Reproductive System PDF

lOMoARcPSD|44175252 Portal Vein - Drains blood from the abdominal GI tract, spleen, pancreas - Takes venous blood to the liver for metabolism - Metabolised blood drains into the hepatic veins, which drains into the IVC FEMALE REPRODUCTIVE SYSTEM PELVIC DIAPHRAGM - Separates pelvis and...

lOMoARcPSD|44175252 Portal Vein - Drains blood from the abdominal GI tract, spleen, pancreas - Takes venous blood to the liver for metabolism - Metabolised blood drains into the hepatic veins, which drains into the IVC FEMALE REPRODUCTIVE SYSTEM PELVIC DIAPHRAGM - Separates pelvis and perineum (area superficial to the pelvic diaphragm) - Attachment point for external genitalia - Diamond shaped with 2 triangles: o Urogenital triangle = anterior, has the urogenital hiatus (opening for urogenital system) o Anal triangle = posterior, has the anal aperture (opening for GI tract) - Formed by levator ani muscle (contracts to elevate the anus): o Puborectalis § Attaches to the pubis bone and goes around the rectum § Forms a sling around the rectum (puts a kink in it) § Maintains faecal continence (as well as internal and external anal sphincters) o Pubococcygeus = lateral to puborectalis, attaches to pubis and coccyx bones o Iliococcygeus = lateral to pubococcygeus, attaches to the ilium and coccyx bones  lOMoARcPSD|44175252 Perineal Membrane - Cover ½ of the pelvic diaphragm (urogenital triangle) - Superficial to the pelvic diaphragm - Opening for the urethra (M and F) and vagina (F) Deep Perineal Pouch - Space between perineal membrane and levator ani - Contains skeletal muscles that form voluntary sphincters around the urethra (external urethral sphincter) and the vagina  lOMoARcPSD|44175252 Child Birth - Perineum, levator ani (mostly puborectalis and pubococcygeus), perineal membrane and deep perineal pouch muscles are often torn/injured - In females, these muscles support the urethra, vagina, uterus and rectum - Injury can result in urinary stress incontinence, uterine prolapse and faecal incontinence INTERNAL GENITALIA Ovary - Paired - Intraperitoneal - Located posterior to the broad ligament and adjacent to the lateral wall of the pelvis - Ovarian artery = principle blood supply, branch of the abdominal aorta - Ligament of ovary = attaches ovary to uterus - Irregular shaped ball - 2 regions: o Inner medulla — holds vessels, nerves and lymphatics o Outer cortex — where follicular genesis occurs - Defined surface epithelium - Oocytes are surrounded by supporting cells, which prepare the oocyte for ovulation - Oocyte ovulates in the ovary and is expelled into the fallopian tube  lOMoARcPSD|44175252 Fallopian/Uterine Tubes - Project laterally from the uterus and open adjacent to ovaries - 3 areas o Infundibulum § Funnel shaped § Facilitates oocyte collection § Fimbriae = finger-like projections, attach to the anterior and lateral part of the ovary, help catch the oocyte o Ampulla § Large § Labyrinthine lumen § Fertilization occurs in the ampulla o Isthmus § Narrow § Connects to uterus Uterus - Thick walled, muscular - Facilitates development of the embryo and foetus - Uterine artery = supplies uterus, from internal iliac artery - 3 parts: o Fundus = top part, above fallopian tubes o Body = largest part, below fallopian tubes o Cervix = opening into vagina - 2 linings: o Myometrium = middle layer made of smooth muscle, during pregnancy it undergoes hypertrophy and hyperplasia o Endometrium = inner lining, supports pregnancy (zygote implants in endometrium), sheds during menstruation o Position of uterus (when the bladder s empty): o Anteverted (AV) relative to the vagina o Anteflexed (AF) over the bladder o When the bladder s full, uterus is displaced upwards o Retroverted and retroflexed = uterus displaced to the back, more likely to prolapse o Uterine prolapse = uterus pushed through the vagina due to high pressure in the pelvis  lOMoARcPSD|44175252 Cervix - Opens inferiorly into the anterior wall of the vagina - 2 parts: o Supravaginal (above vagina) o Vaginal (in vagina) - Uterus is best supported at the cervix Vagina - Muscular passage - Connects uterus to the exterior - Between the urethra anteriorly and rectum posteriorly - Fornix = spaces created anterior, posterior and lateral to where the cervix enters the vagina - Vaginal arteries = supplies vagina, branch of internal iliac artery  lOMoARcPSD|44175252 ECTOPIC PREGNANCY - Fertilization occurs in the ampulla - Implantation usually occurs in the uterine body - Ectopic/extrauterine pregnancy = implantation occurs anywhere but the endometrial lining - If an ectopic pregnancy occurs in an area with a large blood supply, the