Editors: Graham, Sam D.; Keane, Thomas E.; Glenn, James F.Title: Glenn's Urologic Surgery, 6th EditionCopyright ©2004 Lippincott Williams & Wilkins> Table of Contents > Section VIII - Penis/Scrotum > AnatomyAnatomySam D. Graham Jr.The penis is composed of three columnar bodies, a pair of which are larger, dorsally located, and extend the length of the penis (Figure SVIII-1). These two columnar bodies contain cavernosal vascular tissue and are called the corpora cavernosa. Proximally the corpora cavernosa taper to form the crus and are attached to the pubic arch. Each corpora is closely applied to the other, separated only by a septum, for most of the distal penis. The corpora cavernosus is supported at its base by the ischiocavernosus muscles which arise from the inner surface of the ischial tuberosity and are innervated by the perineal nerves.

FIG. SVIII-1. Anatomy of the three corporal bodies comprising the penis.The third columnar body, the corpora spongiosa, contains the urethra and the distal end is bulbous forming the glans penis. The corpora spongiosa is attached proximally to the perineal membrane and at the most proximal portion is larger forming the bulb.Each of the corporal bodies is encased in its own tunica albugnea and the 3 corporal bodies are surrounded by Buck's fascia which is a continuation of Colle's fascia. (Figure SVIII-2). Buck's fascia is attached posteriorly to the urogenital diaphragm and anteriorly forms the suspensory ligament. There is little vascular communication between the corpora cavernosa and the corpora spongiosa. There is, however, vascular communication between the two corpora cavernosa via pectinoform septa in the distal corpora.

FIG. SVIII-2. Cross-section of the penis demonstrating fascial layers as well as vascular and neuroanatomyVASCULAR ANATOMYThe superficial penile artery lie between the superficial and Buck's fascia and originates from the external pudendal artery which in turn is a branch of the femoral P.532

artery. This artery, along with a corresponding vein supplies the penile skin and is located between the superficial penile fascia and Buck's fascia. The deep arterial supply arises from the internal iliac artery which initially branches into the internal pudendal artery and then into the penile artery. As the penile artery exits the urogenital diaphragm it branches into the bulbourethral, cavernosus, and urethral artery. The cavernosus artery is the direct supply of the corpora cavernosa. The penile artery continues along the corpora cavernosa as the dorsal artery.The corpora spongiosa is supplied by the bulbourethral artery proximally, circumflex arteries from the dorsal artery along its shaft. The glans is supplied by the dorsal artery. The dorsal artery, deep dorsal vein, and the dorsal nerve are enclosed within Buck's fascia.The superficial penile vein drains into the external pudendal vein. The circumflex and deep dorsal vein drain into the Plexus of Santorini as do the crural and cavernosal veins (Figure SVIII-3).

FIG. SVIII-3. Venous drainage of the penis.LYMPHATIC ANATOMYThe lymphatics of the penile skin drain into the superficial inguinal and subinguinal lymph nodes. The lymphatics of the glans penis empty into the subinguinal and external iliac nodes. The deep lymphatics drain into the hypogastric and common iliac nodes.