Testicular Blood Flow in Man Measured with Venous Occlusion Plethysmography and Xenon

Abstract

The interpretation of results obtained when using a clearance technique with radioactive tracers, in measuring the blood flow through an organ, remains a matter of dispute. A comparative study therefore was made in 6 men in whom the testicular blood flow was measured intraoperatively both by means of venous occlusion plethysmography and a Xenon wash-out technique with intratesticular injection. Plethysmography gives the total blood flow in the testis, epididymis, and the tunics while the Xenon technique measures the blood flow in the testis alone. Previous studies in rams have shown the same blood flow in the testis as in the epididymis expressed in ml/100 g tissue/min. Assuming that the ratio is the same in the human male, the plethysmographic flow of the testis could be calculated. The plethysmographic flow calculated in this way was 9 ml/100 g/min. Compared with various techniques of evaluating the Xenon activity curves, this is in agreement with the flow calculated according to Zierler or from the slow component of the Xenon disappearance curve. The possible influence of a counter current exchange on the results obtained by the Xenon clearance technique, is discussed.