Optoacoustic infrared spectroscopy of soft tissue

Citation
Kp. Kostli et al., Optoacoustic infrared spectroscopy of soft tissue, J APPL PHYS, 88(3), 2000, pp. 1632-1637
Citations number
21
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF APPLIED PHYSICS
ISSN journal
00218979 → ACNP
Volume
88
Issue
3
Year of publication
2000
Pages
1632 - 1637
Database
ISI
SICI code
0021-8979(20000801)88:3<1632:OISOST>2.0.ZU;2-P
Abstract
Optical properties of soft tissue in the near infrared are determined using optoacoustic spectroscopy. The acoustic signals are generated with an opti cal parametric oscillator (OPO) having a tuning range from 1500 to 3500 nm. In order to record the acoustic wave on the same side as the exciting lase r pulse (backward mode), an infrared transparent pressure transducer was de veloped. The effective attenuation coefficients of cartilage and chicken br east were determined in a range between 1860 and 1940 nm. The minimum absor ption or effective attenuation coefficient that could be measured with the presented method was 10 cm(-1), limited by the detector sensitivity of 1.68 % signal change per bar. The maximum measurable coefficient was about 1000 cm(-1), limited by temporal broadening of the acoustic signals due to the f inite pulse duration (6 ns) of the OPO. Optoacoustic infrared spectroscopy is shown to be suitable for on-line noninvasive, in vivo tissue characteriz ation. (C) 2000 American Institute of Physics. [S0021-8979(00)06115-6].