Anatomy: Upper Urinary Tract Flashcards
Define the urinary tract
The anatomical structures through which urine passes from its production to its excretion from the body
List the 4 main contents of the urinary system
Kidneys (bilateral)
Ureters (bilateral)
Bladder
Urethra
What is the function of the 4 main contents of the urinary system? Kidneys (bilateral) Ureters (bilateral) Bladder Urethra
Kidneys (bilateral): produce urine
Ureters (bilateral): drains urine from the kidneys to the bladder
Bladder: stores urine and voids it into the urethra
Urethra: excretes urine (and semen in males)
Out of the 4 main contents of the urinary system, which are part of the upper and which are part of the lower urinary tracts? Kidneys (bilateral) Ureters (bilateral) Bladder Urethra
The upper urinary tract = the kidneys + the ureters
The lower urinary tract = the bladder + the urethra
An upper UTI may spread to the…?
Kidneys
A lower UTI involves the X and Y?
Bladder and urethra
The kidneys are found in the peritoneal cavity. T/F?
False
The kidneys are retroperitoneal organs. They are found in the abdominal cavity behind the peritoneum
Which parts of the urinary system are found in the... Abdomen Pelvis Perineum ...?
Abdomen: kidneys, proximal ureters
Pelvis: distal ureters, bladder, proximal urethra
Perineum: distal urethra
Imagine looking at an axial abdominal CT scan…
Name the 5 layers surrounding the anterior kidney
Visceral peritoneum Paranephric fat Renal (deep fascia) Perinephric fat Renal capsule
Briefly describe the 5 layers surrounding the anterior kidney: Visceral peritoneum Paranephric fat Renal (deep fascia) Perinephric fat Renal capsule
Visceral peritoneum: separates the kidneys from the peritoneal cavity
Paranephric fat: more anterior fat layer
Renal (deep fascia): separates the renal fat layers
Perinephric fat: liquid fatty layer in contact with the kidney
Renal capsule: tough fibrous tissue that completely encapsulates the kidney
Imagine looking at an axial abdominal CT scan…
Name the 3 abdominal wall muscles lying lateral to the kidneys
The anterolateral abdominal wall muscles:
- External oblique
- Internal oblique
- Transversus abdominis
Imagine looking at an axial abdominal CT scan…
Name the 2 abdominal wall muscles lying posterior/posteromedial to the kidneys
Right/left psoas major (posteromedial)
Right/left quadratus lumborum (posterior)
What 3 structures make up the renal hilum/root?
Renal artery
Renal vein
Ureter
Which structure lies... -Anteriorly -Posteriorly -Inferiorly ... in the renal hilum?
- Anteriorly: renal vein
- Posteriorly: renal artery
- Inferiorly: ureter
At what vertebral levels is the…
-Left kidney
-Right kidney
… found?
Left: T12-L2
Right: L1-L3
Why is the right kidney ~1 vertebral level lower than the left?
Due to the large size of the liver pushing the right one down
Which ribs are found posterior to the kidneys?
‘Floating’ ribs 11 and 12
Which abdominal quadrants are the kidneys located in?
Left: Left flank/LUQ
Right: Right flank/RUQ
Which abdominal regions are the kidneys found in?
Left: Left lumbar region/flank
Right: Right lumbar region/flank
Describe how ‘balloting’ of the kidney is carried out during clinical examination (use the right kidney as the example)
- One hand used to palpate posteriorly in the right flank, just inferior to rib 12
- Other hand used to palpate anteriorly in the RUQ
- As the patient breathes in, the kidneys descend (as the diaphragm moves down) and may become trapped between the palpating hands for examination
Which structures are in contact with the left and right superior pole of the kidneys?
Left: spleen
Right: liver
These structures are in contact with the diaphragm superiorly, and so move down with it during inspiration and move the kidneys down too as a result
Describe 5 features of a normal kidney on ‘balloting’
~12 cm long ~6 cm wide Smooth to touch Regular texture Firm to touch
What 4 visceral structures does the left kidney lie posterior to?
- Stomach
- Tail of pancreas
- Hilum of spleen
- Splenic vessels
What 4 visceral structures does the right kidney lie posterior to?
