Pelvic Viscera Anatomy PDF

The Pelvic Viscera & Peritoneal Reflection Male Female By Soressa A (PhD) 1 Peritoneal reflections By Soressa A (PhD) 2 Pelvic Viscera include the: urinary bladder and parts of the ureters most...

The Pelvic Viscera & Peritoneal Reflection Male Female By Soressa A (PhD) 1 Peritoneal reflections By Soressa A (PhD) 2 Pelvic Viscera include the: urinary bladder and parts of the ureters most of the reproductive organs the distal part of the alimentary tract (rectum). the sigmoid colon parts of the coils of the small intestine, are abdominal rather than pelvic viscera. By Soressa A (PhD) 3 1. Urinary Organs The pelvic urinary organs are: 1. Pelvic part of ureters 2. Urinary bladder 3. Proximal pat of the urethra By Soressa A (PhD) 4 1. Ureters – the ureters are muscular tubes – is about 25 - 30 cm long – connect the kidneys to the urinary bladder – Retroperitoneal structure – their superior halves are in the abdomen – their inferior halves lie in the pelvis – cross the bifurcation of the common iliac artery or the beginning of the external iliac artery – they pass over the pelvic brim, thus leaving the abdomen and entering the lesser pelvis By Soressa A (PhD) 5 Pelvic parts of ureter enter the pelvis by crossing the end of common iliac artery pass backwards and downwards along the lower border of internal iliac artery run on the lateral wall of the pelvis b/n the parietal pelvic peritoneum and the internal iliac arteries curve anteromedially at the level of the ischial spine 1.5 cm above it enter the urinary bladder at posterosuperior angle pass obliquely through the muscular wall of the bladder for about 2 cm in an inferomedial direction before it opens into the bladder entering the outer surface of the bladder ≈ 5 cm apart, but their internal openings into the lumen of the empty bladder are separated by 2.5 cm By Soressa A (PhD) 6 By Soressa A (PhD) 7 – this oblique passage through the bladder wall forms a one-way flap valve, – the internal pressure of the filling bladder causing the intramural passage to collapse. – contractions of the bladder musculature act as a sphincter preventing the reflux of urine into the ureters when the bladder contracts, increasing internal pressure during micturition – Urine is transported down the ureters by means of peristaltic contractions – a few drops being transported at intervals of 12 - 20 sec By Soressa A (PhD) 8 Relations: covered medially by peritoneum as it descends, it crosses: – the external iliac artery – external iliac vein – obturator nerve – obturator vessels In males: the only structure that passes between the ureter and the peritoneum is the ductus deferens Crossed by ductus deferens within the ureteric fold of peritoneum near the wall of the bladder lies posterolateral to the ductus deferens enters the posterosuperior angle of the bladder By Soressa A (PhD) 9 In females: – the ureter descends on the lateral wall of the pelvic minor – here it forms the posterior boundary of the ovarian fossa – passes medial to the origin of the uterine artery – continues to the level of the ischial spine, where it is crossed superiorly by the uterine artery – passes close to the lateral part of the fornix of the vagina – enters the posterosuperior angle of the bladder – The left ureter is more intimately related to the upper end of the vagina. Why? By Soressa A (PhD) 10 Constrictions of ureter  at the junction of renal pelvis and ureter  as it crosses the pelvic brim  as it crosses the common iliac artery  as it joins the urinary bladder  as it open into the urinary bladder By Soressa A (PhD) 11 Blood supply: Variable branches from : – the common iliac arteries – internal iliac, and ovarian arteries extend to and supply the pelvic parts of the erecters – anastomosing along the length of the ureter to form a continuous blood supply The most constant arteries supplying the terminal parts of the ureter in females are branches of the uterine arteries. The source of similar branches in males are the inferior vesical arteries By Soressa A (PhD) 12 Venous drainage Veins from the ureters accompany the arteries and have corresponding names. Lymph drainage: sequentially, from superior to inferior, into the lumbar (caval/aortic) and common iliac nodes (abdominal part) and the external and internal iliac nodes (pelvic part) Innervation of the ureters The nerves to the ureters derive from adjacent autonomic plexuses (renal, aortic, superior and