Measurement of hemodynamics during postural changes using a new wearable cephalic laser blood flowmeter.

Background: Patients with orthostatic hypotension have pathologic hemodynamics related to changes in body posture. A new cephalic laser blood flowmeter that can be worn on the tragus to investigate the hemodynamics upon rising from a sitting or squatting posture was developed.

Methods And Results: The relationship between cephalic hemodynamics and cerebral ischemic symptoms in 63 subjects in a sitting, squatting, and standing positions using the new device was evaluated.

Fourier transform near-infrared spectrometer using a corner-cube integrated prism scanning interferometer.

This paper describes a Fourier transform (FT) near-infrared spectrometer that uses an integrated prism scanning interferometer whose optical paths are stabilized by corner cubes. A combination of corner cubes and a retroreflection mirror, which is sometimes used in the conventional interferometer for FT spectrometers, is adopted and adapted to the integrated prism scanning interferometer through a special design. Without any degradation of spectroscopic properties, the optical path in the interferometer is highly stabilized and the moving distance of the stage is halved.