embryo will grow - Causes bleeding into the abdominal cavity - Burst uterine tube from ectopic pregnancy is often misdiagnosed as a burst appendix PERITONEAL FOLDS - Peritoneum = serous membrane covering the top of the pelvic viscera - Supports and protects the pelvis - Peritoneal folds form over the pelvic viscera - Broad ligament = peritoneal folds coming together over the uterine tube - Ovaries are surrounded by peritoneum and therefore are intraperitoneal (there is an opening for the oocyte to pass through) - Ligament of ovary = folds of peritoneum over the ovarian vessels Peritoneal Pouches - Created by peritoneal folds - Recto-uterine pouch o Between the rectum and uterus o Deepest part of the abdominal cavity o Fluid collects here, especially if patient lies on their back o Fluid can be aspirated with a syringe through the fornix - Vesico-uterine pouch = between the bladder and uterus  lOMoARcPSD|44175252 EXTERNAL GENITALIA Development of external genitalia - Same in M and F - Genital tubercle à glans penis (M) or glans clitoris (F) - Testosterone causes more rapid growth of the genital tubercle, resulting in it being larger in males - Urethral folds à urethra (M and F) and labia minors (F) - Labioscrotal swellings à scrotum (M) and labia majora (F) Anatomy - Vulva/pudendum = erectile tissue and overlying skin which comprises the external genitalia - Labia minora = 2 thin skin folds next to the midline, fat free and hair free with connective tissue inside - Vestibule = area between each labia minora (contains urethra and vagina) - Labia majora = larger skin folds, lateral to labia minora - Glans clitoris = erectile tissue, exposed (not covered by skin), located where the labia minora meet anteriorly - Perineal membrane and pubic arch = attachment point for the roots of external genitalia  lOMoARcPSD|44175252 Erectile Tissue - Erectile tissue is formed by: o 2 corpora cavernosa (located anterior to glans clitoris, attach to pubic arch) o 2 bulbs of vestibule (located deep to labia minora) o Glans clitoris - Body of clitoris = corpora cavernosa and bulbs of vestibule - Erectile tissues are anterior to the urethra - Greater vestibular glands = posterior to bulbs, have openings into the vestibule, secretes lubricating mucous during arousal Muscles - Ischiocavernosus muscle = covers crus of clitoris (part of corpora cavernosa attaching to the pubic arch) and maintains erection of the clitoris - Bulbospongiusis muscle = encloses the bulbs and greater vestibular glands, supports the pelvic floor, assists in clitoral erection and compresses greater vestibular glands  lOMoARcPSD|44175252 MALE REPRODUCTIVE SYSTEM PELVIC DIAPHRAGM - Same as female pelvic diaphragm - Only 1 opening in the perineal membrane for the urethra - Deep perineal pouch also has sphincters around glands PERINEAL MEMBRANE o Superficial to pelvic diaghragm o Covers urogenital triangle o Opening for urethra (male & female) and vagina (female) DEEP PERINEAL POUCH o Space above the perineal membrane o Contains skeletal muscle that form sphincters around the urethra, glands, & neurovascular structures that supply the penis  lOMoARcPSD|44175252 INTERNAL GENITALIA Testes - Function in sperm production - Septa (connective tissue) divides the testes into ~250 lobules - Lobules contain 3-10 seminiferous tubules (where spermatogenesis occurs) - Each tubule is a highly convoluted loop in the lobule - The closer to the lumen, the more the sperm differentiate (still non-motile though) - In the mediastinum, tubules end as tubulus erectus (straight tube), which connects to the rete testis - Rete testis = anastomosing channel system, collects sperm from all the seminiferous tubules - Outer capsules o Tunica albugenia = surrounds lobules o Tunica vaginalis = covers testes during descent, extension of abdominal peritoneum, surrounds tunica albugenia Testicular decent o Gonadal development occurs along posterior abdominal wall o Testes desced towards inguinal canal by 7 months gestation o Through inguinal canal into scrotum just before birth o Drags blood vessels, nerves, duct system (vas deferens) and layers of abdominal wall to scrotum Cryptorchidism (undescended testes) o Histological changes à infertility o Increased risk of testicular cancer o Needs to be surgically corrected preferentially before 18 months / 2 years of age  lOMoARcPSD|44175252 Epididymis - Coiled tube - about 5cm long - Sperm in the mediastinum of the testes travel through efferent tubules to the epididymis - Capus = head - Corpus = body - Caudal = tail - Surrounded by smooth muscle to assist movement of sperm - Function to store and mature sperm - Where sperm acquire