Criteria for magnetic resonance imaging (MRI) and ultrasonography (US) diagnosis of white matter lesions
| Cerebral lesion | MRI | US |
|---|---|---|
| Cystic PVL | T1 weighted: extensive white matter lesion of signal intensity similar to that of cerebrospinal fluid and | Hyperechoic area (similar to the skull) with one or more echo-free areas (similar to cerebrospinal fluid) in the periventricular parenchyma. |
| T2 weighted: high signal in the same area, similar to the signal intensity of cerebrospinal fluid. | ||
| Non-cystic PVL | T1 weighted: high signal intensity in the white matter similar to the intensity of the skull and | One or more hyperechoic areas in the periventricular parenchyma. |
| T2 weighted: abnormal signal in the same area (high or low according to whether haemorrhage is present). | ||
| Parenchymal punctate haemorrhage | T1 weighted: small circular high signal in the parenchyma and | Small circular hyperechoic areas in the cerebral parenchyma |
| T2 weighted: low signal in the same area | ||
| Parenchymal haemorrhagic infarction | T1 weighted: unilateral, large triangular area of high signal and | Unilateral, large triangular hyperechoic area involving the lateral ventricle and adjacent parenchyma. |
| T2 weighted: low signal from the lateral ventricle and adjacent parenchyma. |