Changes in cerebral blood flow (CBF) were measured and compared in 40 patients with putaminal hemorrhage who underwent either stereotactic hematoma aspiration or conservative treatment. There were no statistically significant differences in mean CBF or hemispheric CBF between the two treatment groups. Although there are claims of the superiority of surgery from the standpoint of integrated cortical function following mild putaminal hemorrhage, the results of this investigation indicate that conservative therapy is adequate in such cases, based on improvement in CBF.