Male Reproductive Organs Flashcards
What are the internal structures of the male reproductive system
- Vas (ductus) deferens
- Prostatic and intramembranous urethra,
- Prostate,
- Seminal vesicles
Describe features of the scrotum and its skin
- It suspends the testies outside the body for thermoregulation. The scrotal ligament is the remnants of gubernaculum.
The skin is rugose, has no fat and contains the dartos muscle which is supplied by the genitofemoral nerve.
What is the processus vaginialis?
When the testies descend from the posterior abdo wall, each takes ductus deferens, the testicular vessels and a loop of parietal peritoneum called the processus vaginalis. After birth it becomes closed over and forms a potential space called tunica vaginalis
Describe the descent of the testes
The Gubernaculum shrinks to draw the testes down the posterior abdominal wall to the inguinal canal then through the canal during the 8th and 9th month. It therefore brings layers of the abdominal wall with it (except for the transversus abdominis muscle)
What occurs if the proximal part of the tunica vaginalis stays open?
It can lead to an indirect hernia or hydrocele
Describe the layers of the scrotum from superficial to deep.
1) skin,
2) Subcutaneous tissue (dartos muscle and fascia),
3) External spermatic fascia (from fascia of external oblique)
4) Cremasteric muscle and fascia (fibres and fascia of internal oblique),
5) Internal spermatic fascia (transversalis fascia),
6) Tunica Vaginalis (visceral and parietal layers from peritoneum)
What is the blood supply of the scrotum
Anterior 1/3 - External pudendal branches of femoral artery.
Posterior 2/3 - Branches of internal pedendal branch of internal iliac
What is the venous drainage of the scrotum
Anteriorly 1/3 - External pudendal veins to great saphenous vein.
Posteriorly 2/3 - Internal pudendal veins to internal iliac vein.
What is the nerve supply of the scrotum?
Anterior 1/3 - L1 with ilioinguinal and genitofemoral nerve.
Posterior 2/3rds - S2-3 via scrotal branches of perineal branches of the pudendal nerve
What is the lymphatic drainage of the scrotum?
Superficial inguinal nodes
What is hydrocele and how is it treated?
Fluid collecting between the layers of the tunica vaginalis. Aspirated by anterior or lateral approach to avoid posteriorly situated epididymis
What is the tunica albuginea?
- Tough fibrous collagenous layer which maintains internal pressure. Forms mediastinum testis and forms septae.
What is the blood supply of the testis?
- Testicular artery from aorta at L1 and anastomosis with cremasteric artery and artery to ductus deferens)
What is the venous drainage of the testis?
Testicular vein which starts as pampiniform venous plexus
What is the lymphatic drainage and nerve supply of the testis?
Lymph - Drains to para-aortic (LUMBAR) nodes.
Nerve - Sympathetics via lesser splanchnic nerve (T10-11) with referred pain to peri-umbilical.
What is the vas deferens?
Thick-walled tube that carries sperm from testies and epididymis, lies posterior to testies and medial to epididymis.
Describe the travel of the vas deferens
It leaves the scrotum and passes through the abdominal wall within the spermatic cord in the inguinal canal. Lies medial to pelvis vessels before passing antero-medially to ureter. It emerges lateral to the inferior epigastric artery. Lies on lateral wall of pelvis.
Name and describe the three arteries in the spermatic cord
1) Testicular vessels (testicular artery and the pampiniform venous plexus),
2) Artery of ductus deferens (from superior vesical artery)
3) Cremasteric artery and vein (from inferior epigastric artery)
What is the significance of the pampiniform plexus?
It surrounds the testicular artery and aids the convection of heat from the arterial blood
What are the 3 tubular structures present in the spermatic cord?
1) Vas Deferens,
2) Lymphatic vessels
3) Vestige (obliterated tube) of processus vaginalis
What are the two neural structures in the spermatic cord?
1) Genital branch of genitofemoral nerve (supplying cremaster muscle).
2) Sympathetic efferent and afferents which are derived from lesser splanchnic nerve
What are varicoceles?
Dilated tortuous vessels, (pampiniform venous plexus). It can cause a dull, aching or throbbing pain in the testicle and can lead to infertility.
Describe features of the seminal vesicles
The left and right lie just above the prostate between the bladder and rectum. They secrete seminal fluid to nourish sperm.
How do ejaculatory ducts form?
By the union of vas deferens and the duct of the seminal vesicle
