Transcranial Optical Monitoring of Cerebrovascular Hemodynamics in Acute Stroke Patients

Diffuse correlation spectroscopy (DCS) is a technology for non-invasive transcranial measurement of cerebral blood flow (CBF) that can be hybridized with near-infrared spectroscopy (NIRS). Taken together these methods hold potential for monitoring hemodynamics in stroke patients. We explore the utility of DCS and NIRS to measure effects of head-of-bed (HOB) positioning at 30 degrees, 15 degrees, 0 degrees, -5 degrees and 0 degrees angles in patients with acute ischemic stroke affecting frontal cortex and in controls. HOB positioning significantly altered CBF, oxy-hemoglobin (HbO(2)) and total-hemoglobin (THC) concentrations. Moreover, the presence of an ipsilateral infarct was a significant effect for all parameters. Results are consistent with the notion of impaired CBF autoregulation in the infarcted hemisphere. (C) 2009 Optical Society of America