an interesting hemodynamic pattern that can be calculated by duplex. objective. To quantify the severity of venous insufficiency using the correlation between the volume flow in the common femoral vein (VFV) and artery (VFA), called the venous arterial flow index (VAFI). methods. A total of 163 consecutive patients were included: 46 patients with postthrombotic syndrome (PTS, group 1), 38 patients with complete varicosity of the greater saphenous vein (group 2), 40 patients with only segmental or truncal varicosity (group 3), and 39 patients with competent veins (group 4). Under standardized conditions, duplex sonography was performed to calculate volume flow in the common femoral vein and ar-tery as a product of mean blood flow velocity ( v m ) and precise diameter ( d ϭ 2 r ) of the vessel due to the formula VF ϭ v m ϫ r 2 (L/min). Division of the venous and arterial volume flow data calculated the VAFI. results. Significant differentiation of VFV ( P Ͻ .001) and VAFI ( P Ͻ .0001) between varicose veins and healthy limbs were found. In PTS the mean VFV was 0.50 L/min and the mean VAFI was 1.465. In the complete varicosity group, mean VFV was 0.46 L/min and mean VAFI was 1.48. In group 3, the mean VFV was 0.41 L/min and the mean VAFI was 1.31. In healthy persons, mean VFV was 0.36 L/min and mean VAFI was 0.87. conclusion. The VAFI can be used to quantify the hemodynamic severity in venous insufficiency.

Venoarterial Flow Index Steadily Improves After Endovenous Laser Treatment of the Great Saphenous Vein

“…Duplex ultrasound allows the direct assessment of hemodynamic alterations caused by venous insufficiency in a quantitative manner, 3,4 but reflux velocity and duration measurements are difficult to standardize because several factors, such as participant cooperation during the Valsalva maneuver in the supine position and muscle relaxation in the standing position, influence those parameters. A novel approach to evaluate hemodynamics to score the severity of venous diseases using duplex ultrasound is the venous arterial flow index (VAFI) established by Kahle and colleagues 5 . VAFI indicates the ratio of mean venous and arterial flow volume as determined in the common femoral vein and artery on corresponding levels.…”

Efficacy of Sclerotherapy in Varicose Veins-A Prospective, Blinded, Placebo-Controlled Study

“…Both venous flow volume and arterial flow volume have been measured in the supine position with a slight elevation of the upper body while the patient was relaxed and breathing calmly. In previous investigations we found the venoarterial flow index, always measured in supine position, to be a suitable pattern to quantify the hemodynamic severity of venous insufficiency 9–14,26,27 . In competent veins, the venoarterial flow index was found to be lower than 1.0 in contrast to venous insufficiency with values of the venoarterial flow index higher than 1.2 and more severe forms of venous incompetence where the venoarterial flow index was found to be higher than 1.3.…”

“…In other studies venoarterial flow index was found to be reproducible and reliable during a time course of 40 min (five measurements every 10 min) and within 3 days at different day times 12,13 . In varicose veins a significant decrease of the venoarterial flow index to levels as they were found in competent veins could be shown according to venous surgery 14 …”

“…In previous studies venoarterial flow index was found significantly increased in venous insufficiency. Moreover, venoarterial flow index differed significantly between patients with different clinical grade of the disease 9,10 …”

Letter to the Editor and Response

“…I have read with interest the article of Dr. Kahle and collaborators in the October 2002 issue of Dermatologic Surgery 1 . Although I consider it very important to find an objective way to measure the severity of chronic venous insufficiency (CVI), I have some observations on the methods that the authors have used.…”