Renal tract anatomy (excl. kidneys) Flashcards
How long are the ureters?
25-30cm long
How wide are the ureters?
3-4mm in diameter
Where do the ureters lie?
In the retroperitoneal space
Where do the ureters arise from?
Pelvis of kidney
Where do the ureters exit the kidney?
Hilum in the transpyloric plane at L1
Where do the ureters pass in relation to the posts major?
Pass anteriorly to the posts major
Which part of the bladder do the ureters enter at?
Lateral aspect in an oblique fashion
Why do the ureters enter the bladder in an oblique direction?
Creates a valve that prevents back flow of urine
What are the 3 main points of constriction of the ureters?
Pelvicoureteric junction of renal pelvis and ureter (PUJ)
Bifurcation of the common iliac arteries
Vesicoureteric junction (VUJ)
Mass effects of what can cause ureteric obstruction?
Constipation
Pregnancy
Ovarian cysts
Nerves to the ureters arise from where?
Renal plexus
The renal plexus is supplied by nerves from where?
Thoracic splanchnic nerves
Sensory input from the ureters travels to what spinal levels?
T11-L2
Referred pain from the ureters can be felt where?
Posterior lumbar/ flank region
OR
hypogastrium
How much urine can the bladder hold?
300-600ml
At what volume does the bladder need to be at to cause the sensation of needing to void?
400ml
What is the bladder enveloped in?
Extraperitoneal fat + connective tissue
What is the bladder separated from the pubic symphysis by?
Anterior premedical space (space of retzius)
What are the 4 surfaces of the bladder?
Superior surface
Two inferolateral surfaces
Posterior surface
What are the 4 areas of the bladder?
Apex
Body
Fundus
Neck
What is the trigone of the bladder?
A smooth triangular region situated in the fundus of the bladder
What form the trigone?
2 ureteral orifices and urethral orifice
What is the name of the muscle in the wall of the bladder?
Detrusor
When does the detrusor muscle contract?
During micturition
Who is the internal urethral sphincter present in?
Males
Who is the external urethral sphincter present in?
Both sexes
What is the function of the internal urethral sphincter?
Prevents se final regurgitation during ejaculation
What type of control is the internal urethral sphincter under?
Autonomic
What type of control is the external urethral sphincter under?
Voluntary
What does the external urethral sphincter do during micturition?
Relaxes
What is the arterial supply to the bladder?
Superior vesical bronco of the internal iliac artery
**also the inferior vesical artery in men/ vaginla artery in women
What is the venous drainage of the bladder?
Vesical venous plexus
The superior aspect of the bladder drains to which nodes?
External iliac nodes
The posteroinferior aspect of the bladder drains to which nodes?
Internal iliac drugs
Some vessels from the neck of the bladder drain to which nodes?
Sacral/ common iliac nodes
What is the sympathetic innervation of the bladder?
Hypogastric nerve (T12-L2)
What does sympathetic stimulation of the bladder cause?
Relaxation of detrusor = retention of urine
What is the parasympathetic innervation of the bladder?
Pelvic splanchnic berves
Parasympathetic stimulation of the bladder causes what?
Contraction of detrusor = micturition
What is the somatic innervation of the bladder?
Pudendal nevre (S2-S4)
What does somatic innervation of the bladder act on?
External urethral sphincter
Somatic control over the bladder causes what?
Voluntary control of the external urethral sphincter = relaxation/ constriction
What do sensory afferents of the bladder detect?
Sense when the bladder is stretched and full
Spinal cord transection above T12 causes what to happen to the bladder?
Spastic (reflex) bladder
What happens in a spastic bladder?
The bladder automatically empties as it fills as the parasympathetic efferents are intact, but the other nerves are not.
Spinal cord transection below T12 causes what to happen to the bladder?
Flaccid bladder
What happens in a spastic bladder?
Urinary retention (can sometimes lead to reflux nephropathy)
How long is the male urethra?
15-20cm long
What are the 3 points of constriction in the male urethra?
Internal urethral sphincter
External urethral sphincter
External urethral orifice
What are the 4 parts of the urehtra?
Pre-prostatic
Prostatic
Membranous
Spongy
What is the widest and most dilatable part of the male urethra?
Prostatic part
What is the narrowest part of the male urethra?
Membranous
Where is the membranous part of the male urethra located in?
Deep perineal pouch
The spongy part of the urethra passes through what?
Penis
Which part of the male urethra are Cowper’s glands located in?
Spongy part
How long is the female urethra?
4cm
What is the arterial supply to the prostatic urethra?
Inferior vesical artery
What is the arterial supply to the membranous urethra?
What is the arterial supply to the female urethra?
Pudendal, vaginal and inferior vesical branches of the vaginal arteries
What is the lymphatic drainage of the urethra?
Internal iliac nodes
Deep inguinal nodes
What is the innervation of the male urethra?
Pudendal nerve
Prostatic plexus (arises from inferior hypogastric plexus)