inferior hypogastric). The ureters are superior to the pelvic pain line Afferent (pain) fibers from the ureters follow sympathetic fibers in a retrograde direction to reach the spinal ganglia and spinal cord segments of T11 to L1 or L2 Ureteric pain is usually referred to the ipsilateral lower quadrant of the abdomen, especially to the groin (inguinal region) By Soressa A (PhD) 13 By Soressa A (PhD) 14 By Soressa A (PhD) 15 2. Urinary Bladder – is the most anterior structure of the pelvic viscera – Location: immediately behind the pubic bones within the true pelvis – a hollow viscus with strong muscular walls – characterized by its distensibility – varies in size, shape, position, and relationships according to its content and the state of neighboring viscera when empty, the adult urinary bladder is located in the lesser pelvis, lying partially superior to and partially posterior to the pubic bones By Soressa A (PhD) 16  separated from pubis by the potential retropubic space (of Retzius) lies mostly inferior to the peritoneum resting on: – the pubic bones and pubic symphysis anteriorly – the pelvic floor posteriorly The bladder is relatively free within the extraperitonium, except for its neck The neck is held firmly by: – the lateral ligaments of bladder – the tendinous arch of the pelvic fascia especially its anterior components – the puboprostatic ligament in males and the pubovesical ligament in By Soressa A (PhD) 17 females External surface of urinary bladder – Shape: The empty bladder is pyramidal – Has 1. An apex 2. A base 3. Three surfaces ( a superior and two inferolateral surfaces) 4. A neck 1. The apex Located superiorly, points toward the superior edge of the pubic symphysis when the bladder is empty. is connected to the umbilicus by the median umbilical ligament (remains of urachus). By Soressa A (PhD) 18 2. The base (fudus) located posteriorly, opposing the apex Is somewhat convex posterior wall is shaped like an inverted triangle faces posteroinferiorly 3. The body is the major portion between the apex and the fundus The fundus and inferolateral surfaces meet inferiorly at the neck of the bladder. By Soressa A (PhD) 19 4. Surfaces – Three surfaces 1. Superior surface – slightly domed when the bladder is empty – balloons upward as the bladder fills. – the only surface covered by peritoneum 2. The two inferolateral surface – separated from the pubis by retro-pubic space filled with retropubic fat pad – convergeAttached to pubis by puboprostatic ligament (male) or pubovesical ligament (female) by the By Soressa A (PhD) 20 5. Neck of bladder: formed by the convergence of the fundus and the two inferolateral surfaces continuous with the urethra inferiorly. lies about 2.5 cm behind the lower part of the symphysis pubis surrounds the origin of the urethra is the most inferior part of the bladder is the most inferior part of the bladder is the most 'fixed' part. In male, it rests on: prostatic gland and continuous with prostatic part of urethra In female – it is directly continuous with the urethra – related posterior to the anterior wall of the vagina By Soressa A (PhD) 21 6. Three angles: 1. two supero-posterior angle (superolateral angle) 2. the inferior angle By Soressa A (PhD) 22 The Bladder Bed the shape of the bladder is largely determined by the structures that are closely related to it. the entire enveloped by loose connective tissue, vesicle fascia vesical venous plexus- located within vesical fascia formed by the structures that directly contact with bladder the bladder bed is formed by: – on each side by the pubic bones – the levator ani muscles – the obturator internus muscle – posteriorly by the rectum By Soressa A (PhD) 23 The Interior of the Bladder Mucosa of the bladder: when empty, the mucosa is thrown into fold (rugae) the rugae disappears and smooth when the bladder is distended The trigone: is a smooth area on the interior of the base is bounded by the internal ureteric orifices (2.5 cm apart in the empty bladder) and the internal urethral orifice. the internal ureteric orifices are joined by the interureteric ridge (or crest). these ridges may extend past the ureteric openings laterally as the ureteric folds. By Soressa A (PhD) 24  In adult males, particularly past middle age there is a slight elevation of the mucosa posterior to the internal urethral orifice. this is known as the uvula and is formed by the median prostatic lobe. an enlarged prostate gland, this