renal imaging Flashcards
decr in intensity of x-ray beam caused by absorption of photons in tissue
attentuation
the change in density of a tissue following admin of IV contrast
enhancement
hounsfield unit of -1000
air
hounsfield unit of -120
fat
hounsfield unit of 0
water
hounsfield unit of +40
muscle
hounsfield unit of +400
bone/Ca
lack of echoes b/c a structure lacks internal acoustic reflectors (ie cysts are black)
anechoic or sonolucent
when an ultrasound beam passed thru fluid, the intensity of the sound nrg is not diminished
enhanced thru transmission
1st line of imaging test in patients with unexplained hematuria or renal dysfxn
U/S
what is the major method of imaging in characterizing cystic and solid renal lesions?
CT
the portion of the cortex that forms the base of the lobe is____
centrilobular
the portion of the cortex that surrounsd the sides of the medulla is called the ______
septal cortex
most kidneys are position b/w the ______lumbar vertebrate
1st & 3rd
phrase for the perinephric space bounded by the anterior and psoterior renal fascia
gerotas fascia
what radiographic imaging is most sensitive for evaluating flank pain
CT
most common cause of flank pain
renal stone disease
gold standard for imaging of flank pain
non contrast enhanced helical CT
msot direct sign of ureteral calculus?
visualization of the calculus of the ureter
most common renal mass seen on U/S
simple cyst
incidental adreanl mass discovered on an imaging study obtained for other reasons
incidentaloma
most adrenal incidentalomas are benign or malignant
benign
recommedned f/u for adrenal incidentaloma 3-5 cm
surgery vs f/u vs other imaging
what are the high risk malignancies for adrenal incidentaloma?
breast, lung, melanoma
excessive excretion & precipitationg of salts in urine or a lack of inhibiting substances
urolithiasis
urolithiasis is more common in
men, older, non-Af Am
rim of tissue around a stone at the impaction site; urethral wall edema
soft tissue rim sign
what secondary sign has a high positive perdictive value in patient with acute flank pain
hydroureter and perinephric stranding
most cost effective method of defining and confirming benign cyst
U/S
CT with HU under 20, no wall enhancement,no calcification of nodularity
simple cyst
what makes a cyst not simple (7)
- calcification
- hyperattentuation >20 HF units
- septations
- multiloculated
- nodularity
- thick wall
- enhancement
U/S with anechoice, no perceptible wall, enhanced thru transmission
simple cyst
what class: simple benign cyst with thin walls, no septa or calcifications
bosniak category 1 cystic mass
what class: benign cystic lesions that may contain thin septa with fine linear calcification in walls
bosniak category 2 cystic mass
what class: more complex cysts w/ incr #septa, incr calcifcication, thicker, more nodular
bosniak category 2F cystic mass
what class: indeterminate masses thick irregular walls or septa with large amt of calcifications
bosniak category 3 cystic mass
what class: malignant cystic masses with thick irregular enhancing walls or septa containing small of large amts of Ca
bosniak category 4 cystic mass
f/u for bosniak class 1
no imaging f/u
fu of bosniak category 2
if larger than 3 cm then f/u
most common solid renal mass
renal cell carcinoma
____tend to be tumefactive & ____are infiltrative
RCC; transitional cancers
if you see a solid round mass, what is it until proven otherwise?
renal cell carcinoma
which carcinomas have epicenters in renal sinus (2)
- transitional cell carcioma
2. squamous cell carcinoma
which carcinomas have epicenters in parenchyma (3)
- lymphoma
- infiltrating RCC
- metastases
adrenal mass >6 cm is most likely?
malignant
best test for determining whether incidental adrenal mass is adenoma is?
CT with pre & post contrast delayed imaging
