Work

Quantitation of time- and frequency-resolved optical spectra for the determination of tissue oxygenation

Year: 1991

Type: article

Abstract: The recent development of near-infrared time- and frequency-resolved tissue spectroscopy techniques to probe tissue oxygenation and tissue oxygenation kinetics has led to the need for further quantitation of spectroscopic signals. In this paper, we briefly review the theory of light transport in strongly scattering media as monitored in the time and frequency domains, and use this theory to develop algorithms for quantitation of hemoglobin saturation from the photon decay rate (delta log R/delta t) obtained using time-resolved spectroscopy, and from the phase-shift (theta) obtained from frequency-resolved, phase-modulated spectroscopy. To test the relationship of these optical parameters, we studied the behavior of delta log R/delta t and theta as a function of oxygenation in model systems which mimicked the optical properties of tissue. Our results show that deoxygenation at varying hemoglobin concentrations can be monitored with the change in the photon decay kinetics, delta delta log R/delta t in the time-resolved measurements, and with the change in phase-shift, delta theta, in the frequency-resolved technique. Optical spectra of the adult human brain obtained with these two techniques show similar characteristics identified from the model systems.

Source: Analytical Biochemistry

DOI: 10.1016/0003-2697(91)90339-u

Authors: E.M. Sevick, B. Chance, J. Leigh, S. Nioka, M. Maris

Institution: University of Pennsylvania

Language: English

Topic: Optical Imaging and Spectroscopy Techniques

Subfield: Radiology, Nuclear Medicine and Imaging

Field: Medicine

Domain: Health Sciences

Open Access status: hybrid

Estimated APC paid: $3,540

Funders: National Heart, Lung, and Blood Institute, National Cancer Institute, National Institute of Neurological Disorders and Stroke