uvula may obstruct the internal urethral orifice Special features: thin, elastic, smooth and the most sensitive By Soressa A (PhD) 25 Musculature of the urinary bladder The wall of the urinary bladder is made up of: three layers: 1. mucosal layer 2.Muscularis layer 3.Serosal/ adventitia By Soressa A (PhD) 26  Muscle of the bladder – Made up of specialized smooth muscle known as detrusor muscle – Play key role in storage and emptying urine – Its fibres are orientated in multiple directions, thus retaining structural integrity when stretched – The fibres of the detrusor muscle often become hypertrophic (presenting as prominent trabeculae) in order to compensate for increased workload of the bladder emptying By Soressa A (PhD) 27 Arterial supply Mainly from branches of the internal iliac arteries – The superior vesical arteries supply anterosuperior parts of the bladder – In males, inferior vesical arteries supply the fundus and neck of the bladder – In females, the vaginal arteries replace the inferior vesical arteries and send small branches to posteroinferior parts of the bladder The obturator and inferior gluteal arteries also supply small branches to the bladder. By Soressa A (PhD) 28 Venous drainage of the bladder The names of the veins correspond to the arteries and are tributaries of the internal iliac veins. In males: – the vesical venous plexus is continuous with the prostatic venous plexus – the combined plexus complex envelops: the fundus of the bladder and prostate the seminal glands the ductus deferenes the inferior ends of the ureters also receives blood from the deep dorsal vein of the penis, which drains into the prostatic venous plexus. By Soressa A (PhD) 29 The vesical venous plexus: is the part of the plexus complex that is most directly associated with the bladder itself mainly drains through the inferior vesical veins into the internal iliac veins may drain through the sacral veins into the internal vertebral venous plexuses In females: – the vesical venous plexus envelops the pelvic part of the urethra and the neck of the bladder – receives blood from the dorsal vein of the clitoris, and communicates with the vaginal or uterovaginal venous plexus By Soressa A (PhD) 30 Lymphatic drainage: – in both sexes, lymphatic vessels from the superolateral aspects pass to the external iliac lymph nodes from the fundus and neck pass to the internal iliac lymph nodes Some vessels from the neck of the bladder drain into the sacral or common iliac lymph nodes. By Soressa A (PhD) 31 Innervation of the bladder Sympathetic fibers (T11, 12 – L1, 2): conveyed from inferior thoracic and upper lumbar spinal cord levels to the vesical (pelvic) plexuses primarily through the hypogastric plexuses and nerves Parasympathetic fibers (S2 – 4) – are conveyed by the pelvic splanchnic nerves and the inferior hypogastric plexus are motor to the detrusor muscle and inhibitory to the internal urethral sphincter of the male bladder the bladder contracts reflexively, the internal urethral sphincter relaxes (in males), and urine flows into the urethra With toilet training, we learn to suppress this reflex when we do not wish to void. By Soressa A (PhD) 32 By Soressa A (PhD) 33 The sympathetic innervation: stimulates ejaculation simultaneously causes contraction of the internal urethral sphincter, to prevent reflux of semen into the bladder. A sympathetic response at moments other than ejaculation (e.g., self- consciousness when standing at the urinal in front of a waiting line) can cause the internal sphincter to contract, hampering the ability to urinate until parasympathetic inhibition of the sphincter occurs. Sensory fibers from the bladder: are visceral reflex afferents follow the course of the parasympathetic fibers, as do those transmitting pain sensations (such as results from overdistension) from the inferior part of the bladder. The superior surface (roof) of the bladder is covered with peritoneum and is therefore superior to the pelvic pain line thus pain fibers from the superior bladder follow the sympathetic fibers retrogradely to the inferior thoracic and upper lumbar spinal ganglia (T11 - L2 or L3) By Soressa A (PhD) 34 3. Male pelvic viscera By Soressa A (PhD) 35 1. Male urethra division: – is a muscular tube the urethra is divided into – about 18 - 22 cm long four parts – conveys urine from the 1. Preprostatic part internal urethral orifice 2. Prostatic part of the urinary and 3. Membranous