Fig. 6.

Correlation between age and morphological parameters. All of three morphological parameters, minimal cortical thickness, cortical area, and medullary area (upper) were negatively correlated with the age of the CKD patients. Predicted raw eGFR based on each morphological parameter using its peculiar regression line in Fig. 4 also significantly correlated with the age (lower). Predicted raw eGFR was calculated as follows: predicted raw eGFR by minimal cortical thickness (mL/min) = 10.06 × minimal cortical thickness (mm) + 0.728 (left); predicted raw eGFR by cortical area (mL/min) = 4.3 × cortical area (cm²) − 1.363 (middle); predicted raw eGFR by medullary area (mL/min) = 2.3 × medullary area (cm²) + 13.42 (right)