Terminal zones of myelination
The terminal zones of myelination are located at the posterior aspect of the lateral ventricles (the peritrigonal regions) and are the only part of the cerebral white matter that may exhibit high T2 signal in a normal brain at 2 years of age, when myelination of cerebral white matter normally becomes complete.
Radiographic features
MRI
- T1 IR: low signal; better sensitivity than conventional T1 sequence
- T2: patches of high signal
Related pathology
Differentiation between these lesions and periventricular leukomalacia (PVL) is important as the terminal zone has no clinical relevance. Detection of normally myelinated low T2 signal white matter in-between the high signal patches and the lateral ventricle favors the diagnosis of terminal zone.