[Basic and clinical research of impotence--its present situation and problems involved].

From detailed investigation of the vascular structure of the penis, it has been proposed that there exists a valvular structure, consisting of smooth muscle, located at a point immediately before the helicine artery, bifurcated from the deep artery, opens to the cavernous sinuses, an area where autonomic nerves are densely distributed, participating in opening and closing the valve. On the other hand, there is said to be no valvular structure in the vein outflowing from the cavernous sinuses, and blood flows into the dorsal penile vein by penetrating the albuginea obliquely or vertically after running parallel in the region immediately below the albuginea. It is considered that, when the valve of the helicine artery opens, blood flows into the cavernous sinuses, expanding them, and as a result the outflowing vein is compressed between the sinuses and the albuginea, or the albuginea itself, acting like a valve and therefore assuming an important function in maintaining erection by disturbing the reflux of blood flow. It is also presumed that the contracting of ishiocavernous muscle plays a part in developing the rigidity of the penis. It is considered, moreover, that the trabecula of the cavernous body consisting of smooth muscle also plays a part in the promotion and disappearance of erection. It is very important to run functional tests of erection when diagnosing impotence, and today many tests are available for differential diagnosis; including papaverine test, dynamic cavernosometry and cavernosography. As for therapy, treatments involving vasoactive agent infusion, such as papaverine or prostaglandin E1 into the cavernous body, have become common. For cases with venous impotence, ligation of the penile deep vein and crus of the penile cavernous body have come to be attempted. Furthermore, revascularization of penile artery can be performed to treat arterial impotence. For cases in whom these methods are not effective, implantation of various penile prostheses into the penis has been shown to be successful.