Patent ID: 7047054
Filing Date: 2006-05-16
Classification: A61B

Abstract:
1. A near infrared spectrophotometric (NIRS) monitoring assembly for noninvasive monitoring of blood oxygenation levels in a subject's body, said assembly comprising: a) at least one flexible housing having a window and which can be attached directly to a subject's body; b) a plurality of laser light sources which are operatively associated with said housing, each of said light sources being operative to emit a near infrared light signal of a different wavelength, which light signals are transmitted through said housing window; c) a photodiode assembly which can be attached directly to the subject's body and which is operably connected to said light sources, said photodiode assembly being operative to measure light intensity values emanating from light emitted by said light sources and passing through the subject's body; and d) a laser safety interlock system designed to disable laser operation in case of assembly dislodgment from the patient's body, said safety interlock comprising: I) means for monitoring ambient light and emitted laser light; and II) means for processing signals received by said photodiode assembly so as to determine secure assembly attachment to the subject's body: i) by monitoring ambient light conditions and disabling laser operation when ambient light levels are greater than a predetermined level; ii) by monitoring laser output and disabling laser operation when laser output is outside of a predetermined range; and iii) by monitoring changes in detected laser output over a predetermined measuring period and disabling laser operation if changes in laser output are above or below predetermined levels during a predetermined measuring period.