motility - Sperm are stored for ~1 month in the epididymis, before they die and are reabsorbed by epithelial cells Vas Deferens - Sperm travels from the epididymis to the vas deferens - Long duct - Length and complex course results from testicular descent - Penetrates abdominal wall through the inguinal canal - Descends along the lateral wall of the pelvic cavity - Wolffian ducts à vas deferens - Smooth muscular duct (inner circular and outer longitudinal muscles) - Muscular duct (smooth muscle wall) which transports spermazoa to ejaculatory duct - Ejaculation is mediated by the sympathetic NS, and causes the smooth muscle to contract and pump sperm through it - Ejaculatory duct = vas deferens and duct of seminal vesicle - Function is to transport sperm to ejaculatory duct - Part of the spermatic cord Vasectomy - Ligating the vas deferens to prevent sperm from reaching the penis - Vas is superficial at the posterior side of the scrotum, allowing the procedure to be relatively non- invasive - White blood cells assist the epididymis to break down sperm after a vasectomy  lOMoARcPSD|44175252 Accessory Glands Contribute to the volume of ejaculate. Each has different secretion with different functions Seminal vesicles, prostate and bulbourethral glands Seminal Vesicles o Located at the posterior surface of the bladder o Ducts of seminal vesicle combines with vas deferens to form the ejaculatory duct, which empties into the prostatic urethra o Contributes to the volume of semen o Secretes an alkaline, viscous fluid, which neutralizes the acidic female reproductive tract o Contributes to sperm motility and viability Prostate o Inferior to the bladder, anterior to the rectum, superior to the perineal membrane, surrounds the urethra o About the size of a walnut o 3 zones: peripheral, transitional and central o Secretes water like liquid containing zinc, citric acid, prostaglandins and proteolytic enzymes o Assists with sperm viability and maturation o Many openings from prostate into the prostatic urethra Benign Hypertrophy of the Prostate o Occurs in most elderly men o Hypertrophy of the central prostate o Compresses/blocks the urethra giving an intermitted urinary stream o Direct rectal examination (DRE) reveals a large and bulky prostate (feels soft as the centre is effected) Prostate Cancer o Common malignancy in men o 70% are in the peripheral region o Effects the entire prostate o Diagnosed by DRE (prostate feels rock hard) or blood test o Treated with radiotherapy, chemotherapy, removal or androgen deprivation therapy o If androgen dependent, androgen deprivation therapy will shrink/remove the tumour o If tumour reoccurs, it is not androgen dependent and will be more aggressive  lOMoARcPSD|44175252 Bulbourethral Glands - Paired - Pea shaped - Located in the deep perineal pouch - Ducts open into spongey urethra - Mucous type secretion which lubricates the urethra - Forms pre-ejaculate DEVELOPMENT OF EXTERNAL GENITALIA  lOMoARcPSD|44175252 HYPOSPADIAS o Congenital disorder of the penis o Urethra opens somewhere along the shaft of the penis - 1:250 boys EXTERNAL GENITALIA - Erectile tissues covered by skin - Body of penis = pendulous and entirely surrounded by skin - Scrotum o Homologue of labia majora o Skin fuses in the midline (raphe) o Testes descend into this pouch - Prepuce = skin covering glans penis, open anteriorly, attaches to glans penis at the frenulum - Perineal membrane and pubic arch = attachment points for roots of penis  lOMoARcPSD|44175252 Penis - Covered by skin - Perineal membrane and pubic arch = attachment roots of penis - Erectile tissues comprise: o 2 corpora cavernosa o 1 corpus spongiosum o Corpus spongiosum expands distally to form glans penis - Urethra pierces the perineal membrane through the urogenital hiatus, then enters the corpus spongiosum and opens at the glans penis - Erection is mediated by the parasympathetic NS, causing arteries in the penis to relax which allows blood to fill erectile tissues 3 cylinders of erectile tissues o 2 corpora cavernosa o 1 corpus spongiosum, encloses penile urethra o Each cylinder contains trabecular network of veins surrounded by collagen, elastic fibers & smooth muscle cells Erectile dysfunction in male and female o Two corpora cavernosa (male and female) o A single corpus spongiosum in male; two bulbs of vestibule in female Penis o Erection is mediated by parasympathetic nervous system, which relaxes arteries in penis, allowing blood to fill erectile tissues Muscles = ischiocavernosis muscle and bulbospongiosus muscle move blood from the root of the penis to the body of the penis, and constrict venous drainage  