Flashcards in Week 4.0 - Male Reproductive tract Deck (45):
What is the scrotum?
-A cutaneous sac developed from labioscrotal folds which contains the testis, epididymis and spermatic cord (first part)
Describe the layers of the testis
-Internal spermatic fascia
-Cremastic muscle and fascia
-External spermatic fascia
How are the testis organised?
-Lobules of seminiferous tubules divided by fibrous septae
Describe the descent of the testis
-Gonads develop on urogenital ridge on posterior abdominal wall
-Descend behind the peritoneum through the abdomen
-Take an oblique passageway across anterior abdominal wall, following processes vaginalis, forming inguinal canal
Describe the arterial supply and venous drainage of the testis
-Arterial supply is directly from abdominal aorta
-Venous drainage R testicular vein to IVC, L testicular vein to L renal vein then L IVC
What connects the lobules of seminiferous tubules and the epididymis?
-Rete testis and efferent ductules
What does the spermatic cord contain?
-Testicular A, cremasteric A, artery to vas deferens,
-Genital nerve (from genitofemoral nerve)
Where is the spermatic cord?
-From the deep inguinal ring to posterior border of testis via inguinal canal and superficial inguinal ring
What is the pampiniform plexus?
-Sophisticated venous drainage of the testis
-> acts as a heat exchanger as arterial blood passes into testis at core body temp but spermatogenesis is optimal at a few degrees lower -> venous drainage wraps arouns artery to allow heat to dissipate
Where is the internal spermatic fascia derived from?
Where is the cremasteric muscle and fascia derived from?
-Internal oblique and transversalis fascia
Where is the external spermatic fascia derived from?
-Aponeurosis of external oblique
-Swelling in the scrotum caused by serous fluid in tunica vaginalis
-Swelling in the scrotum causes by blood in tunica vaginalis
-Varicosities of pampiniform plexus
What is epididymitis?
-Inflammation of the epididymis often caused by STI
How do you determine between hydrocoele and haematocoele?
-White light = hydrocoele
-Pink light = haematocoele
What is an inguinal hernia?
-Outpocketing of bowel which has pushed through the anterior abdominal wall
-Direct through hesselbachs triangle
-Indirect through deep inguinal ring -> inguinal canal
What is the predisposing developmental factor to an indirect hernia?
-Reopening of processus vaginalis allowing communication between peritoneal cavity and scrotum
What is testicular torsion?
-Twisting of the testicles usually above the upper pole -> risk of necrosis
Describe the innervation to the testis
-Anterior = lumbar plexus
-Posterior/inferior = sacral plexus
Describe the lymphatic drainage of the testis and scrotum
-Testis drains to paraaortic nodes
-Scrotum drains to superficial inguinal nodes
Describe the course of the ductus deferens
-Ascends from the testes in spermatic cord
-Traverses inguinal canal
-Tracks around pelvic side wall
-Passes between ureter and bladder
-Forms dilated ampulla
-Opens into ejaculatory duct
What are the seminal vesicles?
-Outpuching of ductus deferens forming a glandular structure which secretes important ejaculate components
What forms the ejaculatory ducts?
-seminal vesicles combining with ductus deferens on both sides form one duct within prostate
What is the prostate?
-A fibromuscular gland which secretes components of ejaculate
Describe the anatomical relationships at the base of the prostate
-combines with neck of bladder
Describe the anatomical relationships at the apex of the prostate
-Attaches to urethral sphincter and perineal muscles
Describe the anatomical relationships at the anterior of the prostate
-Attaches to urethral sphincter
Describe the anatomical relationships at the posterior of the prostate
-Attaches to ampulla of rectum
Describe the structural organisation of the prostate
-Organised into central, transitional and peripheral zones
Describe the origins of the zones of the prostate
-Central zone from wolffian ducts
-Peripheral zone from UGS
Describe Benign Prostate Hyperplasia and its symptoms
-Proliferation of the central zone of prostate, often causing obstruction of the internal urethral orifice
-Dysuria, nocturia and urgency
Which part of the prostate do malignancies often affect? Why is this clinially significant?
-Present later as has to get very large before it affects micturition
How does prostatic malignancy often spread?
-Lymphatics via internal iliac and sacral nodes
-Venous routes via internal vertebral plexus to vertebrae and brain
What two characteristics are assessed during DRE?
-Size and consistency of prostate
Describe the internal structure of the penis
-Pair of corpora cavernosa dorsally
-Single corpus spongiosum ventrally
Through which part of the penis does the urethra pass?
Which arteries supply the penis and perineum?
-Branches of internal pudendal (which is branch of anterior internal iliac)
Which muscles are the main contributors to the male perineum?
What is the function of bulbospongiosus in males?
-Wraps around root of penis to help expel last drops of urine and maintain erection
What is the function of ischiocavernosus in males?
-Compress the veins and therefore help maintain the erection
Which is the least distensible part of the male urethra? Why? Why is this clinically significant?
-Confined by peritoneum and perineal floor
-Likely to meet resistance here during passage of catheter