Grading System for Antenatally Detected Hydronephrosis
| Grade* | Central renal complex (pelvis) | Renal parenchymal thickness |
|---|---|---|
| 0 | Intact | Normal |
| I | Mild splitting = dilatation | Normal |
| II | Moderate splitting, but complex, confined to renal border | Normal |
| III | Marked splitting, pelvis dilated outside renal border, and calices dilated | Normal |
| IV | Further caliceal dilatation | Thin |
↵* Proposed by the Society of Fetal Urology (20).