Share Email Print

Proceedings Paper

Optical fiber arrangement of optical topography for spatial resolution improvement
Author(s): Tsuyoshi Yamamoto; Eiji Okada; Fumio Kawaguchi; Atsushi Maki; Yukio Yamada; Hideaki Koizumi
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

In medical instrumentation, optical topography (OT) refers to the use of near-infrared spectroscopy for measuring brain function in systems. Arrays of optical fibers are attached to the scalps of subjects; infrared light is passed through the fibers, and changes in the reflections depict blood-volume changes in the cortex. In this study, the spatial resolution and locational accuracy of topographical images obtained by three arrangements of optical fibers was analyzed through simulation. Three arrangements, a "lattice arrangement" (LA), "double-density arrangement" (DA), and "quadruple density arrangement" (QA) were investigated. The density of spatial-sapling points is higher in the DA and QA than in the LA, i.e. the distance between sampling points for these arrangements were 21, 15 and 11 mm, respectively. The efficacy of these arrangements was evaluated. An adult head-structure phantom was prepared. The absorption coefficient in the phantom was varied to simulate brain activation in the cortex, and the resulting absorbance change (ΔOD) was thus obtained. The 'activated' area in the overall measurement area was fixed and the ΔOD at each of the sampling point in each arrangement was obtained. The resulting distributions of ΔOD were spatially interpolated to obtain topographical images. The spatial resolution and locational accuracy was obtained for each of the images; the results indicated that the DA is the most efficacious of the three arrangements. An experimental DA-OT system was then built. Topographical images of motor-function activation obtained by this system and a commercial LA-based system were compared; the DA-OT system provided the higher spatial resolution.

Paper Details

Date Published: 29 July 2003
PDF: 10 pages
Proc. SPIE 4955, Optical Tomography and Spectroscopy of Tissue V, (29 July 2003); doi: 10.1117/12.478126
Show Author Affiliations
Tsuyoshi Yamamoto, Hitachi, Ltd. (Japan)
Eiji Okada, Keio Univ. (Japan)
Fumio Kawaguchi, Hitachi Medical Corp. (Japan)
Atsushi Maki, Hitachi, Ltd. (Japan)
Yukio Yamada, Univ. of Electro-Communications (Japan)
Hideaki Koizumi, Hitachi, Ltd. (Japan)

Published in SPIE Proceedings Vol. 4955:
Optical Tomography and Spectroscopy of Tissue V
Britton Chance; Robert R. Alfano; Bruce J. Tromberg; Mamoru Tamura; Eva M. Sevick-Muraca, Editor(s)

© SPIE. Terms of Use
Back to Top