Kidneys

• Lie retroperitoneally on posterior abdominal wall
• Right (pushed down by liver) 1/2inch lower than left
• Internal: Calyces split into minor calyces
• Fascia: Perinephric fat, renal fascia (of Gerota), paranephric fat
• Blood supply: renal artery (L3)
• Venous drainage: renal veins (in front of artery, crosses aorta on left - can cause varicocoele)
• Lymph drainage: Para aortic nodes

Relations:

1. Posteriorly:
   • Muscles: diaphragm (separating pleura), quadratus lumborum, psoas, transversus abdominis
   • Bones: 12th rib
   • Structures: T12 (subcostal nerve), iliohypogastric nerve, ilioinguinal nerve (L1)
2. Anteriorly:
   • Right: Liver, 2nd part of duodenum, ascending colon
   • Left: spleen, pancreas, stomach, descending colon
3. Medially:
   • Hilum: A-P - Vein, artery, ureter, lymphatics

[Nephrectomy]

Ureter

• 25cm long
• Blood supply: segmental b/s from all available arteries along course - aorta, renal, testicular, internal iliac, inferior vesicle
• Sites of relative narrowing: (1) junction of pelvis of ureter with abdominal part (2) pelvic brim (3) ureteric orifice
• Radiographic course: tips of transverse processes, crosses SIJ, swings out to ischial line and passess medially to bladder

1. Abdominal ureter
   • Lies on medial edge of psoas major (along tips of transverse process of L2-L%)
   • Crosses pelvic brim at bifurcation of common iliac artery in front of sacroiliac joint
   • Crossed by gonadal vessels
2. Pelvic ureter
   • Runs on lateral wall of pelvis in front of internal iliac artery
   • Turns forwards and medially to enter bladder
   • In male: lies above seminal vesicle, crossed superficially by vas deferens
   • In female: passes above lateral fornix of vagina, lies below broad ligament
3. Intravesical ureter
   • Passess obliquely through wall of bladder for 2cm

Bladder

• Intra-abdominal but extraperitoneal
• Neck of bladder fuses with prostate in male
• Muscle coat of bladder formed by criss-cross arrangement of bundles, undergoes hypertrophy in chronic obstruction (due to enlarged prostate); circular component of muscle coat condenses as an (involuntary) interal urethral sphincter around the internal orifice (which can be destroyed withrout incontinence providing the external sphincter remains intact).
• Blood supply: superior / inferior vesical branches of internal iliac artery
• Venous drainage: plexus into internal iliac vein
• Nerve supply: (1) Parasympathetic fibres S2-S4: Motor to muscle wall, inhibitory to internal sphincter (2) Sympathetic (3) pudendal nerve to external striated muscle sphincter [Micturition]

Relations

1. Anteriorly:
   • Pubic symphysis
2. Superiorly:
   • Covered by peritoneum with coils of small intestine and sigmoid colon
   • In female: body of uterus flops over the top
3. Posteriorly:
   • Male: rectum, seminal vesicles
   • Female: vagina, supravaginal part of cervix
4. Laterally:
   • Levator ani and obturator internus

Interior of bladder

• Trigone formed from 2 ureteric orifices and urethral opening
• Bladder mucosa thrown into folds when bladder is empty - smoothing out during distention

Urethra

• 20cm in the male

1. Prostatic urethra

   

   • 3cm
   • Transverses prostate
   • Posterior wall bears longitudinal elevation called the urethral creast
   • On each side is a shallow depression called the prostatic sinus (prostatic ducts empty)
   • At middle of urethral crest is prominencecalled the colliculus seminalis (verumontanum) into which opens the prostatic utricle (male equivalent of the vagina)
   • On either side of orifice of prostatic utricle open the ejaculatory ducts
2. Membranous urethra
   • 2cm pierces external sphincter urethrae (voluntary sphincter of the bladder)
3. Spongy urethra
   • Transverses the corpus spongiosum of penis
   • Passes upwards and forwards to lie below pubic symphysis