Papaverine hydrochloride was administered to the cavernous body of the penis in a total of 262 patients who were diagnosed as impotent at our Reproduction Center, Toho University, during the 5 years' period from 1984 to 1988. The condition of erection was accurately recorded by the use of both a mercury strain gauge and rubber strain gauge to classify the erection curve, and papaverine hydrochloride outflow into the peripheral blood was concurrently measured in some of the cases in order to assess its relation with the erection curve pattern.
As for the concentration of papaverine hydrochloride in the peripheral blood, it was found that the better the state of erection, the smaller the outflow of peripheral blood. An assessment of the relationship of the concentration of papaverine hydrochloride with the classification of erection pattern showed that the amount of outflow was smaller in the N type (normal) pattern and that the amount of outflow was increasingly larger in the following order: A type (arterial), N′ type (arterial and venous) and V type (venous).
The distribution of the erection curve patterns, in the 262 cases was: N type, 45%; A type, 10%; N′ type, 22.5%; and V type, 22.5%.
From the above findings, it is presumed that classification of erection curve pattern under papaverine hydrochloride loading is useful for the differentiation of vascular impotence, particularly for the diagnosis of disorders in the outflow system.