Session 4 - Male reproductive anatomy Flashcards
What does the scrotum develop from?
The labioscrotal folds
What three main structures are contained within the scrotum?
Testis
Epididymis
Spermatic cord
What are the 6 main levels of the scrotum
1) Skin
2) Dartos muscle
3) External and internal spermatic fascia
4) Visceral and parietal tunica vaginalis
5) Tunic albuginea
6) Lobules of testes
What are the two main products of the testes?
Spermatozoa
Testosterone
What is the structure of the lobules of the testes?
Tubules in which sperm are produced. Connect to rete testis, where sperm is concentrated
Give the two main types of seminferous cells and their function
Sertoli Cells o Associated with Seminiferous Tubules o Spermatozoa development Leydig (Interstitial) Cells o Cells in the interstitial tissue o Secrete testosterone
Where do the testes arise embryologically?
Mesonephric ridge in the upper lumbar regions, at the lower pole of the kidney
What are the testes tethered to and how before they descend?
Labioscrotal folds by the gubernaculum
What is the processus vagnialis?
A musculo-fascial layer which invaginates into the scrotum to form the processus vaginalis
What is the scrotal ligament a remenant of?
The gubernaculum
What is the arterial supply of the testes?
Testicular arteries
What is the main form of venous drainage of the testes
Pampiform venous plexus -> Left and right testicular vein
Why does the pampiniform venous plexus have such a strange structure?
Large surfce area to help cool blood of testicular arteries - thermoregulatory function
What does the right testicular vein drain into?
The IVC
What does the left testicular vein drain into?
The left renal vein
What is varicoele, and how are they formed?
Defective valves in the testicular veins can cause blood palpable masses to form within the pampiniform venous plexus. This can cause fertility problems as a result of raised testicular temperature.
What are the three parts of the epididymis?
Head
Body
Tail
What are the three main functions of the epididymis?
Sperm transport
Maturation
Storage
What part of the epididymis are the sperm stored?
Tail segment
What is the innervation of the testes and scrotum?
o Lumbar Plexus
Anterior surface
o Sacral Plexus
Posterior and inferior surfaces
What is the lymphatic drainage of the testes?
Paraaortic nodes, which can only be seen by imaging
What is the lymphatic drainage of the scrotum?
Superficial inguinal nodes.
What is the function of the vas deferens?
Transports sperm rapidly to the prostatic urethra via smooth muscle fibre contraction
What happens to the ejaculatory duct and the duct of the seminal vesicle during ejaculation?
Dilate to facilitate the entry of spermatazoa
What is the path of the ductus (vas) deferens?
The ductus deferens ascends in the spermatic cord, traverses the inguinal canal, tracks around the pelvic side wall, passes between the bladder and ureter before forming a dilated ampulla and opening into the ejaculatory duct.
What is contained within the spermatic cord?
o Neurovascular
Testicular Artery, Cremasteric Artery, Artery to Vas
Pampiniform Plexus – Configuration of the testicular vein within spermatic cord, helix shape to increase surface area and take heat away from testicular artery.
Genital branch of Genitofemoral Nerve
o Vas Deferens
o Lymphatics
What are the three layers of the spermatic cord?
o External spermatic fascia – Aponeurosis of external oblique
o Cremasteric muscle and fascia – Internal oblique and transversalis
o Internal spermatic fascia – Transversalis fascia
What are the seminal vesicles?
Small glands which join the ampulla of the vas deferens to form the ejaculatory duct
What volume of semen to seminal vesciles account for?
70%
What are the three main secretions of the prostate?
Prostaglandins
Proteolytic enzymes
Citric acid
What volume of ejaculate does the prostate provide
30%
What are the bulbourethral glands?
These glands are located within the urogenital diaphragm and contain tubular and alveolar-type glands. Just prior to ejaculation, these glands produce a clear water secretion that may lubricate the urethra.
What are the two main parts of the penis when taken in cross section
pair of Corpoa Cavernosa dorsally and a single Corpus Spongiosum ventrally.
What is the blood supply of the penis
Abdominal Aorta -> Common Iliac -> Internal Iliac -> Anterior Division of Internal Iliac -> Internal Pudendal Artery
What is the venous drainage of the penis?
Venous Plexus of the Penis -> Deep Dorsal Vein of the Penis -> Prostatic Venous Plexus -> Internal Iliac Vein -> Inferior Vena Cava (IVC
Outline 6 pathologies of the scrotum and testes
o Hydrocoele of testis – Serous fluid in tunica vaginalis
o Hyrdocoele of cord – Serous fluid in spermatic cord
o Haematocoele – Blood in tunica vaginalis
o Varicocoele – Varicosities of the Pampiniform plexus
o Spermatocoele – Retention cyst within the epididymis, aka epididymal cyst
o Epididymitis – Inflammation of the epididymal cyst
How can you tell the different between a hydrocele and haematocoele of the testis?
haematocoele of the testis?
Transillumination – Haematocoele will absorb, hydrocele will be semi-transparent.
What is a direct inguinal hernia?
Hernia directly into the inguinal area
Medial to the inferior epigastric vessels
What is an indirect inguinal hernia?
Hernia indirectly into the inguinal area, via the inguinal canal
Lateral to the inferior epigastric vessels
Reopening of the Processus vaginalis gives potential continuity between the peritoneal cavity and tunica vaginalis (abdomen scrotum).
What is testicular torsion?
Testicular Torsion is twisting of the spermatic cord, giving the risk of necrosis of the testis. The twisting usually occurs just above the upper pole of the testis.
What is BPH?
Benign Prostatic Hyperplasia (BPH) occurs mainly in the central zone of the prostate. Due to the zone’s close proximity to the urethra, BPH can cause dysuria, nocturia and urgency.
Where do prostatic malignancies develop?
Peripheral zone of prostate
How do malignant mestastases spread?
The malignancies metastasise via the lymphatic route (internal iliac and sacral nodes) and venous route (internal vertebral plexus to vertebrae and brain).
What is the difference between BPH and prostatic malignancy in DRE?
A tumorous prostate will feel craggy, whereas BPH will have a smooth, enlarged feel.
