Abstract：
:The precision of noninvasive optical measurement of the concentration changes in oxy-, deoxy-, and total-hemoglobin depends on wavelength. For estimating the precision, we calculated the noise level of the concentration changes as the uncertainty in measurements using several wavelength pairs of light. Seven laser diodes (664-848 nm) were used simultaneously for spectroscopic measurement of brain activity during finger motor stimulation. We also used the analysis of error propagation from the uncertainty in direct measurements of absorbance changes to estimate indirectly the uncertainty of concentration changes. The measurement of the concentration changes made using an 830/664-nm pair are two times (oxy-Hb) and six times (deoxy-Hb) more precise than those made using an 830/782-nm pair.
journal_name
Med Physjournal_title
Medical physicsauthors
Yamashita Y,Maki A,Koizumi Hdoi
10.1118/1.1373401subject
Has Abstractpub_date
2001-06-01 00:00:00pages
1108-14issue
6eissn
0094-2405issn
2473-4209journal_volume
28pub_type
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