Diaschisis in right putaminal hemorrhage: correlation with motor function

Local cerebral lesions may cause depression of function in remote areas of the brain presumably by a transneural mechanism; it has been called "diaschisis". In the present study, to investigate the relationship between motor function and "diaschisis" regional brain blood flow in hypertensive right putaminal hemorrhage was studied in 33 patients (mean age, 55 years; 22 men, 11 women). The hematoma was treated conservatively in 8 patients, aspirated stereotaxically in 9 patients, and evacuated through a craniotomy in 16 patients. The regional blood flow in the right motor cortex and the left cerebellar hemisphere was measured by a single photon emission CT with N-isopropyl-p- (123 I) iodo-amphetamine intravenous injection method, and was evaluated by the RI count on early image/the decay-corrected RI count on delayed image (E/D) value. The time during which regional brain blood flow was measured ranged from 29 to 35 days from the onset. There was a positive correlation between the grade in the motor function in the subacute stage and the regional blood flow in the right motor cortex and the left cerebellar hemisphere. There was also a positive correlation between the Barthel index in the chronic stage (mean follow-up periods: 40 months) and the regional blood flow in the right motor cortex and the left cerebellar hemisphere. The results of the present study suggest that in right putaminal hemorrhage the flow reduction in areas remote from the primary lesion, i.e., "diaschisis", may reflect not only the degree of functional abnormalities of the internal capsule, but also the possibility of functional recovery.