His research interests have always been related to cerebral blood flow and cerebral protection from ischemia. Based on some preliminary studies done in primates early in his career it was discovered that cerebral blood flow could be augmented by various manipulations of the cardiovascular system. This resulted in the adaptation of such techniques in the clinical realm especially as an effective means of counteracting the ischemic effects of cerebral vasospasm. This program ultimately evolved into what has come to be recognized as hyperdynamic therapy. Subsequently his clinical interests have related to various surgical approaches to intracranial vascular and cranial base neoplastic disease. Recently his attention has turned to looking at ethnic differences in the presentation of cerebral vascular disorders.