Voxel-based map of the inter-arterial watershed zones in children

Purpose To create a voxel-based map of the inter-arterial watershed derived from children who have sustained a hypoxic-ischemic injury involving this region at term. Materials and methods Patients 0-18 years of age diagnosed with a hypoxic-ischemic injury of the watershed on magnetic resonance imaging (MRI) were included. Two pediatric neuroradiologists segmented the lesions as visualized on the T2-weighted sequence. All lesion maps were normalized to a brain template and overlapped to create a frequency map in order to highlight the frequency of involvement of portions of the cortical watershed. Results A total of 47 patients (35 boys) were included in the final sample. Their mean age was 7.6 +/- 3.6 years. The cortical watershed was successfully mapped. Three watershed regions were defined: the anterior, peri-Sylvian, and posterior watershed zones. The anterior and peri-Sylvian watershed zones are connected through the involvement of the middle frontal gyrus. The peri-Sylvian and the posterior watershed zones are connected through the involvement of the inferior parietal lobule, the posterior aspect of the superior temporal gyrus, and the angular gyrus with the occipital lobe. The temporal lobe and orbital part of the frontal lobe are largely spared in all patients. Conclusion A voxel-based lesion map of children with watershed hypoxic ischemic injury at term was created and three inter-arterial watershed zones defined: anterior, peri-Sylvian, and posterior watersheds.