Urinary Tract

Front 1

location, relationships, features and neurovascular supply of the kidneys

Back 1

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Front 2

relationship of the renal fascia to the kidneys and suprarenal glands

Back 2

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Front 3

• Define the term end artery and explain the significance of this with respect to the segmental arteries of the kidneys

Back 3

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Front 4

structure, length, course and relationships of the ureters including relationship to the peritoneum

Back 4

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Front 5

locations of the 3 constriction points along the ureter and the relationship of these to ureteric colic

Back 5

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Front 6

location and relationships of the bladder, its internal and external features and neurovascular supply

Back 6

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Front 7

location and shape of the bladder in a newborn and adult

Back 7

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Front 8

the range of developmental anomalies related to kidney, ureter and bladder development

Back 8

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Front 9

Compare and contrast the urethra in both sexes and describe the location and innervation of the urethral sphincters

Back 9

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Front 10

Urinary Tract; 2 sections

Back 10

Front 11

UTIs

Back 11

Cystitis: lower (commonly called UTI)
Polynephritis: upper UTI

Front 12

Kidneys - Size

Back 12

Size approximately 10 x 5 x 2.5 cm, retroperitoneal, right kidney lower than left, tilted in 2 planes (superior poles closer; anterior surfaces slightly lateral)

Front 13

Kidneys - Location

Back 13

Front 14

Kidneys: Layers

Back 14

1. kidney
2. Thin fascia
3. perinephric fat
4. renal fascia (tight superior at the diaphragm fascia and loose inferiorly)
5. Paranephric fat

Front 15

Functions of the Kidney Layers

Back 15

The fat and fascia help to maintain the position of the kidney
Loss of supporting fat (eg. anorexia)  renal ptosis with potential kinking of ureters  hydronephrosis
Kidneys move vertically during respiration & when moving from supine to upright position
Attachments of renal fascia determines direction of spread of infection (renal abscess) & blood (injury)  spreads inferiorly due to loose attachment of anterior & posterior layers of renal fascia inferior to kidney

Front 16

Kidneys – External Features

Back 16

Renal capsule (dense, fibrous, glistening appearance) on surface of kidney, extends into renal sinus

Renal hilum is a 1 cm long cleft on medial border through which structures enter/exit, it leads into the renal sinus Structures passing through hilum include renal artery and vein, renal pelvis, nerves and lymphatics

Front 17

Neurovascular Supply Kidney

Back 17

Ant. to Post.
1. Renal v.
2. renal a.
3. renal pelvis

Front 18

Kidneys – Internal Features

Back 18

- Renal cortex around periphery; it extends between pyramids as the renal columns
- Renal medulla = collection of renal pyramids
- Renal pyramids contain collecting tubules which open at renal papilla (apex of pyramid)
- Renal papilla indents each minor calyx
- Minor calyces join to form major calyces
- 2-3 major calyces join to form renal pelvis
- Renal pelvis is funnel-shaped, it narrows to form ureter

Front 19

Kidneys Internal Macrscopic Look

Back 19

Front 20

Kidneys – Blood supply

Back 20

Left & right renal arteries are branches of the abdominal aorta (L2 level) and receive ~20-25% cardiac output
Lie posterior to the renal veins. The right renal artery passes posterior to the IVC
Accessory renal artery is present in ~30% of population; usually a branch of the abdominal aorta
Left & right renal veins drain to IVC. Left renal vein receives the left suprarenal vein and left gonadal vein
Left renal vein passes in angle between the SMA & abdominal aorta and can be prone to entrapment (Nutcracker syndrome). This may cause haematuria, left flank pain and maybe a cause of left-sided varicocoele and/or left testicular pain

Front 21

Nutcracker Syndrome

Back 21

Front 22

Accessory renal artery

Back 22

Front 23

Kidney BS to the panrynchyma

Back 23

Front 24

Kidney End Arteries

Back 24

Consequently blockage of a segmental artery (e.g., embolus from the left side of the heart)  necrosis of that segment of kidney (renal infarction)

Front 25

Kidneys - Relationships

Back 25

Anterior relations
Left kidney: suprarenal gland, colon, jejunum, stomach, spleen, pancreas
Right kidney: suprarenal gland, colon, jejunum/ileum, duodenum, liver

