Genitourinary CT Flashcards
What are the stages of a normal CT nephrogram?
Cortical arteriogram
Cortical nephrogram
Tubular/Generalized nephrogram
What part of the kidney has contrast reached in the cortical angiogram?
Interlobar arteries and glomeruli of the kidneys
Where is the contrast on the cortical nephrogram phase?
Cortical capillaries
Peritubular spaces
Filters into cortical tubular lumina
What components are opacified with contrast in the tubular/generalized nephrogram?
Loop of Henle
Collecting tubules
What is the differential for global absence of nephrogram?
Complete renal ischemia secondary to interruption of primary renal perfusion is occlusion of main renal artery.
Causes include -
Trauma of vascular pedicle
Thromboembolic disease
Renal artery dissection
What is the differential for segmental defects of nephrogram?
Masses - neoplasm, cysts, abscess ie displace renal parencyma
Peripheral arterial obstruction - Arterial emboli arterial thromboses vasculitis septic shock renal vein thormbosis Emboli
What is the rim nephrogram or rim pattern of undwrperfusion?
Thin peripheral band of cortical opacification. Due to sub capsular flow from collateral vessels such as retroperitoneal, lumbar, iliac, intercostal, adrenal, phrenic.
What is the differential for a rim nephrogram?
Specific sign for renovascular compromise.
Renal vein thrombosis
Acute tubular necrosis
What is a delayed nephrogram?
Temporal delay of one kidney of contrast
What is the differential for a delayed nephrogram?
Renal artery stenosis
Renal vein thrombosis
Obstructive uropathy
What is a striated nephrogram?
Alternating bands of high and low attenuation parallel to axis of tubules and collecting ducts.
What is the differential of unilateral striated nephrogram?
Ureteric obstruction
Acute pyelonephritis
Contusion
Renal vein thrombosis
What is the differential for bilateral striated nephrogram?
Acute pyelonephritis
Tubular obstruction
Hypotension
Autosomal recessive polycystic kidney disease
Intratubular obstruction (Tamm-horsfal, rhabdomyolysis)
