Part 14: Male Internal Genital Organs Flashcards
Where does the prostate lie? What is it’s shape and size?
Between bladder and urogenital diaphragm. Shape of chestnut, 4x3x2cm
How much seminal fluid is made by prostate and seminal vesicles?
Prostate: 30%
Seminal vesicles: 60%
Where is the base and apex of prostate?
Base: upper surface, adjacent to bladder
Apex: Blunt, lowest part, prostatic urethra becomes membranous urethra upon emergence
What is the structure of the prostate?
Consists of acini of varying shapes/sizes embedded in fibromuscular stroma (mixture of connective tissue and smooth muscle). Numerous small ducts open into prostatic urethra
Describe the capsule of the prostate
Inner true capsule - thin layer of connective tissue
Outer false capsule - condensation of pelvic fascia
Venous plexus between layers
How many lobes to prostate, which one cause obstruction of urethra?
5 - anterior, middle, posterior and lateral lobes (although no clear distinction)
Middle lobe hypertrophies in benign enlargement and compresses urethra
Describe the prostatic urethra
From internal urinary meatus to apex of prostate.
Midline longitudinal ridge (urethral crest).
Ejaculatory ducts open lateral to ridge, prostatic ducts open on crest and in sulcus on each side
What is the prostatic utricle?
Small opening on urethral crest which is embryological remnant - homologue of uterus
Describe the course of the ductus deferens
Continuation of epididymis - enters abdo at DIR, hooks around inferior epigastric A. Crosses EIA, obliterated umbilical art, obturator N/A/V, curves medially crosses ureter and approaches opposite fellow towards midline. Dilate into ampulla, medial to seminal vesicles. Structures join to form ejaculatory ducts which pass obliquely into prostate.
Is the ductus deferens crossed by any structures in pelvis?
No, no structures come between DD and peritoneum.
What is the blood supply of ductus deferens?
Superior vesical, anastomosing with testicular
What is the structure of ductus deferens?
Very thick walled due to muscle layer.
Pseudostratified epithelium with steriocilia
Describe the seminal vesicles
Thin walled, elongated sacs, folded on itself. lies lateral to DD, joins it to become ejaculatory duct
What is the nerve supply of DD and seminal vesicles?
Smooth muscle from pelvic plexus. Sympathetic fibres are motor and their disruption causes sterility due to lack of emission and ejaculation
