Enhanced regional cerebral metabolic interactions in thalamic circuitry predicts motor recovery in hemiparetic stroke.

We applied a multiple regression/discriminant analysis to resting metabolic data from patients with first hemiparetic suprathalamic infarctions to determine if metabolic interdependencies, which may separate recovered (N=12) from nonrecovered (N=9) patients, suggest important motor-recovery pathways. Recovered, vs. nonrecovered, patients showed an enhanced ipsilesional thalamic-contralesional cerebellar metabolic interdependency. This pattern correctly classified 91% of recovered and 88% of nonrecovered patients. Metabolic interactions involving bilateral supplementary motor area, ipsilesional thalamus, and contralesional cerebellum distinguished all recovered patients from age/sex-matched controls (N=12). These results suggest that altered functional interactions in thalamic circuitry may reflect plastic reorganization associated with motor recovery from hemiparesis.