7 - Repro - Male repro system Flashcards
Name the 2 muscles which lie in the scrotum:
- Cremaster muscle
- Dartos muscle
What is the Cremasteric reflex, and what does it test?
- Lightly stroke superior medial thigh in downward direction, should cause contraction of cremaster = retraction of testicle
- Tests L1/2 (Ilioinguinal + Genital branch of Genitofemoral nerves)
Name the muscle which causes the scrotum to wrinkle in the cold, and explain why this is important:
Dartos muscle
Decreases SA, minimising heat loss, to maintain optimum temperature for sperm.
What is the tunica vaginalis?
Serous pouch which covers the testes. Derived from the processus vaginalis of the peritoneum.
To which lymph nodes does the scrotum drain to?
Superficial inguinal nodes
Name the fibrous covering of the testes:
Tunica albuginea
What is the arterial supply to the testes?
Testicular arteries (from abdominal aorta ~ L1/2)
What is the venous drainage of the testes?
Testicular veins from the Pampiniform plexus in scrotum:
Left testicular vein - drains into left renal vein
Right testicular vein - drains into IVC
To which lymph nodes do the testes drain to?
- Paired lumbar nodes and para-aortic nodes @ L1 level (retroperitoneal)
Think of origin of testes
Name the fascial layers of the spermatic cord, and where they are derived from:
1) External spermatic fascia - from aponeurosis of external oblique
2) Cremasteric muscle + fascia - from internal oblique
3) Internal spermatic fascia - from transversalis fascia
Describe the location of the deep inguinal ring in terms of the inferior epigastric vessels:
The deep inguinal ring is lateral to the inferior epigastric vessels
List the contents of the spermatic cord:
Arteries: Testicular, Cremasteric, Artery to Vas
Veins: Pampiniform venous plexus
Nerves: Autonomics + Genital branch of the Genitofemoral nerve to Cremaster
Lymphatics
Vas deferens
Processus vaginalis
List some causes of a scrotal swelling:
- Hydrocoele
- Haematocoele
- Varicocoele
- Spermatocoele
- Epididymitis
- Inguinal hernia
- Testicular torsion
- Testicular cancer
- Orchitis
What is a hydrocoele?
Serous fluid in tunica vaginalis, usually due to failure of processus vaginalis to close
What is a haematocoele?
Blood in tunica vaginalis
What is a varicocoele?
Gross dilation of veins draining testes. Usually affects left testicle, as left testicular vein drains vertically into left renal vein, and lacks valves.
What is a spermatocoele?
Benign cystic accumulation of sperm, usually from head of epididymis
What is epididymitis?
Inflammation of epididymis usually due to viral or bacterial infection
What is the difference between a direct and indirect inguinal hernia?
Direct = via Hesselbach's triangle = medial to inferior epigastric vessels Indirect = via deep inguinal ring = lateral to inferior epigastric vessels
How can you differentiate between a haematocoele, and a hydrocoele?
Transillumination
- Light is unable to pass through the dense blood of a haematocoele
What is the most common age for testicular torsion to occur?
13-17 yrs
Where does testicular cancer most commonly metastasise to?
Para-aortic lymph nodes
- from here may spread to cervical lymphatics = Virchow’s node
How can testicular cancer cause an enlarged left supraclavicular lymph node (Virchow’s node)?
Testicular lymphatics drain via the thoracic duct into the left subclavian vein
What is oligozoospermia?
Abnormally low spermatozoa count in semen
What is azoospermia?
No spermatozoa in semen
What is Cryptorchid, and why is associated with low sperm count?
Maldescended testes
Increased temperature is suboptimal for spermatogenesis
What is orchitis?
Inflammation of the testes, usually due to bacterial infection (STI), or the mumps virus
What is the course of the vas deferens?
- From tail of epididymis, ascends in spermatic cord through inguinal canal
- Curves lateral then medial, looping over epigastric artery on lateral pelvic wall
- Travels medial to distal ureter along posterior wall of bladder
- Forms dilated ampulla and opens into ejaculatory duct
The seminal vesicles are a diverticulum of what structure?
Dilated ampulla of vas deferens
What is a vasectomy?
Both vas deferens are sectioned and ligated, from the superoanterior scrotal wall.