imaging the urinary tract Flashcards
what can a raised creatnine indicate about the kidney
kidney injury -> look for old bloods and check for changes
what is the underlying cause of intrinsic, post-renal AKI
blockage e.g. stone, tumour
what is the underlying cause of extrinsic, post-renal AKI
pressure from external structures e.g. pelvic masses
what is the underlying cause of renal AKI
glomerulonephirits
what is the first line radiological investigation for AKI
ultrasound
how does fat appear on ultrasound
bright
how does a normal kidney appear on US
semicircular(ish) area of dark with a lighter central section (in the shape of the kidney parenchyma and renal pelvis
how do fluids appear on US
black -> if the renal pelvis is black it indicates that it is filled w urine -> blockage
how might a CKD kidney appear on US
- smaller
- thin cortex
- increased renal sinus fat
what is urolithiasis
calculi (stones) or the renal/urinary tract and bladder
best imagine modality for urolithiasis
CT
what is fat stranding
abnormal increased attenuation in fat on CT
what renal conditions is fat stranding seen on CT (2)
- acute pyelonephritis
- ureteric calculi
what does a widened ureter indicate on CT
obstruction
what is twinkling artifact on US
seen on colour flow doppler ultrasound - a focus of alternating colours on Doppler signal behind a reflective object (such as a calculus or air), which gives the appearance of turbulent blood flow
what is a ureteric jet
on colour doppler US urine can be seen jetting out of the ureter into the bladder -> if this occurs at a certain velocity then it indicated NO obstruction
generally used in pts who cant hv a CT -> pregnant/ young pts
causes of nephrocalcinosis (3)
- hyperparathyroidism
- renal tubular acidosis
- medullary sponge
what is renal tubular acidosis
damage to the kindeys meaning that acid-base balance cannot be kept in balance as waste is not being removed
what is US used for in renal cystic disease
diagnosis
what is CT/MRI used for in renal cystic disease
check up/monitoring -> CT used far more
what are poly cystic kidneys
a genetic disorder that causes many fluid-filled cysts to grow in your kidneys
how do cycts appear on imaging
- fluid filled
- homogenous
- thin wall
what imaging can be used for renal vascular disorders
MR angiogram
what is a con of MR renal angiography
very invasive proceedure
what is digital subtraction angiography
a fluoroscopy technique used in interventional radiology to clearly visualize blood vessels in a bony or dense soft tissue environment
how do renal infarcts appear on CT
- wedge shaped lesions
- non-homogenous kidney
- cortical rim sign
what is pyelonephritis
UTI that spreads to the kidneys
what is pyelonephritis easy to confuse with on CT
renal infarct -> Hx is key in determining diaagnosis
renal abscess features on CT (3)
- well defined mass
- thick wall
- fat stranding
