Explain the physiology and morphology of the normal nephrographic pattern.
Description of the different alterations of the nephrographic pattern and its physiopathological correlation.
Show the differential diagnosis of the altered nephrographic patterns.
The nephrographic pattern is defined as the radiological image of the opacified renal parenchyma that is obtained after administration of intravenous contrast.
The pathophysiology of this pattern depends on the concentration of contrast in the plasma,
the glomerular filtration rate and the transit time of contrast through the kidney.
Fig. 1 Fig. 2
The glomerular filtration rate (GFR) depends on Fig. 3 :
Ultrafiltration coefficient (Ku).
Hydrostatic pressure in the intraglomerular capillary (Pi).
Oncotic pressure of the intraglomerular capillary (Po).
Hydrostatic pressure (Pc) in the...
Findings and procedure details
NORMAL CT NEPHROGRAM
Classic descriptions divide the appearance of the nephrogram into distinct phases (unenhanced,
nephrographic and excretory) that are based on the transit of contrast material through the kidney.
The different phases of the nephrogram must be symmetrical (beginning,
time of disappearance and enhancement)
In case of asymmetry,
the renal parenchyma that presents a delay of the nephrogram will be the pathological one
Unenhanced CT Fig. 4 :
It allows comparing and evaluating contrast uptake in subsequent phases.
Useful for differential diagnosis between...
The exhaustive analysis of the nephrogram is crucial in the evaluation of the pathology of the urinary tract.
Recognizing nephrographic abnormalities within the appropriate clinical setting allows the radiologist to suggest the correct diagnosis,
even before the clinical findings are evident.
The CT nephrogram: implications for evaluation of urinary tract disease.
RadioGraphics 1995; 15:1069–1085
Different phases of renal enhancement: role in detecting and characterizing renal masses during helical CT.
AJR 1999; 173:747–755
Computed tomography of renal agenesis and ectopy.
J Comput Tomogr 1984; 8:137–143.
Classic signs in uroradiology.
RadioGraphics 2004; 24(suppl 1):S247–S280.