RP-30A: new tracer for detection of changes in testicular blood flow in rat torsion model.

RP-30A is a radioactive tracer being evaluated for the detection of regional myocardial blood flow. This study compares RP-30A to technetium 99m pertechnetate as radioactive tracers for the detection of testicular blood flow changes in early testicular torsion. The left testis of adult male Sprague-Dawley rats was subjected to either thirty or sixty minutes of 720 degrees torsion. Injections of RP-30A or 99mTc-pertechnetate followed by sacrifice and scintillation counting of the testes was performed. No significant difference was detected between the torted testes and the right control testes in both groups receiving 99mTc-pertechnetate and the thirty-minute group receiving RP-30A. The torted testes of the sixty-minute group receiving RP-30A revealed a significant difference (decrease) in uptake indicating that RP-30A may be a more sensitive tracer in detecting testicular blood flow changes in early testicular torsion.