part bladder to the external 4. Penile part urethral orifice - located at the tip of the glans penis in males – the urethra also provides an exit for semen (sperms and glandular secretions) – In the flaccid (non-erect) state, the urethra has a double curvature. By Soressa A (PhD) 36 1. Preprostatic part  is in the bladder neck  about 0.5 - 1.5 cm long  extends almost vertically through neck of bladder Surrounded by internal urethral sphincter  diameter and length vary, depending on whether bladder is filling or emptying By Soressa A (PhD) 37 2. Prostatic urethra: – about 3.0 - 4.0 cm long – descends through anterior prostate, forming a gentle, anteriorly concave curve – is bounded anteriorly by a vertical trough-like part (rhabdosphincter) of external urethral sphincter – widest and most dilatable part – has features of urethral crest with seminal colliculus (rounded elvation formed by the urethral crest) -flanked by prostatic sinuses into which prostatic ducts open – ejaculatory ducts open onto colliculus, hence urinary and reproductive tracts merge in this part By Soressa A (PhD) 38 By Soressa A (PhD) 39 3. Membranous part – is about 1.0 - 1.5 cm long – passes through deep perineal pouch – surrounded by circular fibers of external urethral sphincter – penetrates perineal membrane – Narrowest and least distensible part (except for external urethral orifice) – Is called membranous urethra because it lies between the two fascial membrane ( pelvic fascia and perineal membrane By Soressa A (PhD) 40 4. Spongy urethra About 15 cm long Courses through corpus spongiosum Initial widening occurs in bulb of penis As it enters the bulb, the urethra expands to form a dilatation called intrabulbar fossa Widens again distally as navicular fossa (in glans penis) The fossa navicularis narrows to form the external urethra orifice- the narrowest of the whole urethra The Longest and most mobile part Bulbourethral glands open into bulbous part Distally, urethral glands open into small urethral lacunae entering lumen of this part By Soressa A (PhD) 41 By Soressa A (PhD) 42 Blood supply Arterial supply The proximal two parts of the urethra are supplied by: – prostatic branches of the inferior vesical artery – middle rectal arteries Venous drainage The veins from the proximal two parts of the urethra: – drain into the prostatic venous plexus Lymphatic drainage The lymphatic vessels pass mainly to: – the internal iliac lymph nodes – a few vessels drain into the external iliac lymph nodes By Soressa A (PhD) 43 Innervation of the proximal male Urethra – The nerves are derived from: the prostatic plexus (mixed sympathetic, parasympathetic, and visceral afferent fibers) – The prostatic plexus is one of the pelvic plexuses inferior extension of the vesical plexus arising as organ-specific extensions of the inferior hypogastric plexus By Soressa A (PhD) 44 Female Urethra approximately 4 cm long and 6 mm in diameter passes anteroinferiorly from the internal urethral orifice of the urinary bladder Descends posterior and then inferior to the pubic symphysis, to the external urethral orifice Traverses the pelvic diaphragm ,deep and superficial perineal pouches and open into the vestibule anterior to the vagina The musculature surrounding the internal urethral orifice of the female bladder is not organized into an internal sphincter. the external urethral orifice is located in the vestibule, directly anterior to the vaginal orifice. By Soressa A (PhD) 45  The urethra lies anterior to the vagina (forming an elevation in the anterior vaginal wall) its axis is parallel to that of the vagina. Urethral glands are present, particularly in the superior part of the urethra One group of glands on each side the paraurethral glands are homologues to the prostate These glands have a common paraurethral duct, which opens (one on each side) near the external urethral orifice. By Soressa A (PhD) 46 Arterial supply: the internal pudendal and vaginal arteries Venous drainage: The veins follow the arteries and have similar names Lymphatic drainage: Most lymphatic vessels from the urethra pass to: – the sacral and internal iliac lymph nodes – a few vessels from the distal urethra drain into the inguinal lymph nodes. By Soressa A (PhD) 47 By Soressa A (PhD) 48 Innervation: The nerves to the urethra arise from: – the vesical (nerve) plexus – the pudendal nerve. – The pattern is similar to that in the male, given the absence of a prostatic plexus