Recording of penile tumescence and rigidity in impotence.

A new method of continuous and simultaneous recording of nocturnal penile tumescence and rigidity was used in 70 men (38 normal and 32 impotent). The RigiScan test provided several findings concerning nocturnal penile erection in impotent men. Of 32 impotent men, 9(28.1%) had normal patterns, 2(6.3%) had normal penile tumescence without rigidity, and 6(18.7%) had a dissociation of rigidity between the tip and base of the penis. Of 9 patients (28.1%) with a shortened duration of erection in the RigiScan test, 6 had undergone cavernosography, and all were proved to have venous incompetence. Low amplitude of rigidity (6.3%) and flat tracing (12.5%) were also seen. The RigiScan test is superior to other available methods of assessing erectile response. It produces an objective, accurate record of rigidity as well as tumescence, thus aiding in differentiating psychogenic from organic impotence.