male external genital organs.pptx

male external genital organs

1. Male External Genital Organs Dr. Amaan 10 th August / Wednesday .

2. EXTERNAL GENITAL ORGANS 1. Penis, 2. Scrotum, 3. Testes, 4. Epididymes, and 5. Spermatic cords.

3. 1. Penis The penis is the male organ of copulation It provide passage for both urine & semen It is made up of: A root / radix or attached portion, Body / corpus or free portion

4. Root / radix , attached portion of penis Situated in the superficial perineal pouch. It is composed of three masses of erectile tissue, namely the two crura and one bulb. Crus is attached to the margins of the pubic arch , and is covered by the ischiocavernosus . The bulb is attached to the perineal membrane in between the two crura. It is covered by the bulbospongiosus .

5. Its deep surface is pierced by the urethra to reach the corpus spongiosum The part of the urethra within the bulb shows a dilation in its floor – intra bulbar navicular fossa .

6. (a) Male genital organs; parts of the penis—(b) ventral view, and (c) sagittal section

7. Transverse section through the body of the penis

8. Body / corpus of Penis Right and left corpora cavernosa Lies in front of scrotum continuation of the crus of the penis , do not reach the end of the penis At the inferior border of the pubic symphysis the two crura come together and continues as corpora cavernosa Surrounded by fibrous envelope: tunica albuginea (superficial longitudinal & deep circular fibres)

9. 2. Median corpus spongiosum forward continuation of the bulb of the penis. Its terminal part is expanded to form a conical enlargement, called the glans penis traversed by urethra

10. Body / corpus of Penis 3 parts: Body proper : in flaccid state it is long cylindrical structure, directed downwards & forwards Glans penis: terminal, expanded part of corpus spongiosum Neck of penis: oblique grooved constriction behind the base of glans

11. The penis has a: ventral surface : faces backwards and downwards, dorsal surface : faces forwards and upwards

12. . The base of glans has a projecting margin: corona glandis , which overhangs an obliquity grooved constriction: the neck of the penis Within the glans, the urethra shows a dilation: navicular fossa . The skin of the penis is very thin, dark . At neck it is folded: prepuce/ foreskin

13. On the undersurface of the glans, there is a median fold of skin: frenulum The potential space between the glans & the penis : preputial space on corona glandis & neck there are sebaceous glands, which secrete : smegma

14. Superficial fascia of penis: consists of very loosely arranged arolar tissue completely devoid of fat contains superficial vein of the penis Deep fascia of penis/ Buck’s fascia: it surrounds all the three masses of erectile tissue does not extend into the glans deep to it are: Deep dorsal vein, Deep dorsal arteries, Dorsal nerves of the penis

15. supports of the body of penis The fundiform ligament : it extends downwards from linea alba & splits to enclose penis It lies superficial to the suspensory ligament The suspensory ligament: extends from the pubic symphysis and blends below with the Buck’s fascia on each side of the penis

16. Arteries of the Penis The internal pudental artery gives 3 branches: The deep artery of the penis The dorsal artery of the penis The artery of the bulb of the penis The femoral artery gives:- superficial external pudental artery Veins of the penis superficial dorsal vein of the penis Deep dorsal vein of the penis

17. Transverse section through the body of the penis

18. Nerve Supply of the Penis The sensory nerve supply derived from: the dorsal nerve of the penis and the ilioinguinal nerve The autonomic nerves are derived from the pelvic plexus via the prostatic plexus. The sympathetic nerves are vasoconstrictor , the parasympathetic nerves are vasodilator ( erection is controlled by nervi eregentes S2-S4)

19. Lymphatic Drainage Lymphatics from the glans drain into the deep inguinal nodes , also called gland of Cloquet . Lymphatics from the rest of the penis drain into the superficial inguinal lymph nodes .

20. Mechanism of Erection of the Penis Dilatation of the helicine arteries (deep artery of the penis) This enlargement presses the veins Expansion of the corpora cavernosa, Erection is controlled by parasympathetic nerves (nervi erigentes, S2–S4).

