Radionuclide assessment of penile corporal venous leak using technetium-99m-labeled red blood cells

In an attempt to evaluate penile corporal venous outflow, a method that utilizes intracorporal injection of Tc-RBC was developed and used in 20 patients with erectile dysfunction. Seven patients showed venous leak and 13 had normal venous outflow. Technetium-labeled RBC corporal clearance in the flaccid state and after intracorporal injection of papaverine (30 mg) and regitine (1 mg) were assessed in sequence by two separate injections of 18.5 MBq of Tc-RBC each. The time for 50% corporal clearance (T50%) was determined from the time activity curves obtained in flaccid state and after intracorporal injection of the vasoactive agent. There were no statistically significant differences in T50% measured in the flaccid state between normal venous outflow (202 +/- 139 sec) and venous leak (92 +/- 35 sec, p = 0.1). However, after intracorporal injection of papaverine and regitine a significant increase in the T50% was noted in normal venous outflow (2892 +/- 1899 sec) as compared to venous leak (213 +/- 123 sec, p less than 0.001). The results suggest that measurement of corporal clearance of Tc-RBC after intracorporal injection of papaverine may be a useful method in detecting venous leak, and could be used as a screening test in patients with erectile dysfunction.