Anatomy and physiology of prostate

detailed anatomy and physiology of prostate

1. ANATOMY AND PHYSIOLOGY OF PROSTATE DR.LEELA KRISHNA

2. EMBROYOLOGY

3. SUBDIVISIONS OF THE CLOACA

4. MESODERMAL AND ENDODERMAL DERIVATIVES OF PROSTATE

5. PROSTATE Pyramidal fibromuscular gland Weight 20 gms About 3x4 x 2 cm Location; Extend from neck of bladder to urogenital diaphragm Has base and apex Pierced by urethra, ejaculatory ducts and prostatic utricle

6. RELATIONS Anteriorly Posteriorly Superiorly Inferiorly Laterally

7. Conical shape with base (sup), apex ( inf ), four surfaces Surfaces: posterior, anterior, right & left inferolateral Base ( superior) - Attached to neck of urinary bladder - Prostatic urethra enters middle of base close to anterior surface

8. Apex( inferior ) - Rests on superior fascia of urogenital diaphragm muscle - Associated with sphincter urethrae - Contacts medial margins of levator ani muscles Posteriorly - triangular, flat -separates from rectum by fascia of denonvilliers

9. Anterior - narrow & convex - separtes from pubic symphysis by retro pubicspace - RETZIUS SPACE - connected to pubic bones by prostatic ligaments Inferolaterally - anterior fibers of levator ani

10. CAPSULES True capsule -condensation of peripheral part of gland - contains no venous plexus False capsule - derived from pelvic fascia - anteriorly continues as puboprostatic ligament prostatic venous plexus embedded - posteriorly formed by rectovesical fascia of denonvillers

11. MC NEAL ZONAL ANATOMY

12. TRANSITIONAL CENTRAL PERIPHERAL 5% of glandular tissue 25% 70% Ducts arise and pass beneath pre prostatic sphincter Ducts arise circumferentially around opening of ejaculatory ducts Ducts drain into prostatic sinus in post sphincteric urethra Commonly give rise To BPH Commonly give rise to carcinoma and chronic prostatitis Sampled in most random biopsy of prostrates

13. TRUS

14. MRI

15. ULTRASOUND

16. HYPERPLASTIC PROSTATIC LOBES

17. PROSTATIC URETHRA Runs along length of prostate , closest to anterior surface lined by transtional epithelium At midpoint, urethra turns 35* anteriorly divides prostatic urethra into preprostatic urethra prostatic urethra

18. Urethra --Posterior part Preprostatic urethra is approximately 1 cm in length, and extends from the base of the bladder to the prostate. Small periurethral glands at this site may contribute to benign prostatic hyperplasia (BPH) and symptoms of outflow obstruction in older men.

19. Prostatic urethra closer to the anterior than the posterior surface of the gland. 3–4 cm in length , tunnels through the substance of the prostate continuous above with the preprostatic part and emerges from the prostate slightly anterior to its apex

20. the posterior wall possesses a midline ridge , THE URETHRAL CREST which projects into the lumen causing it to appear crescentic in transverse section. On each side of the crest there is a shallow depression, the prostatic sinus, the floor of which is perforated by the orifices of 15–20 prostatic ducts.

21. An elevation, the verumontanum (seminal colliculus ), is seen at about the middle of the length of the urethral crest NOTE : it is used as a surgical landmark for the urethral sphincter during trans-urethral resection for benign enlargement of the prostate .

