St A - Male Reproductive Organs

Question 1

What are the internal structures of the male reproductive system

Answer 1

• Vas (ductus) deferens
• Prostatic and intramembranous urethra,
• Prostate,
• Seminal vesicles

Question 2

Describe features of the scrotum and its skin

Answer 2

• 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.

Question 3

What is the processus vaginialis?

Answer 3

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

Question 4

Describe the descent of the testes

Answer 4

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)

Question 5

What occurs if the proximal part of the tunica vaginalis stays open?

Answer 5

It can lead to an indirect hernia or hydrocele

Question 6

Describe the layers of the scrotum from superficial to deep.

Answer 6

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)

Question 7

What is the blood supply of the scrotum

Answer 7

Anterior 1/3 - External pudendal branches of femoral artery.

Posterior 2/3 - Branches of internal pedendal branch of internal iliac

Question 8

What is the venous drainage of the scrotum

Answer 8

Anteriorly 1/3 - External pudendal veins to great saphenous vein.
Posteriorly 2/3 - Internal pudendal veins to internal iliac vein.

Question 9

What is the nerve supply of the scrotum?

Answer 9

Anterior 1/3 - L1 with ilioinguinal and genitofemoral nerve.

Posterior 2/3rds - S2-3 via scrotal branches of perineal branches of the pudendal nerve

Question 10

What is the lymphatic drainage of the scrotum?

Answer 10

Superficial inguinal nodes

Question 11

What is hydrocele and how is it treated?

Answer 11

Fluid collecting between the layers of the tunica vaginalis. Aspirated by anterior or lateral approach to avoid posteriorly situated epididymis

Question 12

What is the tunica albuginea?

Answer 12

• Tough fibrous collagenous layer which maintains internal pressure. Forms mediastinum testis and forms septae.

Question 13

What is the blood supply of the testis?

Answer 13

• Testicular artery from aorta at L1 and anastomosis with cremasteric artery and artery to ductus deferens)

Question 14

What is the venous drainage of the testis?

Answer 14

Testicular vein which starts as pampiniform venous plexus

Question 15

What is the lymphatic drainage and nerve supply of the testis?

Answer 15

Lymph - Drains to para-aortic (LUMBAR) nodes.

Nerve - Sympathetics via lesser splanchnic nerve (T10-11) with referred pain to peri-umbilical.

Question 16

What is the vas deferens?

Answer 16

Thick-walled tube that carries sperm from testies and epididymis, lies posterior to testies and medial to epididymis.

Question 17

Describe the travel of the vas deferens

Answer 17

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.

Question 18

Name and describe the three arteries in the spermatic cord

Answer 18

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)

Question 19

What is the significance of the pampiniform plexus?

Answer 19

It surrounds the testicular artery and aids the convection of heat from the arterial blood

Question 20

What are the 3 tubular structures present in the spermatic cord?

Answer 20

1) Vas Deferens,
2) Lymphatic vessels
3) Vestige (obliterated tube) of processus vaginalis

Question 21

What are the two neural structures in the spermatic cord?

Answer 21

1) Genital branch of genitofemoral nerve (supplying cremaster muscle).
2) Sympathetic efferent and afferents which are derived from lesser splanchnic nerve

Question 22

What are varicoceles?

Answer 22

Dilated tortuous vessels, (pampiniform venous plexus). It can cause a dull, aching or throbbing pain in the testicle and can lead to infertility.

Question 23

Describe features of the seminal vesicles

Answer 23

The left and right lie just above the prostate between the bladder and rectum. They secrete seminal fluid to nourish sperm.

Question 24

How do ejaculatory ducts form?

Answer 24

By the union of vas deferens and the duct of the seminal vesicle

Question 25

What is the prostate and its functions

Answer 25

it is a fibromuscular organ that surrounds the urethra. At the time of ejaculation it secretes prostaglandins, acid phosphatase and proteolytic enzymes. It also secretes prostate-specific antigen (PSA)

Question 26

Describe the features of the prostatic urethra

Answer 26

• Contains the opening of prostatic ducts on either side of the seminal colliculus. Has prostatic utricle which opens into centre of seminal colliculus, on either side are the opening of the ejaculatory ducts

Question 27

Describe the lobes of the prostate

Answer 27

• Median lobe (between urethra and ejaculatory ducts),
• Posterior lobe (behind urethra),
• Anterior lobe (anterior to urethra and has no glandular tube.
• Left and right lobe on both sides of urethra.

Question 28

What are MacNeal’s Zones?

Answer 28

Transitional zone which is anterior to ejaculatory ducts (BPH).

• Central zones which is posterior to transitional zone and contains ejaculatory ducts.
• Peripheral zone (around transitional and central zones - common site for tumours)

Question 29

Describe the blood supply of the prostate

Answer 29

Arterial supply via inferior vesical artery.
Prostatic venous plexus drains to internal iliac vein (it has connections with vertebral veins - significant in metastasis)