lOMoARcPSD|44175252 KIDNEYS AND URINARY SYSTEM KIDNEYS - Adrenal glands are superomedial to each kidney - Function to produce urine - Paired solid viscus - Retroperitoneal - Bean shaped (10x2x2.5cm) - Healthy kidneys are red/brown coloured - Extends longitudinally from T12-L3 - Closely associated with the diaphragm à position changes with contraction of the diaphragm - Left kidney higher than the right as the liver pushes it lower - 2 surfaces: anterior surface and posterior surface (sits against quadratus lumborum) - Approach to operate on the kidneys is laterally or posteriorly due to their positioning Perinephric Fat and Renal Fascia - Perinephric fat = fat surrounding the kidneys - Renal fascia = lines of perinephric fat and kidneys - Renal fascia and perinephric fat sit behind parietal peritoneum Kidney Structure - Renal capsule lines kidney surface - Renal sinuses = spaces within the kidney, filled with perinephric fat - Inner medulla o Renal pyramids = pyramid shaped structures (base at surface, apex towards hilum) o Consists of secretory cells (secretes urine) o Renal pyramids are separated by cortex  lOMoARcPSD|44175252 - Outer cortex o Continuous o Separates renal pyramids Renal Collecting System - Urine s secreted from the medulla - Secreted from the apex of the medulla into the hilum - Urine is collected into the minor calyx - 2-3 minor calices collect into a major calyx - 2-3 major calices collect into the renal pelvis (upper part of the ureter which passes through the renal hilum) Renal Hilum - Faces anteromedially (structures of the hilum feed into/arise from vessels anterior to the vertebral column, which is more anterior than the kidney) - Holds the renal vein (front), renal artery (middle) and renal pelvis (back) as well as nerves and lymphatics Renal Artery - Principle blood supply to each kidney - Arises from the paired branches of the abdominal aorta - Divides into 5 segmental arteries once it enters the hilum - Each segmental artery supplies a renal segment (single functional unit, typically 5, surgically resectable)  lOMoARcPSD|44175252 Accessory Renal Artery - Additional blood supply - Arise from development as the kidneys develop lower in the posterior abdominal wall - Different growth rates of the kidneys and the abdominal wall causes them to move up - Sometimes the original blood supply remains as well as new blood supply (renal artery) - Not present in everyone, or on both sides - Can enter the kidney via the hilum or the surface Renal Vein - Drains venous blood of the kidneys directly into the IVC - IVC is to the right of the abdominal aorta (in the midline) - Left renal vein crosses the midline before draining into the IVC and has a longer course than the right renal vein URETERS - Urine from kidneys passes into ureters - Paired hollow viscus - Extends from the kidneys into the pelvis - Begins at the renal hilum as the renal pelvis, passes inferiorly in front of psoas major and the lumbar vertebra transverse processes, crosses the pelvic brim and enters the bladder - Constrictions o Uretropelvic Junction = where the renal pelvis meets the ureter there is a narrowing o Where the ureter crosses the pelvic brim o Where the ureter obliquely traverses the muscular bladder wall (functional sphincter, prevents reflux of urine) - Constrictions pose an issue for kidney stones  lOMoARcPSD|44175252 URINARY BLADDER - Hollow viscus - Strong muscular walls with large muscular ridges - Function to store urine - Pyramid shaped o Base posteriorly, against uterus in females and rectum in males o Apex anteriorly, against pubis bone in males and females - Anteriormost pelvic viscus Bladder Neck - Inferiormost part - Achors the bladder, held by ligaments - As the bladder fills, the top part expands and is free, but the neck stays put Base - 3 openings forming an inverted triangle (trigone) - 2 uretric orifices = where the ureters enter the bladder - Urethral orifice = internal urethral opening - Surface of the trigone lacks muscular ridges and is smooth  lOMoARcPSD|44175252 URETHRA Passes urine from the bladder to the exterior. Female Urethra - Short - Exits the bladder, quickly passes through the pelvic floor and perineal membrane - Females are more susceptible to UTIs as it is short - Easy to insert a catheter Male Urethra - Long - Bends twice - 4 parts: o Preprostatic Part = immediately after bladder, before the prostate o Prostatic Part = traverses the prostate o Membranous Part = traverses the pelvic floor and perineal membrane o Spongey Part = runs inside the penis (both bends are in the spongey part) - Males less prone to UTI s due to length - Difficult to insert a catheter