Deep Medullary Vein Involvement in Neonates with Brain Damage: An MR Imaging Study

BACKGROUND AND PURPOSE: Different and specific MR imaging patterns of lesions involving WM are widely defined in neonatal encephalopathy. The aim of this study was to describe a novel MR imaging pattern of damage characterized by the abnormal prominence of DMVs in premature and full-term neonates.

MATERIALS AND METHODS: Twenty-one (11 premature and 10 full-term) neonates with MR imaging evidence of linear radially oriented fan-shaped lesions in the periventricular WM and without dural venous thrombosis were enrolled in this retrospective study. A total of 37 MR imaging examinations were performed at ages ranging from day 0 to 24 months.

RESULTS: According to the appearance of linear anomalies on T2-weighted images, we identified 2 main patterns: T2 hypointense lesions without WM cavitations and T2 hypointense lesions associated with linear cysts. The first pattern was found in 17 examinations performed between 0 and 44 days of life; the second pattern was found in another 14 examinations performed between 6 days and 4 months of life. Five examinations performed between 9 and 24 months of life showed a reduction in volume and hyperintense signal intensity of the periventricular WM on T2-weighted and FLAIR images.

CONCLUSIONS: Subtle linear WM lesions with the same anatomic distribution of DMVs may be evident in premature and full-term neonates without signs of major venous thrombosis, both in the acute and subacute phases. Their appearance and evolution suggest that transient DMV engorgement/thrombosis may be responsible for WM damage that can lead to a PVL-like pattern.