Measurement of testicular blood flow at orchiopexy with a solid state laser

We have evaluated the solid state laser as a means of determining testicular blood flow at operation. A solid state laser was used to measure blood flow before mobilization of cryptorchid testes, and subsequently after mobilization and placement within a subcutaneous scrotal pouch. Testicular volume was calculated. The median blood flow (ml/100 gm/min) before mobilization was 8.96 (range, 3.43 to 27.2). After mobilization a modest rise to 9.39 (range, 1.82 to 23.75) occurred, which was not statistically significant. However, heterogeneity existed in the response; 11 testes showed a median fall of 8.07 (range, 1.59 to 15.36), which was significant compared to the initial value; 16 testes showed a variable degree of hyperemia with a rise of 2.57 (range, 0.1 to 12.7), which was also significant compared to the initial value; two testes showed no change. The testes that showed a fall in blood flow were all high abdominal testes, which required the most mobilization. The mean testicular volume was 0.38 cc (SEM, 0.03 cc). No difference was noted in size between testes with a net rise in blood flow (mean volume, 0.38 cc) and testes with a net fall in blood flow (mean volume, 0.375 cc). No relationship was noted between testicular size and blood flow. We conclude that the solid state laser is a simple means of measuring testicular blood flow at orchiopexy and may provide a method of deciding which testes should undergo microvascular replantation on the basis of inadequate perfusion per-operatively.