EARLY DETECTION OF ACUTE TUBULAR INJURY WITH DIFFUSION-WEIGHTED MAGNETIC-RESONANCE-IMAGING IN A RAT MODEL OF MYOHEMOGLOBINURIC ACUTE-RENAL-FAILURE

We evaluated the feasibility of magnetic resonance imaging (MRI) for e arly detection of tubular injury by monitoring changes in the apparent diffusion coefficient (ADC) of renal Linter in a rat model of myohemo globinuric glycerol-induced acute renal failure (ARF), Diffusion-weigh ted MRI was performed concurrently with measurements of serum creatini ne and blood urea nitrogen (BUN), evaluation of renal perfusion with d ynamic contrast-enhanced MRI, and renal morphological examination. ADC values in the cortex and outer medulla significantly declined within minutes after the glycerol administration (70-75% of control at 4 min and 50-60% of control at 15 min). Contrast-enhanced MRI demonstrated r enal hypoperfusion at 20 min after the onset of injury Light microscop y showed normal glomeruli and edematous tubular epithelial cells at 10 and 30 min, with more severe swelling and protein casts at 30 min, No changes in serum creatinine or BUN levels were detected. We hypothesi ze that decrease in renal ADC may be attributed to renal ischemia and to subsequent intracellular accumulation of diffusion-restricted water Similar imaging evaluation in other experimental models of ARE and in patients, will define the diagnostic value of renal ADC changes in ea rly detection of acute tubular injury.