Two Circulatory Routes Within the Human Corpus Cavernosum Penis: A Scanning Electron Microscopic Study of Corrosion Casts

Abstract

The microvascular architecture of the human corpus cavernosum penis was studied by scanning electron microscopy of vascular corrosion casts. The corpus cavernosum was supplied by the penile deep artery. It gave off branches to become either arteries distributed within the corpus cavernosum or those directly supplying the corpus spongiosum urethrae. The former arteries further divided into small arteries which fell into two categories: 1) arteries breaking up into capillaries, and 2) arteries draining directly into the cavernous sinuses. The capillaries were collected into venular networks just beneath the tunica albuginea (the subalbugineal venular plexus), while the cavernous sinuses were collected into venules at the periphery of the corpus cavernosum. These postcavernous venules also received venules from the subalbugineal venular plexus, and left the corpus cavernosum. Thus, two circulatory routes are evident within the corpus cavernosum. These findings suggested that the penile erectile cycle is controlled by hemodynamic changes between these two routes within the corpus cavernosum.

Pre-penile arteries are dominant in the regulation of penile vascular resistance in the rat

“…Concepts widely accepted in vascular physiology suggest that small arteries with diameters smaller than 100 mm are normally considered to be the major site of resistance. 11 Applying that concept to the penis suggests that the helicine arterioles, whose diameter is 50 ± 300 mm, 3,6 is a major contributor to vascular resistance. In fact, our results demonstrate that the contribution of the small arteries within the penis is less than 20% of the total resistance.…”

Penile Arteries and Erection

“…The internal pudendal artery branches off the hypogastric artery and splits into the bulbourethral, dorsal, and cavernosal arteries, where the bulbourethral artery supplies the urethra and the glans while the cavernosal arteries lie in the middle of the corporal bodies and give rise to the helicine resistance arteries which feed the individual trabeculae. Scanning electron microscopy of cast of the penile microcirculation has revealed that the helicine resistance arteries open directly into the lacunar spaces [8, 9]and application of power Doppler sonography to male potent subjects has shown that helicine arteries are activated during penile tumescence and continue to supply blood to the corpora cavernosa also during maximum penile rigidity [10]. However, another route, which probably is of importance during the flaccid state, is from the cavernous artery to capillary networks collected into the venular plexus just beneath the tunica albugenia [9].…”

“…Scanning electron microscopy of cast of the penile microcirculation has revealed that the helicine resistance arteries open directly into the lacunar spaces [8, 9]and application of power Doppler sonography to male potent subjects has shown that helicine arteries are activated during penile tumescence and continue to supply blood to the corpora cavernosa also during maximum penile rigidity [10]. However, another route, which probably is of importance during the flaccid state, is from the cavernous artery to capillary networks collected into the venular plexus just beneath the tunica albugenia [9]. The paired dorsal penile arteries supply superficial structures in the penis and also the corpora cavernosa via circumflex arteries.…”

‘Venous lakes’ — a corrosion cast scanning electron microscopy study of regular and myomatous human uterine blood vessels

“…The application of corrosion casting and SEM to autopsy material bears a risk of poor tissue preservation. Only single papers report successful casting of such material [1,18]. This obviously limits corrosion casting studies of human tissues and organs.…”