Posterior relations
4 muscles - diaphragm, psoas major, quadratus lumborum, aponeurosis of transversus abdominis; 12th rib post to right kidney; 11th & 12th rib post to left kidney (# ribs  damage to kidney  blood in urine); 3 nerves (subcostal, iliohypogastric, ilioinguinal - potential damage with kidney surgery); subcostal artery & vein

Front 26

Posterior Kidney relations

Back 26

Front 27

Anterior Kidney Relations

Back 27

Front 28

Enlarged left kidney vs. Enlarged spleen

Back 28

•Kidney retroperitoneal and can feel space between enlarged kidney & costals
•Kidney moves inferiorly with inspiration, but spleen moves obliquely (towards umbilicus)
•Percussion usually resonant over kidney (due to gas in overlying bowel) but dull over spleen
•Notched border of spleen may (or may not) be palpable

Front 29

Kidney Transplant

Back 29

•Donor kidney transplanted  iliac fossa (extraperitoneal)
•Donor’s renal artery & vein connected to external iliac vessels, ureter connected to bladder
•Patient’s kidneys usually remain in place

Front 30

Ureters

Back 30

Ureters 25 cm long, expansible tubes of smooth muscle; 3-5 mm wide; extend from renal pelvis to bladder; upper ½ in abdominal cavity, lower ½ in pelvic cavity; midpoint crosses pelvic brim anterior to bifurcation of common iliac artery; passes obliquely through bladder wall; ends at ureteric orifice in urinary bladder

Front 31

BS of ureters

Back 31

Blood supply From adjacent arteries, which anastomose along ureter

Front 32

Ureters – Course

Back 32

Abdominal course: retroperitoneal; almost vertical on psoas major, crossed anteriorly by gonadal vessels
Pelvic course: extraperitoneal; from pelvic brim passes posterolaterally on pelvic wall, then at level of ischial spine turns medially and anteriorly towards bladder
“Water under the bridge” in male & female; “bridge” = ductus deferens in male; uterine artery in female

Front 33

Ureters: Radiographically
- before a CT scan lookinf for colic

Back 33

In searching for a ureteric stone on a plain radiograph of the abdomen, one must imagine the course of the ureter in relation to the bony skeleton. It lies along the tips of the transverse processes, crosses in front of the sacroiliac joint, swings out to the ischial spine and then passes medially to the bladder. An opaque shadow along this line is suspicious of calculus. This course of the ureter is readily studied by examining a radiograph showing a radio-opaque ureteric catheter in situ.

Front 34

Ureters Constriction Points

Back 34

3 sites of constriction/narrowing along ureter where ureteric calculus may lodge.
 +/- ureteric colic (loin to groin pain);  +/- hydroureter and hydronephrosis (with progressive renal parenchymal damage)

Front 35

Hydroureters or Hydronephrosis

Back 35

Front 36

Development – Kidneys, Ureter
Some congenital anomalies of kidneys and ureters

Back 36

Front 37

Urinary Bladder
Internal features:

Back 37

Rugae - folds of mucous membrane in empty bladder that disappear as bladder distends
Trigone - triangular area situated posteriorly limited by 2 ureteric orifices and an internal urethral orifice
An interureteric ridge/crest extends between the ureteric orifices

Front 38

Coronal section through bladder in male

Back 38

Front 39

Bladder – Relationships in Female

Back 39

Anterior - retropubic space and pubic bone/pubic symphysis
Superior - coils of intestines and body of uterus
Inferolateral - levator ani & obturator internus
Posterior - cervix of uterus and vagina (not rectum)

Front 40

Bladder – Relationships in Male

Back 40

Anterior - retropubic space and pubic bone/pubic symphysis
Superior - coils of intestines
Inferolateral - levator ani (is a part of pelvic diaphragm) & obturator internus
Inferior - prostate
Posterior - rectum, ductus deferens, seminal vesicles

Front 41

Urethra - Female

Back 41

-Female urethra commences at internal urethral orifice at neck of bladder,
-Ends at external urethral orifice (in the vestibule of vagina between vaginal opening and clitoris).
-Approximately 4 cm long, passes anteriorly and inferiorly (important to understand for catheterisation),
-Passes through pelvic diaphragm, surrounded by external urethral sphincter (skeletal muscle, voluntary)
-Urethra is short; therefore females are prone to lower urinary tract infections