- Liver (+ hepatorenal recess)
- 2nd part of duodenum
- Ascending colon
- Right colic flexure
What is the hepatorenal recess and why is it important?
It is the most inferior + dependent part of the greater sac of the peritoneal cavity in the supine patient
This means that abnormal fluid in the peritoneal cavity will collect here when the patient lies down
Lymph from the kidneys drains to the lumbar/iliac nodes?
Lumbar
located around the abdominal aorta and IVC
Lymph from the ureters drains to the lumbar/iliac nodes?
Lumbar AND iliac nodes
The ureters get their blood supply from multiple sources as they have a long pathway. Arterial blood supply to the ureters comes from branches of which 5 arteries?
Renal artery Abdominal aorta Common iliac artery Internal iliac artery Vesical (bladder) artery
The renal arteries lie anterior/posterior to the renal veins?
Posterior
The common iliac arteries lie anterior/posterior to the common iliac veins?
Anterior
The abdominal aorta bifurcates at what level?
The level of the umbilicus (~T10)
List 5 anatomical variations of the kidney which may be seen
Bifid renal pelvis
Bifid ureter
Retrocaval ureter (passing inferior to IVC instead of laterally)
Horseshoe kidney (two kidneys joined in centre)
Ectopic pelvic kidney (kidney located down in pelvis)
How is the kidney structured similarly to the adrenal glands?
It has an outer renal capsule, a renal cortex, and an inner renal medulla
What is meant by the renal pyramids?
The renal medulla contains renal pyramids, each of which are formed by ~50,000 nephrons
What are nephrons?
The filtering unit of the kidneys
They are composed of a glomerulus (the filter) and a tubule
Why do the renal pyramids have a striated appearance?
The nephrons are regularly arranged towards the apex of each pyramid
Describe the route of urine draining from a nephron to the ureter out of the kidney
Nephron's collecting duct -> Minor calyx -> Major calyx -> Renal pelvis -> Pelviureteric junction -> Ureter
Define the…
Major calyx
Renal pelvis
Pelviureteric junction
Major calyx: where multiple minor calyces meet
Renal pelvis: where the major calyces converge at the core of the kidney
Pelviureteric junction: the first constriction site of the renal system, where the renal pelvis becomes the ureter
Describe the change in diameter of the structures draining urine from the kidneys to the ureter
Diameter increases until the pelviureteric junction, where the wide renal pelvis becomes the narrower ureter
What are the 3 anatomical sites of ureteric constriction?
Pelviureteric junction
Where the ureter crosses the anterior aspect of the common iliac arteries + the pelvic rim
Ureteric orifice (ureter opening into one corner of the trigone of the floor of the bladder)
What are the 3 anatomical sites of ureteric constriction?
Pelviureteric junction
Where the ureter crosses the anterior aspect of the common iliac arteries + the pelvic rim
Ureteric orifice (ureter opening into one corner of the trigone of the floor of the bladder)
What is the clinical significance of the 3 ureteric constriction sites?
Renal calculi (stones) can become lodged in them and obstruct the urinary tract
Calculi also often become stuck in the calyces
What is a ‘staghorn’ calculus?
A large renal stone which becomes stuck in the calyces and renal pelvis, forming the shape of a stag’s antlers
What are renal calculi/stones formed from?
Urine calcium salts
Can renal calculi/stones be seen on xray?
Yes, usually
This is done with x-ray and intravenous urogram
How does the ureter respond to either internal obstruction or external compression?
The smooth muscle within the walls of the ureter contracts (i.e., increases peristalsis) proximal to the obstruction to try to remove it
Why does a patient with ureteric obstruction complain of pain that comes and goes?
The increased peristalsis adopted to try to remove the obstruction comes in waves
The pain that comes and goes is described as ‘colicky’ pain
What is the consequence of urinary tract obstruction?
There is back pressure of urine up towards the kidneys
What can back pressure of urine cause?
Renal failure
This occurs when back pressure within the urinary tract exceeds pressures favouring filtration at the glomerulus
What is hydronephrosis?
Swelling of the kidneys due to urine back pressure
Why is acute hydronephrosis painful?
The renal capsule surrounding the kidney is a tough, tight, fibrous tissue and so tries to resist stretch
