Male Reproductive System Lecture PDF

Anatomy – MED 201 Dr. Adamantios Michalinos M.D, M.Sc, Ph.D Anatomy Lecturer  Male reproductive Overview Functions  Reproduction  Sexual intercourse  Urination Parts  Internal Genitalia  External genitalia ...

Anatomy – MED 201 Dr. Adamantios Michalinos M.D, M.Sc, Ph.D Anatomy Lecturer  Male reproductive Overview Functions  Reproduction  Sexual intercourse  Urination Parts  Internal Genitalia  External genitalia  Learning objectives  Discover the basis of the male genitals development  Describe the anatomy of the male external genital organs  Explore the anatomy of the male urethra  Visualize the male internal genital organs’ anatomy  Organs of male reproductive system  Testis Sperm production  Epididymis  Seminal vesicle  Ductus deferens Sperm maturation &  Spermatic cord conduction  Ejaculatory duct  Prostate  Male urethra  Bulbourethral glands  Male urethra  Scrotums Sexual intercourse  Penis  Embryology Gonads => testes differentiation (Y chr/TDF) – Leydig cells – Sertoli cells _ + Mesonephros – Mullerian (paramesonephric) ducts – Wolffian (mesonephric) ducts Testosterone – Epididymis DHT – Vas deferens – Seminal vesicles Penis Prostate  Embryology  Descent of the testes (28th week)  Gubernaculum Retroperitoneal fibrous tract Connecting testis with primordial scrotum  Processus vaginalis Peritoneal diverticulum Traverses the inguinal canal Ectopic testis  Ectopic testis Parts  Root  Body  Glans Anatomical position?  Penis  Root Crura & bulb of penis Ischiocavernous & bulbospongious muscles  Penis Suspensory & fundiform ligament of penis  Penis Body 3 cylindrical cavernous bodies Corpora cavernosa (x2) Corpus spongiosum (contains urethra) Tunica albuginea (covering each cavernous body) Deep fascia of the penis (Buck’s fascia)  Penis  Arteries: dorsal (x2), deep (x2)  Veins: deep dorsal, superficial dorsal veins  Nerves: dorsal nerve of penis (pudental n, S2-S4)  Penis  Root  Body  Glans Corona of the glans Neck of the glans External urethral orifice Prepuce (foreskin) Frenulum of prepuce Mechanism of erection  Male urethra  18-22 cm length from internal to external urethral orifice  Intramural (preprostatic) urethra  Prostatic urethra  Intermediate (membranous) urethra  Spongy (cavernous) urethra  Male urethra Intramural (preprostatic) urethra – Internal urethral sphincter (smooth muscle) Prostatic urethra – Prostatic sinuses – Ejaculatory ducts Intermediate (membranous) urethra Spongy (cavernous) urethra  Male urethra  Intramural (preprostatic) urethra  Prostatic urethra  Intermediate (membranous) urethra  Surrounded by external urethral sphincter  Penetrates perineal membrane  Spongy (cavernous) urethra  5mm diameter  Intrabulbar fossa  Navicular fossa  Ducts of bulbo-urethral glands  Scrotum  Cutaneous sac containing the testes  Pigmented skin  Dartos fascia  Dartos muscle => testis suspension, scrotum skin wrinkling  Septum of the scrotum (right and left compartment)  Continuation of Scarpa’s fascia and Colle’s fascia  Scrotum Skin Dartos muscle/fascia External spermatic fascia Cremaster muscle/fascia Internal spermatic fascia Tunica vaginalis – External layer – Internal layer  Testes Male gonads – Production of sperm – Secretion of testosterone Tunica vaginalis (closed peritoneal sac) – Closed distal part of processus vaginalis – Parietal layer – Visceral layer => partially surrounds testis Tunica albuginea – Tough fibrous layer – Testis mediastinum – Fibrous septa  Testes Testis parenchyma Seminiferous tubules – Form lobules between the septa Straight tubules Rete tests Efferent ductules  Testes spermatic veins  Testes vascularization  Right & left testicular artery: From abdominal aorta  Testicular veins  Right  Directly to Inferior Vena Cava  Left  Renal vein Testicular torsion  Epididymis  Elongated structure of the posterior surface of testis  Duct of epididymis (tight convolutions)  Head  Body  Tail => ductus deferens  Ductus deferens  Thick walled, cord-like structure  Course  Continuation of epididymis duct  Component of the spermatic cord  Crosses external iliac vessels  Lateral pelvis wall  Joins the duct of seminal gland to form the ejaculatory duct  Contained inside the spermatic cord  Spermatic cord Collective name for structures associated with the scrotum  Vas deferens (ductus deferens)  Testicular a. & v.  Lymphatic  Nerves  Ilioingunal  Genital branch of genitofermoral  Spermatic vesicle Seminal glands (vesicles)  5 cm length  Between fundus of bladder and rectum  Superior part covered with peritoneum of rectovesical pouch  Secretion of thick alkaline fructose rich fluid & coagulating agent  Ejaculatory ducts Ejaculatory ducts  2.5 cm length  Union of the seminal glands ducts and the ductus deferens  End near the prostatic utricle  The prostate  Walnut sized accessory gland  Glandular/fibromuscular part  5 Lobes  Isthmus (anterior)  Median  Posterior  Lateral right/left lobes  Fibrous capsule of the prostate  Prostatic venous plexus  Prostatic sheath (visceral layer of pelvic fascia)  The prostate Prostatic urethra Urethral crest – Posterior wall of prostatic urethra – Seminal colliculus Prostatic utricle Openings of ejaculatory ducts Prostatic ducts (x20-30) – Prostatic sinuses – Prostatic fluid (thin, milky fluid)T  Bulbo – urethreal lands Bulbo-urethral glands (Cowper glands) Pea sized Embedded within the external urethral sphincter Opening in the proximal spongy urethra Mucus-like secretion  Innervation Internal genital organs Testes Sympathetic S: T10 T12-L2 P: vagus n. Lumbar splanchnic Testicular nerves plexus Parasympathetic Penis S2-S3 S2-S4 Pelvic splanchnic Pudendal n nerves Ilio-inguinal n Hypogastric pelvic plexuses Questions?