Corticomedullary differentiation on T1-Weighted MRI: Comparison between cirrhotic and noncirrhotic patients

Purpose: To determine whether corticomedullary differentiation (CMD) is increased in patients with cirrhosis compared to controls on axial T1-weighted magnetic resonance imaging (MRI). Materials and Methods: Sixty patients with cirrhosis and 60 age-matched controls without renal disease underwent axial, T1-weighted in-phase gradient echo abdominal MRI. Each group of 60 was subdivided into three groups of 20 patients based on age: 18 to 45 years old; 45 to 65 years old; and greater than 65 years old. Signal intensity measurements of regions of interest obtained within the cortex and medulla of each kidney were recorded and the cortex-to-medulla contrast-to-noise ratio (CM-CNR) was calculated. Each patient's estimated glomerular filtration rate (eGFR) was recorded. Results: Mean CM-CNR for both kidneys in cirrhotic patients (19.1 ± 10.5) was significantly higher than in controls (12.4 ± 5.0) (P < 0.0001). No significant correlation was observed between CM-CNR and eGFR levels for both cirrhotics and controls (P > 0.05). When stratified by age groups, no difference was observed in the mean CM-CNR for both kidneys among these three subgroups for both cirrhotics and controls (P > 0.05). Conclusion: Cirrhotic patients with normal renal function have an increased CMD compared to age-matched controls.