and an internal urethra sphincter. Visceral afferents from most of the urethra run in the pelvic splanchnic nerves, but the termination receives somatic afferents from the pudendal nerve Both the visceral and the somatic afferent fibers extend from cell bodies in the S2 - S4 spinal ganglia. By Soressa A (PhD) 49  Clinically significant differences between male and female urethra The female urethra: – is distensible because it contains considerable elastic tissue, as well as smooth muscle – can be easily dilated without injury – consequently, the passage of catheters or cystoscopes is easier in females than in males Infections of the urethra, and especially the bladder, are more common in women because the female urethra is: – short – more distensible – is open to the exterior through the vestibule of the vagina By Soressa A (PhD) 50 Male Internal genital organs include: the testes epididymides ductus deferentes seminal glands ejaculatory ducts Prostate bulbourethral glands By Soressa A (PhD) 51 1. Ductus deferens is the continuation of the duct of the epididymis Is about 45 cm has relatively thick muscular walls and a minute lumen, giving it a cord-like firmness. begins in the tail of the epididymis, at the inferior pole of the testis. Ascends posterior to testis, medial to the epididymis Penetrates the anterior abdominal wall via the inguinal canal crosses over the external iliac vessels hooking on inferior epigastric vessels and enters the pelvis. leaves the deep inguinal ring and passes along the lateral wall of the pelvis, where it lies external to the parietal peritoneum and crosses the ureter in the region of the ischial spine By Soressa A (PhD) 52 By Soressa A (PhD) 53 – The vas deferens then runs medially and downward on the posterior surface of the bladder – The terminal part of the vas deferens is dilated to form the ampulla of the vas deferens – The inferior end of the ampulla narrows down and joins the duct of the seminal vesicle to form the ejaculatory duct By Soressa A (PhD) 54 Arterial supply: – The tiny artery to the ductus deferens usually arises from a superior (sometimes inferior) vesical artery – terminates by anastomosing with the testicular artery, posterior to the testis. Venous drainage: – Veins drain into the testicular vein, including the distal pampiniform plexus – Its terminal portion drains into the vesicular/prostatic venous plexus Lymphatic drainage: Lymphatic vessels from the ductus deferens end in the external iliac lymph nodes By Soressa A (PhD) 55 2. Seminal glands Each seminal gland (vesicle): is a sacculated pouch about 5 cm long and 1 – 1.5 cm in diameter lies between the base (fundus) of the bladder and the rectum obliquely placed glands superior to the prostate do not store sperms, as their name implies. the superior ends of the seminal glands are covered with peritoneum lie posterior to the ureters, where the peritoneum of the rectovesical pouch separates them from the rectum the inferior ends of the seminal glands are closely related to the rectum and are separated from it only by the By Soressa rectovesical septum A (PhD) 56  – Consists of a single tube which is coiled upon itself and give off numerous irregular diverticulum – When uncoiled the tube is about 10 – 15 cm long and 3 to 4 mm in diameter – The duct of the seminal gland joins the ductus deferens to form the ejaculatory duct Relation: – Anteriorly: base of urinary bladder – posteriorly: rectum – Medially: ampulla of vas deferens – Laterally: fat on the pelvic surface the levator ani – Superioly: its upper end is covered by peritoneum of rectovesical pouchd By Soressa A (PhD) 57 Arterial supply: – The arteries to the seminal glands derive from: the inferior vesical artery middle rectal artery – Venous drainage: The veins accompany the arteries and have similar names Lymphatic drainage: – The iliac lymph nodes receive lymph from the seminal glands: the external iliac nodes from the superior part the internal iliac nodes from the inferior part By Soressa A (PhD) 58 Abscesses in the seminal glands – Localized collections of pus (abscesses) in the seminal glands may rupture, allowing pus to enter the peritoneal cavity. – Seminal glands can be palpated during a rectal examination, especially if enlarged or full. – They are palpated most easily when the bladder is moderately full By Soressa A (PhD) 59 3. Ejaculatory Ducts are slender tubes that arise by the union of the ducts of a seminal glands