Front 42

Urethra – Male

Back 42

- Male urethra commences at internal urethral orifice at neck of bladder, ends at external urethral orifice
- 4 parts: preprostatic (through bladder neck; surrounded by sphincter vesicae); prostatic (~3 cm); membranous (~ 1cm; though sphincter urethrae and perineal membrane); spongy or penile (~15 cm, corpus spongiosum & glans penis).
- The prostatic part (widest & most dilatable part) has an elevation (seminal colliculus) that receives openings of the ejaculatory ducts and utricle

Front 43

Micturition
4 components

Back 43

1. Sympathetic nerves are excitatory to smooth muscle of bladder base, neck & proximal urethra & have an inhibitory effect
2. Visceral afferents detect bladder stretch; stretch information travels with pelvic splanchnic nerves  S2-4 segments of spinal cord  connections to higher centres  desire to micturate. Micturition inhibited by higher centres until a convenient time. NOT YET DEVELOPED IN CHILDREN
3. Parasympathetic fibres travel via pelvic splanchnic nerves  contraction of detrusor muscle and relaxation of sphincter vesicae.
4. Voluntary component of bladder emptying involves relaxation of pelvic diaphragm & sphincter urethrae. Higher centres do not control micturition until 2-3 years, prior to this bladder empties reflexly

Front 44

Micturition Process

Back 44

Front 45

X-rays

Back 45

- plain radiograph
- radiograph + contrast
- CT scan
- CT + Contrast

Front 46

Contrast media

Back 46


negative agents

air

carbon dioxide
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positive agents

iodine-containing water-soluble media e.g. iohexol, iopamidol
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barium
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oily media

Front 47

Back 47

stag horn calculus (not contrast medium)

Front 48

Nuclear Medicine

Back 48

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DMSA – taken up by functioning tubules
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DTPA, MAG3 – filtered and concentrated by kidney in the same way as radiographic, CT and MRI contrast media
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graphical recording with time on y-axis & activity on x-axis

Front 49

Ultrasound and Doppler

Back 49

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sound reflected back from tissue interfaces
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time difference indicates distance of interface
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Doppler ultrasound used to measure blood flow
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safe so usually the first diagnostic imaging test

Front 50

Nuclear magnetic resonance

Back 50

magnetism and radio-frequency waves
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images show multiple different tissue characteristics
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contrast media based on Gd-DTPA behave like x-ray CT contrast media
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NMR spectroscopy identifies chemical constituents

Front 51

Back 51

Horseshoe kidney

Front 52

Relation to skeleton

Back 52

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kidney L1 to umbilicus
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covered by 12th rib
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3 vertebral bodies long in the adult

about 9-13 cm long

left usually lies slightly superiorly to right (because of liver)

Front 53

Orientation of kidneys

Back 53

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lower pole anterior to upper pole
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lower pole lateral to upper pole
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hilum anteromedial

Front 54

Variations in position of kidney

Back 54

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normal respiratory movement
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ptotic or pelvic kidney
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malrotated kidney
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horse-shoe kidney
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duplicated ureter

Front 55

Relations with other organ

Back 55

Front 56

Retroperitoneal fascial spaces

Back 56

Front 57

Lobar anatomy

Back 57

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embryological origin from many lobes (like a bunch of grapes)
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progressive fusion of lobes continues after birth
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foetal lobation or “lobulation” may persist on renal surface

Front 58

Kidney on ultrasound

Back 58


size easily measured

fat in renal sinus white
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medulla darker than cortex
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cortex darker than liver

collecting system normally collapsed
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blood vessels resemble collecting system unless colour Doppler US turned on

Front 59

Multiple renal arteries on catheter angiogram

Back 59

Front 60

Nephrogram phase of intravenous pyelogram (IVP)

Back 60

tomogram using a moving x-ray tube and film to blur overlapping structures – now replaced by CT

Front 61

Pyelogram phase of IVP

Back 61

Front 62

DMSA scintigram

Back 62

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DMSA binds to renal tubular cells
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maps normal functioning kidney

Front 63

DTPA scintigram

Back 63

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injected bolus circulates to whole of body
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first pass through kidney monitored
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injected agent clears to

interstitial fluid throughout body

urine

Front 64

Ureters – posterior to anterior

Back 64

Front 65

Bladder US

Back 65

Front 66

Prostate gland Imaging

Back 66

Front 67

Male urethra

Back 67

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prostatic part

membranous

external sphincter

bulbourethral glands
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bulbar urethra
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penile urethra

Front 68

lymph angeogram (oil filled contrast)

Back 68