Structural and Functional Imaging of Motor Outcomes in Twins With Perinatal Stroke: A Case Report

Perinatal arterial ischemic stroke (AIS) affects 1 in 4000 live births. Dystonia, affecting ~20% of children following AIS, is characterized by involuntary muscle contractions and abnormal movements. Why some develop dystonia post AIS, while others do not, remains unclear. We hypothesized that dystonia after AIS is associated with two key features: lesions involving frontal-basal ganglia network regions and corresponding disruptions in motor oscillatory activity.

Monozygotic twin brothers aged 11 years were recruited to a study investigating neural correlates of motor control in post-stroke dystonia. Brain magnetic resonance imaging (MRI) assessed lesion localization, volume, and white matter structure. Magnetoencephalography measured timing and localization of neural oscillations during movement execution and inhibition on the "go"/"no-go" task. Clinical history was obtained from charts. Neurological outcome was evaluated with the Pediatric Stroke Outcome Measure (PSOM).

MRI showed mirrored hemispheric lesions in the twins, with additional basal ganglia involvement in Twin A. Diffusion tensor imaging revealed lower corticospinal tract integrity in Twin A. MEG in Twin A revealed increased frontal theta (4-8 Hz) during correct inhibition. Sensorimotor gamma was reduced for Twin A but upregulated for Twin B during contralesional hand movement. Clinically, Twin A had a PSOM score of 2 (moderate motor and cognitive deficits); Twin B scored 0 (no deficits).

Our findings suggest that dystonia following perinatal AIS is associated with altered frontal-basal ganglia network function, with increased frontal recruitment reflecting compensatory disinhibition during motor control.