with the ductus deferenes approximately 2.5 cm long arise posteriorly near the neck of the bladder pass anteroinferiorly through the posterior part of the prostate and along the sides of the prostatic utricle The ejaculatory ducts converge to open on the seminal colliculus by tiny, slit-like apertures on, or just within, the opening of the prostatic utricle prostatic secretions join the seminal fluid in the prostatic urethra after the ejaculatory ducts have terminated By Soressa A (PhD) 60 Arterial supply: The arteries to the ductus deferens, usually branches of the superior (but frequently inferior) vesical arteries, supply the ejaculatory ducts Venous drainage: The veins join: – the prostatic venous plexuses – vesical venous plexuses Lymphatic drainage: The lymphatic vessels drain into the external iliac lymph nodes By Soressa A (PhD) 61 4. Prostate Shape: Coniccal in shape Dimensions: – Anteroposterior diameter: 2 cm – Vertical diameter: 3 cm – Transverse diameter: 4 cm is the largest accessory gland of the male reproductive system The glandular part makes up approximately two thirds of the prostate the other third is fibromuscular. The firm, walnut-size prostate surrounds the prostatic urethra. By Soressa A (PhD) 62 Relation Superiorly: – The base of the prostate is continuous with the neck of the bladder – the smooth muscle passing without interruption from one organ to the other – The urethra enters the center of the base of the prostate Inferiorly: – The apex of the prostate lies on the upper surface of the urogenital diaphragm – The urethra leaves the prostate just above the apex on the anterior surface Anteriorly: – related to the symphysis pubis, separated from it by the extraperitoneal fat in the retropubic space (cave of Retzius) – connected to the posterior aspect of the pubic bones by the fascial puboprostatic ligaments By Soressa A (PhD) 63  Posteriorly: – related to the anterior surface of the rectal ampulla – is separated from it by the rectovesical septum (fascia of Denonvilliers) – this septum is formed in fetal life by the fusion of the walls of the lower end of the rectovesical pouch of peritoneum, which originally extended down to the perineal body. Laterally: – The prostate is embraced by the anterior fibers of the levator ani as they run posteriorly from the pubis By Soressa A (PhD) 64 The fibrous capsule of the prostate: is dense and neurovascular Incorporates the prostatic plexuses of veins and nerves. All this is surrounded in turn by the visceral layer of the pelvic fascia: – forming a fibrous prostatic sheath that is thin anteriorly – continuous anterolaterally with the puboprostatic ligaments – dense posteriorly where it blends with the rectovesical septum By Soressa A (PhD) 65 The prostetic gland Has: a base: – Directed upward – closely related to the neck of the bladder – Pierced by urethra nearer to its anterior than posterior an apex: – in contact with pelvic fascia on the superior aspect of the urethral sphincter and deep perineal muscles. By Soressa A (PhD) 66 By Soressa A (PhD) 67 Four surfaces – Anterior surface (muscular) mostly transversely oriented muscle fibers forming a vertical, trough-like hemisphincter, which is part of the urethral sphincter separated from the pubic symphysis by retroperitoneal fat and venous plexus in the retropubic space Its upper part gives attachment to the puboprostatic ligament the urethra come out of this surface alittle infront and above the apex – Posterior surface: flattened related to the ampulla of the rectum the ejaculating ducts pass through its upper part By Soressa A (PhD) 68 – Two inferolateral surfaces Related to the anterior part of levator ani on each side Separated from the muscle by plexus of veins Lobes of the gland Four lobes: – Anterior lobe – Posterior lobe – Right and left lobes – Medial lobe By Soressa A (PhD) 69 Anterior lobe: The isthmus of the prostate (commissure of prostate) lies anterior to the urethra. It is fibromuscular, the muscle fibers representing a superior continuation of the urethral sphincter muscle contains little or no glandular tissue. The inferoposterior (posterior) lobe: lies posterior to the urethra and inferior to the ejaculatory ducts it is readily palpable by digital rectal examination contains glandular tissue The right and left (lateral) lobes: lie on either side of the urethra form the bulk part of the gland The lateral lobes contain many glands By Soressa A (PhD) 70 The