21. Clinical correlation Impotence : failure to achieve tumescence erection psychogenic disturbance with failure to relax the smooth muscle Arterial insufficiency Involvement of nervi eregentes (S2-S4) 2. Pripism : persistant erection, due to persistent spasm of venous smooth muscles 3. Peyronie’s disease: Localized thickening or plaque of corpora cavernosa, which prevent expansion of erectile tissue; results in curved penis during erection

22. 3. Phimosis: narrowing of the distal end of the prepuce, which prevent retraction over the glans & may interfere with the micturition 4. Paraphimosis: uncommon condition, prepuce get stuck on the glans during erection & interfere with copulation 5. Circumscision : surgical removal of the foreskin, to relieve from tightly constrcting prepuce (phimosis)

23. 2. SCROTUM The scrotum (Latin bag) is a cutaneous bag containing the right and left testes , the Epididymes and the lower parts of the spermatic cords.

24. Layers of the Scrotum 1. Skin 2. Dartos muscle 3. The external spermatic fascia from external oblique muscle. 4. The cremasteric muscle and fascia from internal oblique muscle. 5. The internal spermatic fascia from fascia transversalis

25. Blood Supply Superficial external pudental Deep external pudental Scrotal branches of external pudental Cremasteric branch of inferior epigastric Nerve Supply The anterior one-third: by segment L1 through ilioinguinal nerve & genitofemoral nerve The posterior two-thirds: segment S3 .

26. some common abnormalities of scrotal contents are:- Tumors of the testis Hydrocoele (accumulation of fluid) Epididymitis (inflammation of epididymis) Variocoele (enlargement of the veins within the scrotum) Spermatocoele (spermatic cysts) Scrotal edema

27. 3. Testis The testis is the male gonad. It is homologous with the ovary of the female It is suspended in the scrotum by spermatic cord External Features 1. Two poles or ends: upper & lower 2. Two borders, anterior and posterior 3. Two surfaces, medial and lateral

28. Coverings of the Testis • The tunica vaginalis : parietal & visceral layer • The tunica albuginea • The tunica vasculosa

29. (a) Testis epididymis, sinus of the epididymis, and (b) longitudinal section of testis and epididymis

30. Structure of the Testis The glandular part of the testis consists of 200 to 300 lobules. Each lobule contains 2-3 seminiferous tubules . The seminiferous tubules join together at the apices of the lobules to form 20 to 30 straight tubules . Here they form a network of tubules, the rete testis . In its turn, the rete testis gives rise to 12 to 30 efferent ductules which emerge near the upper pole of the testis and enter the epididymis .

31. Arterial Supply The testicular artery from abdominal aorta Venous Drainage The veins emerging from the testis form the pampiniform plexus Right vein drains into inferior vena cava . Left vein drains into left renal vein . Lymphatic Drainage The lymphatics from the testis ascend along the testicular vessels and drain into the preaortic and para-aortic groups of lymph nodes.

32. Nerve Supply Sympathetic nerves arising from segment T10 of the spinal cord. Clinical Unilateral absence of testis: monorchism bilateral absence of testis: anorchism Undescended testis: cryptoorchidism Ectopic testis: the testis may occupy an abnormal position due to deviation

33. 4. Epididymis The epididymis is an organ made up of highly coiled tube that act as reservoir of spermatozoa. Parts Head: connected to upper pole of the testis by efferent ductules body Tail: single highly coiled duct which continuous as ductus deferens/ vas deferens

34. 6. Spermatic Cord The ductus deferens. The testicular and cremasteric arteries , and the artery of the ductus deferens. The pampiniform plexus of veins . Lymph vessels from the testis The genital branch of the genitofemoral nerve , and the plexus of sympathetic nerves around the artery to the ductus deferens and visceral afferent nerve fibres. Remains of the processus vaginalis.

35. Transverse section through the spermatic cord

36. Descent of the Testis • The testes develop in the upper abdomen, migrates out of the abdominal cavity into the scrotum. It reaches the iliac fossa by the 3rd month, • Rests at the deep inguinal ring (4-6 month) • Traverses the inguinal canal (7 th month) • Reaches the superficial inguinal ring (8 th month) • And the bottom of the scrotum by the 9th month or just after birth.

37. Stages of descent of testis include formation of processus vaginalis

38. Thank you