Cerebral blood volume and oxygenation among poststroke hemiplegic patients: effects of 13 rehabilitation tasks measured by near-infrared spectroscopy.

OBJECTIVE: To measure with near-infrared spectroscopy (NIRS) the changes in cerebral hemodynamics and oxygenation in the prefrontal cortex of poststroke patients with hemiplegia performing several rehabilitation tasks and to analyze the different effects of the tasks.
DESIGN: Case series pilot study.
SETTING: Hospitals and facilities near Tsukuba, Japan. PARTICIPANTS: Twenty-four healthy volunteers and 44 patients with hemiplegia.
INTERVENTIONS: For healthy volunteers, conventional rehabilitation tasks of head-up tilt (HUT), calculation, and ergometer. For patients with hemiplegia, these 3 tasks plus reading aloud, listening to music, reciprocal extension, nonparalyzed extension, passive range of motion, pulley, bridge, facilitation, stand-up, and gait. MAIN OUTCOME MEASURES: Changes in cerebral blood volume (CBV) and cerebral oxygen volume (COV) in the prefrontal region sensed by a noninvasive NIRS device placed midforehead in healthy volunteers or on the impaired side in patients with hemiplegia. Computer analysis of the quality and quantity of the CBV and COV change patterns.
RESULTS: In healthy subjects, the change patterns of the 3 tasks were clearly different: decrease in COV with HUT, limited increase in CBV and COV with calculation tasks, and gradual increase in CBV and COV with ergometer tasks. In patients with hemiplegia, significant (positive) CBV changes were observed in ergometer, facilitation, stand-up, and gait and significant (negative) changes with Romover. Significant (positive) COV changes were observed in ergometer and facilitation and (negative) in HUT.
CONCLUSIONS: NIRS is useful for monitoring the change in regional hemodynamics and oxygenation in rehabilitation; some tasks commonly used in rehabilitation, such as ergometer and facilitation, increase both CBV and COV in the affected prefrontal cortex of patients with hemiplegia.