Male Reproductive Anatomy

Question 1

Describe the structure of the scrotum including its contents and layers.

Answer 1

Cutaneous sac developed from labioscrotal folds and contains the testis, epididymis and the first part of the spermatic cord. It is surrounded by the tunica vaginalis which is a double layered peritoneum membrane (previously processus vaginalis) and this encloses the tunica albuginea. The tunica albuginea organises the testis into lobules by fibrous septae. The dartos muscle lies within the scrotal fascia and is responsible for the rugged appearance of the scrotum.

Question 2

Describe the course of the testi as it descends

Answer 2

Gonads (retroperitoneal) develop within the mesonephric ridge and descend through the abdomen, testes cross the inguinal canal and exit through the anterio-lateral abdominal wall, this explains how it picks up layers of the abdominal wall.

Question 3

What is the blood supply and venous drainage of the testi

Answer 3

Direct branches from the abdominal aorta. Venous drainage of right testi by the right testicular vein into the IVC, the left testi is drained through the left testicular vein into the left renal vein at a much more less acute angle and so is more prone to pressure issues.

Question 4

What are the 3 portions of the epididymis?

Answer 4

Starts with the head consisting of efferent ductules, the body consisting of the convoluted ducts and the tail which is continuous with the vas deferens.

Question 5

Describe the contents of the spermatic cord

Answer 5

Contains structures running to and from the testis. Neurovascular structures include: testicular arteries, cremasteric artery, the artery to the vas deferens, the pampiniform plexus (heat loss) and the genital branch of the genitofemoral nerve. The duct system: vas deferens – a straight muscular tube, lymphatics and processus vaginalis. It runs form the deep inguinal ring (lateral to the inferior epigastric vessels) to the posterior border of the testis via the inguinal canal and superficial inguinal ring.

Question 6

Describe the layers of the spermatic cord and their derivatives

Answer 6

• External spermatic fascia – aponeurosis of the external oblique muscle
• Cremasteric muscle and fascia – internal oblique and transversalis muscle
• Internal spermatic fascia – transversalis fascia

Question 7

What is hydrocoele, haematocoele, varicocoele, spermatocoele and epididmymitis?

Answer 7

Hydrocoele – too much serous fluid produced in tunica vaginalis
Haematocoele – blood in tunica vaginalis from trauma
Varicocoele – varicosities of pampiniform plexus
Spermatocoele – aka epidydimal cyst, retention cyst within the epididymis.
Epididymitis – inflammation of the epididymis

Question 8

How can we use transillumination to discern between different pathologies of the scrotum?

Answer 8

Transillumination of the scrotum – liquid lets light through (except blood) solid does not.
Indirect and direct inguinal hernia – indirect can swell into the scrotum of patent processus vaginalis

Question 9

What is testicular torsion?

Answer 9

Testicular torsion – twisting normally occurs just above upper pole and there is a risk of necrosis of testis. Surgical Emergency

Question 10

What innervates the scrotum?

Answer 10

Lumbar plexus anterior surface and sacral plexus posterior and inferior surfaces

Question 11

What is the lymphatic drainage of the testi and scrotum?

Answer 11

Lymphatic drainage – very important distinction between scrotum and testis
Testis – drains to paraaortic nodes. Scrotum to the superficial inguinal nodes. Reflects their embryology.

Question 12

Describe the course of the vas deferens

Answer 12

Ascends in spermatic cord, transverses inguinal canal, tracks around pelvic side wall, passes between bladder and ureter, form dilated ampulla and opens into the ejaculatory duct.

Question 13

Where do the seminal vesicles lie and how do they reach the urethra?

Answer 13

Lie between at the posterior of the bladder anterior to the rectum. The duct of Seminal Vesicles combines with ampulla of the Vas Deferens to form the ejaculatory duct, this runs through the prostate gland to join the prostatic urethra. Seminal vesicles are a diverticulum of the vas deferens.

Question 14

What is the role of the seminal vesicles?

Answer 14

Not a storage site. They form about 60% of the ejaculate containing fructose and coagulating agent in a thick alkaline fluid.

Question 15

Describe the prostate including its blood supply and lymphatic drainage.

Answer 15

Fibromuscular gland with very important anatomical relationships. Urethra runs right through the centre of the prostate gland. Arterial supply from the internal iliac arteries and venous draining via the prostatic plexus into the internal iliac veins. Lymphatic drainage into the internal iliac and sacral nodes.

Question 16

Describe the anatomical relations the prostate has to other structure in the abdomen

Answer 16

Base – neck of bladder
Apex – urethral sphincter and deep perineal muscles
Muscular anterior surface – urethral spincter
Posterior – ampulla of rectum
Infero-lateral – levator ani

Question 17

What proportion of the ejaculate volume is produced in the prostate and what does it contain?

Answer 17

The prostate secretes about a 1/3 of the ejaculate volume and contains: prostaglandins, proteolytic enzymes and citric acid.

Question 18

What’s more likely to cause urethral obstruction - benign prostate hyperplasia or prostatic malignancies?

Answer 18

Benign Prostatic Hyperplasia
Middle lobule
Obstruction of internal urethral orifice – symptoms dysuria, nocturia, urgency

Prostatic malignancies tend to be on the periphery of the prostate so less likely to be urethral constriction.

Question 19

Where do prostatic malignancies metastasise via?

Answer 19

Metastasis via – internal ilia and sacral nodes and venous routes to internal vertebral plexus to vertebrae and brain.

Question 20

Where are the bulbourethral glands and what is their role?

Answer 20

Located withint the urogential diaphragm and secrete a clear watery secretion which acts to lubricate the urethra.

Question 21

Describe the structure of the penis

Answer 21

Consists of a root, body and glans
Internal structure consists of pair of corpora cavernosa dorsally which are surrounded by the tunica albuginea, during an erection these structure fill with blood making the penis hard. A single corpus spongiosum is situated ventrally and contains the ureathra sits (hence why its called spongy ureathra), during an erection it helps to maintain a patent urethra. Supplied by branches of the interal pudental arteries.

Question 22

What is the blood supply to the penis?

Answer 22

Internal pudental arerty is a branch of the anterior division of the internal iliac artery.

Question 23

What is the perineum?

Answer 23

Perineum area between the anus and scrotum or vulva

Question 24

What is the role of the bulbospongiosum?

Answer 24

Bulbospongiosus helps expel last drops of urine and helps maintain the erection

Question 25

What is the role of the Ischiocavernosus?

Answer 25

Ischiocavernosus compresses veins and helps maintain an erection

Question 26

What are the 4 parts to the male urethra?

Answer 26

Parts of the male urethra

Pre prostatic, Prostatic, Membraous – least distensible and spongy

Question 27

What is oligozoospermia, azzospermia, cryptorchid and orchitis?

Answer 27

Oligozoospermia = low sperm count
Azzospermia = no sperm 
Cryptorchid = undescended tesiticle – high temperature in the body causes issues with spermatogenesis resulting in an increased risk of germ cell tumours.
Orchitis = inflammation of the testis e.g. mumps after puberty.