middle (median) lobe: lies between the urethra and the ejaculatory ducts closely related to the neck of the bladder. project upwards and forwards to form uvula that may project into the internal urethral orifice By Soressa A (PhD) 71  Some authers divide the prostate into peripheral and central (internal) zones The central zone is comparable to the middle lobe. Within each lobe are four lobules, which are defined by the arrangement of the ducts and connective tissue. The prostatic ducts (20 to 30) open chiefly into the grooves, the prostatic sinuses, that lie on either side of the seminal colliculus on the posterior wall of the prostatic urethra By Soressa A (PhD) 72 By Soressa A (PhD) 73 By Soressa A (PhD) 74 Arterial supply: The prostatic arteries – mainly branches of the internal iliac artery – especially the inferior vesical arteries – also the internal pudendal and middle rectal arteries Venous drainage: The veins join to form a plexus around the sides and base of the prostate This prostatic venous plexus, between the fibrous capsule of the prostate and the prostatic sheath: – drains into the internal iliac veins. The prostatic venous plexus: – continuous superiorly with the vesical venous plexus – communicates posteriorly with the internal vertebral venous plexus. Lymphatic drainage: – The lymphatic vessels terminate chiefly in the internal iliac lymph nodes, but some drainageBymay Soressa Apass (PhD) to the sacral nodes 75 Hypertrophy of the Prostate The prostate is of considerable medical interest because enlargement or benign hypertrophy of the prostate (BHP), is common after middle age, affecting virtually every male who lives long enough An enlarged prostate projects into the urinary bladder and impedes urination by distorting the prostatic urethra The middle lobe usually enlarges the most and obstructs the internal urethral orifice the more the person strains, the more the valve-like prostatic mass occludes the urethra. BHP is a common cause of urethral obstruction, leading to nocturia (need to void during the night), dysuria (difficulty and/or pain during urination), and urgency (sudden desire to void) BHP also increases the risk of bladder infections (cystitis) as well as kidney damage The prostate is examined for Byenlargement Soressa A (PhD) and tumors (focal masses 76 or asymmetry) by digital rectal examination  The prostate is examined for enlargement and tumors (focal masses or asymmetry) by digital rectal examination The palpability of the prostate depends on the fullness of the bladder A full bladder offers resistance, holding the gland in place and making it more readily palpable The malignant prostate feels hard and often irregular In advanced stages, cancer cells metastasize both: – via lymphatic routes (initially to the internal iliac and sacral lymph nodes and later to distant nodes) – via venous routes (by way of the internal vertebral venous plexus, to the vertebrae and brain). By Soressa A (PhD) 77 By Soressa A (PhD) 78 Innervation of the internal genital organs of the male pelvis The ductus deferens Seminal glands Ejaculatory ducts Prostate are richly innervated by sympathetic nerve fibers Presynaptic sympathetic fibers originate from cell bodies in the intermediolateral cell column of the T12 - L2 (or L3) spinal cord segments They traverse the paravertebral ganglia of the sympathetic trunks to become components of: – lumbar (abdominopelvic) splanchnic nerves – the hypogastric and pelvic plexuses. Presynaptic parasympathetic fibers asise from S2 and S3 spinal cord segments traverse pelvic splanchnic nerves, which also join the By Soressa A (PhD) 79 inferior hypo-gastric/pelvic plexuses  Synapses with postsynaptic sympathetic and parasympathetic neurons occur within the plexuses end route to or near the pelvic viscera As part of an orgasm, the sympathetic system stimulates rapid peristaltic-like contractions of the ductus deferens, and the combined contraction of and secretion from the seminal and prostate glands provides the vehicle (semen) and the expulsive force to discharge the sperms (L. spermatozoa) during ejaculation. The function of the parasympathetic innervation of the internal genital organs is unclear However, parasympathetic fibers traversing the prostatic nerve plexus form: – the cavernous nerves that pass to the erectile bodies of the penis, which are responsible for producing penile erection. By Soressa A (PhD) 80 THANK YOU! By Soressa A (PhD) 81