A time-gated technique to reduce the effect of light scattering when transilluminating turbid media such as tissue is demonstrated. The concept is based on transillumination with picosecond laser pulses and time-resolved detection. By detecting only the photons with the shortest travelling time, and thus the least scattered photons, the contrast can be enhanced. Measurements on a tissue phantom as well as breast tissue in vitro are presented. It is demonstrated that the spatial resolution can be enhanced by using the time-gated technique. It is also shown that differences in scattering properties may be more pronounced than differences in absorption properties when demarcating tumor from normal tissue.

Date Published: 1 November 1991
PDF: 9 pages
Proc. SPIE 1525, Future Trends in Biomedical Applications of Lasers, (1 November 1991); doi: 10.1117/12.48209

Published in SPIE Proceedings Vol. 1525:
Future Trends in Biomedical Applications of Lasers
Lars Othar Svaasand, Editor(s)