Hydronephrosis is commonly divided into four grades according to dilation of the pelvicalyceal system and cortical thinning that can be visualised on ultrasound, CT and MRI.
Grade | Description |
---|---|
Grade I | dilation of the renal pelvis without dilatation of the calices |
Grade II | dilation of the renal pevis and calices, that become convex; no signs of cortical thinning |
Grade III | presence of cortical thinning |
Grade IV | massive dilation of the real pelvis and calices, severe cortical thinning |
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