Low Tube Voltage Indirect CT Venography (CTV) in Lower limbs:A Potential Guidance for Varicose Vein in Preoperative Assessment

Purpose: To investigate the feasibility of low tube voltage indirect CT venography (CTV) in superficial venous system in varicose veins (VV) of lower limbs. Materials and Methods: This prospective study has been approved by the hospital institutional review board. Fifty-five consecutively patients (F/M, 23/32, age range 15-77 years) suspicious of varicose veins were recruited in this study. All the patients were performed CT venography (CTV) in lower limbs. The signal intensity (SI) of great saphenous vein (GSV) and varicose vein (VV) was measured, and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective image quality of MPR and 3D volume rendering (VR) were assessed by two experienced radiologists using a 3-point scale. Perforator veins larger than 5 mm in the VV were marked. The radiation doses were recorded. Results: Forty-four patients were diagnosed as VV, including 31 unilateral and 13 bilateral VV, while 2 patients with arteriovenous fistula, 3 hypovenosity and 6 deep venous thrombosis. All GSVs in 44 patients were demonstrated the entire length in Low tube voltage CTV. There is no statistical significance in quantitative indexes between the proximal point in GSV and VV, with the mean SI, SNR and CNR (122 ±16.4 Versus (125.9±23.6)HU), (9.62 ±2.71 Versus 9.91 ±3.12), (4.0 ±2.39 Versus 4.36 ±2.81), respectively. For subjective image quality, 35 (79.5%) were excellent, 8 (18.2%) fair and 1 (2.3%) poor. Twenty-two perforator veins were detected in 15 patients, and the mean diameter of perforator veins marked by CTV was 3.21 ±0.87 mm, which were ligated during the surgery thereafter. The mean radiation dose was (804.7 ±96.7)mGy.cm. Conclusions: Low tube voltage indirect CT venography with iterative reconstruction accommodates available image quality for diagnosis of varicose vein in lower extremities, and provides the road map in preoperative assessment, especially for deep-seated perforating veins, which demonstrates the potential ability to navigate the varicose vein surgery.