Objective: Varicocele can be defined as an abnormal tortuosity and dilatation of the veins of the pampiniform plexus. Contradictory results have been obtained from experimental animal models and a few clinical human studies on testicular arterial blood flow in varicocele. The purpose of this study was to determine the changes in testicular arterial blood flow parameters in patients with varicocele. Material and Methods: A total of 62 patients with a clinical diagnosis of left varicocele and a scrotal vein with a diameter of S 3 r mm on color Doppler ultrasonography were included in the study. A total of 44 fertile normal male volunteers served as controls. Results: Median testicular arterial blood flow and median flow rate in milliliters per minute per 100 r g of testicular tissue were found to be significantly decreased in the patient group compared to the control group: blood flow, 1.42 and 2.00 r ml/min; flow rate, 9.63 and 12.35 r ml/min/100 r g, respectively ( p r < r 0...