Gross Anatomy - Blood Supply of the Perineal Region

• Arises from the internal iliac artery.
• Leaves the pelvis by way of the greater sciatic foramen between the piriformis and coccygeus and immediately enters the perineum through the lesser sciatic foramen by hooking around the ischial spine.
• Is accompanied by the pudendal nerve during its course.
• Passes along the lateral wall of the ischiorectal fossa in the pudendal canal.
• Gives rise to the following:

1. Inferior rectal artery

• Arises within the pudendal canal, pierces the wall of the pudendal canal, and breaks into several branches, which cross the ischiorectal fossa to muscles and skin around the anal canal.

2. Perineal arteries

• Supply the superficial perineal muscles and give rise to transverse perineal branches and posterior scrotal (or labial) branches.

3. Artery of the bulb

• Arises within the deep perineal space, pierces the perineal membrane, and supplies the bulb of the penis and the bulbourethral glands (in the male) and the vestibular bulbs and the greater vestibular gland (in the female).

4. Urethral artery

• Pierces the perineal membrane, enters the corpus spongiosum of the penis, and continues to the glans penis.

5. Deep arteries of the penis or clitoris

• Are terminal branches of the internal pudendal artery.
• Pierce the perineal membrane, run through the center of the corpus cavernosum of the penis or clitoris, and supply its erectile tissue.

6. Dorsal arteries of the penis or clitoris

• Pierce the perineal membrane and pass through the suspensory ligament of the penis or clitoris.
• Run along its dorsum on each side of the deep dorsal vein and deep to the deep fascia (Buck's fascia) and superficial to the tunica albuginea to supply the glans and prepuce.

• Arises from the femoral artery, emerges through the saphenous ring, and passes medially over the spermatic cord or the round ligament of the uterus to supply the skin above the pubis, penis, and scrotum or labium majus.
  

1. Deep dorsal vein of the penis

• Is an unpaired vein that lies in the dorsal midline deep to the deep (Buck's) fascia and superficial to the tunica albuginea.
• Leaves the perineum through the gap between the arcuate pubic ligament and the transverse perineal ligament and drains into the prostatic and pelvic venous plexuses.

2. Superficial dorsal vein of the penis

• Runs toward the pubic symphysis between the superficial and deep fasciae and terminates in the external (superficial) pudendal veins , which drain into the greater saphenous vein.