Motor Network Activation and Connectivity Patterns are Related to Outcomes Following Perinatal and Childhood Arterial...

Motor outcomes following perinatal and childhood stroke are highly variable and likely reflect complex structural and functional changes within motor-related brain networks. Greater understanding of these network mechanisms is needed to improve patient-specific prognostication and develop targeted therapies to restore motor function. This study explored poststroke motor-related reorganization patterns through assessment of functional magnetic resonance imaging (fMRI) activation and white matter (WM) connectivity.

Twelve children (age 9-19 years) with a history of perinatal or childhood stroke underwent 3T MRI with diffusion-weighted imaging and task-related hand-motor fMRI. The Pediatric Stroke Outcome Measure was used to assess motor outcome and dichotomize into two groups. MRI data were processed and analyzed for whole-brain fMRI activation patterns and WM track-weighted functional connectivity (TW-FC) profiles, in relation to motor outcomes.

Divergent fMRI activation and TW-FC patterns were seen between the two groups. Children in the no hemiparesis group were more likely to retain an ipsilesional fMRI activation pattern while children in the hemiparesis group were more likely to demonstrate bilateral or contralesional patterns. Increased utilization of cortical-subcortical pathways was identified by TW-FC in both groups. Greater TW-FC strength when moving the stroke-affected hand was also seen in the no hemiparesis group compared to the hemiparesis group.

We identified distinct patterns of motor network activation and WM connectivity relating to clinical outcomes after perinatal and childhood stroke. These patterns have potential to improve prognostic ability and aid identification of children who would most benefit from targeted therapy to improve long-term motor outcomes.