Adv Exp Med Biol
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Since some important forms of brain injury in premature infants are caused in considerable part by disturbances in cerebral blood flow (CBF), it is important to be able to detect whether the cerebrovascular autoregulation, the mechanism by which CBF is maintained constant despite alterations in mean arterial blood pressure (MAP), is working properly. A recent study suggested that concordant changes in MAP and cerebral intravascular oxygenation (HbD), measured non-invasively by near-infrared spectroscopy (NIRS) as the difference between the concentration changes of oxygenated hemoglobin (HbO2) and deoxygenated hemoglobin (Hb), reflect impaired cerebrovascular autoregulation. ⋯ The concordance between MAP and HbD was quantitated using three different measures, among which a newly developed measure that looks for similarity of the dynamics between signals. Some preliminary results obtained from the measured data are given.