Near-Infrared Spectroscopy and Imaging for Investigating Stroke Rehabilitation: Test-Retest Reliability and Review of the Literature
Abstract
Strangman G, Goldstein R, Rauch SL, Stein J. Near-infrared spectroscopy and imaging for investigating stroke rehabilitation: test-retest reliability and review of the literature.
Objectives
To review the use of near-infrared spectroscopy (NIRS) in stroke rehabilitation and to evaluate NIRS test-retest reliability within-session on a motor control task commonly used in neuroimaging of stroke recovery.
Design
Cohort study.
Setting
Hospital-based research laboratory.
Participants
Nineteen healthy control subjects (age range, 22−55y).
Interventions
Subjects performed 2 experimental runs of a finger-opposition task in a block-design paradigm (finger opposition alternated with a fixation rest period) while undergoing multichannel NIRS and physiologic monitoring.
Main Outcome Measure
Reliability coefficients (Pearson r) for oxyhemoglobin (O2Hb) and deoxyhemoglobin (HHb) correlated amplitude modulations across measurement channels during individual blocks and block averages.
Results
Correlations between single blocks (ie, 16-s slices of data) exhibited a correlation intercept of .33±.09 for O2Hb. This value was minimally decreased by increasing lag between compared blocks (slope, −.012; P=.019) but was substantially enhanced by averaging across blocks (within-run slope, .11; between-run slope, .044). Correlations using 64 seconds of data reached 0.6. Results for HHb were virtually identical.
Conclusions
NIRS modulations were repeatable even when comparing very short segments of data. When averaging longer data segments, the test-retest correspondences compared favorably to neuroimaging using other modalities. This suggests that NIRS is a reliable tool for longitudinal stroke rehabilitation and recovery studies.
aDivision of Psychiatric Neuroscience, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA
bDivision of Behavioral and Mental Health, Spaulding Rehabilitation Hospital, Harvard Medical School, Boston, MA
cDepartment of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Harvard Medical School, Boston, MA
Reprint requests to Gary Strangman, Neural Systems Group, Massachusetts General Hospital, 149 13th St, Psychiatry, Rm 2651, Charlestown, MA 02129
Supported by the National Institute of Neurological Disorders and Stroke, National Institutes of Health (grant no. K25-NS046554).
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.
ABSTRACT