Male Reproductive System 1 Flashcards
What are the main features of the scrotum?
- rugose skin
- contains dartos muscle (smooth)
- has midline raphe and divided by septum
What nerves supply the dartos muscle?
sympathetic fibres in genital branches of genitofemoral nerves
Describe how the anterolateral abdominal wall contributes to the scrotum in development
- during development testes migrate from posterior abdo wall through anterior wall into scrotum
- takes the layers of the abdominal walls, ductus deferens, testicular vessels and loop of parietal peritoneum known as processus vaginalis with it
- becomes tunica vaginalis after birth and lies as a closed potential space
- forms layers of scrotum
What is the clinical significance of the proximal part of the tunica vaginalis staying patent?
- indirect inguinal hernia
- hydrocele (fluid accumualtion)
What are the layers of the scrotum from superficial to deep?
- skin
- subcutaneous tissue (dartos muscle and fascia)
- external spermatic fascia
- cremasteric muscle and fascia (from internal oblique)
- internal spermatic fascia (from transversalis)
- tunica vaginalis (visceral and parietal layers from peritoneum)
What is the blood supply/drainage of the scrotum?
Arteries:
- anterior (1/3): external pudendal branches of femoral artery
- posterior (2/3): braches of internal pudendal branch of internal iliac artery
Veins:
- anterior (1/3): external pudendal veins to great saphenous vein
- posterior (2/3): internal pudendal vein to internal iliac vein
What is the nerve supply and lymphatic draingage of the scrotum?
Nerves:
- anterior (1/3): L1 with ilioinguinal and genitofemoral nerves
- posterior (2/3): S2-3 by scrotal branches of the perineal branches of pudendal nerve
Lymphatics:
- superficial inguinal nodes
Where would you aspirate for hydrocele?
- between the layers of tunica vaginalis
- aspirated by anterior or lateral approach to avoid posterior epididymis
What are the important features of the testes?
- in scrotum
- suspended by the spermatic cord
- tethered by gubernaculum
- left testes is lower than the right
- produces sperm and secretes testosterone (Leydig) and inhibin (Sertoli)
Describe the tunica albuginea
- it is a tough, fibrous collagenous layer around the testes
- maintains internal pressure
- sends in septae to create seminiferous lobules where the seminiferous tubules are
(location of spermatogenesis)
What is the function of the epididymis?
- maturation and acquisition of motility of spermatozoa
- during ejaculation, contractions of smooth muscle on the wall of epididymis expel the mature spermatozoa into the ductus deferens
What are the different parts of the epididymis?
- head
- body (descending)
- tail
- vas deferens (curves back on itself and ascends up)
What is the blood supply/drainage of the testes?
Arteries:
- testicular artery from aorta at L2
- anastomosis with cremasteric artery and artery to ductus deferens
Veins:
- testicular vein
What is the lymphatic drainage and nerve supply of the testes?
Lymphatics:
- lymph to para-aortic (lumbar) nodes
Nerve Supply:
- sympathetic lesser splanchnic nerve T10-11
(referred pain is periumbilical)
Describe the position of the vas deferens
- lies posterior to testis and medial to epididymis
- leaves scrotum and passes through abdominal wall within spermatic cord in the inguinal canal
- emerges into abdomen lateral to inferior epigastric artery and lies on lateral wall of pelvis
- passes anteromedially to ureter
What is found in the spermatic cord?
Blood Vessels:
- testicular vessels (artery (from aorta L2) and pampiniform venous plexus)
- artery of ductus deferens (from superior vesical artery)
- cremasteric artery and vein (from inferior epigastric artery)
Tubule Structures:
- ductus deferens (carrying sperm from epididymis to ejaculatory duct)
- lymphatic vessels (from testes to para-aortic nodes)
- vestige (of processus vaginalis)
Neural Structures:
- genital branch of genitofemoral nerve (cremaster muscle)
- sympathetic afferents and efferents (from lesser splanchnic nerve T10-11)
Describe the cremasteric reflex?
- tests L1
- ipsilateral testicular retraction when stroking superior medial thigh
Describe varicocele
- dilated and tortuous pampiniform plexus in scrotum
- almost always left sided
- dull aching, throbbing pain
- can cause infertility
Describe the locations and functions of the ejaculatory duct and seminal vesicle
Ejaculatory duct:
- from union of vas deferens and duct of seminal vesicle
- releases contents into prostatic urethra
Seminal vesicle:
- left and right seminal glands lie above prostate glands between bladder and rectum
- secrete seminal fluid to nourish sperm
Describe the location of the prostate
- inferior to neck of bladder
- posterior to pubic symphysis
- anterior to rectum
- superior to urogenital diaphragm
What is the function of the prostate?
- secretes at time of ejaculation:
- prostaglandins
- acid phosphatase
- proteolytic enzymes
- protease-specific antigen
Where do the prostatic and ejaculatory ducts open?
- prostatic ducts open into the prostatic sinuses that lie on either side of the seminal colliculus on posterior wall of prostatic urethra
- prostatic utricle opens onto centre of seminal colliculus
- on each side of prostatic utricle is opening for ejaculatory ducts
What are the lobes of the prostate and what areas are susceptible to tumours?
- 5 lobes
- median lobe: between urethra and ejaculatory ducts (benign prostatic hypertrophy)
- posterior lobe: behind urethra, inferior to ejaculatory ducts
- anterior lobe: anterior to urethra, no glandular tissue
- left and right: on either side of urethra
What are the MacNeal’s Zones and what areas are susceptible to tumours?
- transitional zone: around urethra and anterior to ejaculatory ducts (benign prostatic hypertrophy)
- central zone: posterior to transitional, contains ejaculatory ducts
- peripheral zone: around transitional and central (carcinomas)
- anterior zone
What is the arterial supply and venous drainage of the prostate?
- inferior vesical artery
- prostatic venous plexus (drains to internal iliac vein and has connections with vertebral vein)