22. VERUMONTARUM

23. On both sides of, or just within, this orifice are the two small openings of the ejaculatory ducts. The lowermost part of the prostatic urethra is fixed by the puboprostatic ligaments and is therefore immobile

24. TURP

25. TURP

26. TRANSURETHRAL INCISION

27. ARTERIAL SUPPLY Arteries derived from: Internal pudendal artery Inferior vesical artery Middle rectal artery

28. CONTD…..

29. Inferior vesical artery Divides into two branch - Urethral artery - Capsular artery -Approaches at bladder Runs posterolaterally neck at 1 to 5 O ’ clock along with and 7 to 11 O’clock neurovascular -On resection of gland bundle -These vessels bleed significantly specially those at 4 and 8 O’clock position

30. VENOUS DRAINAGE The veins of the prostate drain into Santorini's plexus deep dorsal vein leaves penis under Buck's fascia between corpora cavernosa and penetrates urogenital diaphragm, dividing into three major branches : superficial branch and the right and left lateral venous plexuses

31. superficial branch, which travels between the puboprostatic ligaments , is the centrally located vein overlying the bladder neck and prostate The superficial branch lies outside the anterior prostatic fascia.

32. The common trunk and lateral venous plexuses - covered and concealed by the prostatic and endopelvic fascia . lateral venous plexuses traverse posterolaterally and communicate freely with pudendal , obturator , & vesical plexuses ..

33. lateral plexus interconnects with other venous systems to form inferior vesical vein, empties into the internal iliac vein Laceration of these friable structures can lead to considerable blood loss

34. NERVE SUPPLY Pelvic Plexus The autonomic innervation of the pelvic organs arises from the pelvic plexus , which is formed by parasympathetic fibers that arise from the sacral center (S2 to S4 ) and sympathetic fibers via the hypogastric nerve from the thoracolumbar center.

35. The branches to the membranous urethra and corpora cavernosa travel outside the prostatic capsule in the lateral pelvic fascia dorsolaterally between prostate and rectum Although these nerves are microscopic, their anatomic location can be estimated intraoperatively by use of the capsular vessels as a landmark. Neurovascular bundle of Walsh

36. cavernous branches join the capsular arteries and veins to form the neurovascular bundle 20 to 30 mm distal to the junction of the bladder and prostate The neurovascular bundles are located in the lateral pelvic fascia between the prostatic fascia and the levator fascia .

37. LYMPHATIC DRAINAGE Primarily into obturator and internal iliac lymph nodes Small portion into presacral and external iliac nodes

38. PROSTATE CELL TYPES

39. CONTD….

40. STROMAL EPITHELIAL INTERACTIONS

41. PLASMA TRANSPORT AND METABOLISM OF TESTOSTERONE

42. ANDROGEN ACTION

43. ANDROGEN RECEPTORS Intracellular steroid binding protein ,activated by androgens activated by androgens resulting in both genomic and nongenomic actions Regulation is central to development and homeostasis in both stromal and epithelial elements GATEKEEPERS

44. ESTROGEN RECEPTORS

45. REGULATION OF PROSTATE

46. ENDOCRINOLOGY OF PROSTATE

47. THERAPEUTIC APPROACHES TO ANDROGEN DEPRIVATION THERAPY

48. PROSTATIC SECRETIONS AND PROTEINS Average volume is 3 ml ( 2 to 6 ml ) Major from s eminal vesicles ( 1.5 -2 ml) prostate ( 0.5 ml), Cowper gland and gland of littre ( 0.1 -0.2 ml)

49. CONTD… Citric acid Fructose Polyamines Phosphorylcholine Prostaglandins zinc

50. PROSTATIC SECRETORY PROTEINS Prostate specific antigen Human kallikrein 2,L1,11,14 Prostate specific transglutaminases Semenogelins 1 and 2 Prostate specific membrane antigen Prostate stem cell antigen Prostate acid phosphatase

51. CONTD… Protein c inhibitor Leucine aminopeptidase Lactate dehydrogenase Immunoglobulins,c3 complementand transferrin Zinc alpha 2 glycoprotein Seminal vesicle secretory proteins

52. CONTD …... Proteases – significant and dose dependent on semen liquefaction PSA – secreted in high concentrations in ejaculate ,regulation of semen coogulation PCI – abundant in seminal fluid ,responsible mainly interaction among semenogelins resulting in protein – protein interactions crucial to semen coogulation and liquefaction