Abstract: Methods and systems are provided for a pulse oximetry probe configured to measure blood originating from the internal carotid artery. One example system includes a light emitter and a light detector coupled to a substrate and an attachment mechanism configured to couple the nasal pulse oximetry probe to a nose of a patient, the light emitter and light detector positioned on opposite sides of the nose at the root of the nasal bridge. One example method determines peripheral arterial oxygen saturation (SpO2) respiratory variability as well as other physiological parameters from measurements taken from the internal carotid artery.

Abstract: An apparatus, such as a photoplethysmographic sensor, including a light source configured to illuminate a target, wherein the apparatus is configured to receive incident light reflected from or transmitted through the target. The apparatus includes also a reflective element configured to direct at least part of the received incident light to a focus point, and a photodetector configured to receive light from the focus point.

Abstract: An apparatus with a photodetector area comprising a first photodetector area and a second photodetector area, the first and second photodetector areas having co-planar interlocking shapes, and an optical blocking filter configured to filter light incident on the second photodetector area.

Abstract: Methods and systems are provided for a nasal pulse oximetry probe configured to measure blood originating from the internal carotid artery. One example system includes a light emitter and a light detector coupled to a substrate and an attachment mechanism configured to couple the nasal pulse oximetry probe to a nose of a patient, the light emitter and light detector positioned on opposite sides of the nose at the root of the nasal bridge.