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Proceedings Paper

Quasi-Elastic Light Scattering And Other Objective Measures Of Cataractous Change In Vivo
Author(s): Leo T. Chylack,Jr.; David Magnante
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Paper Abstract

Quasielastic light scattering technology provides a means of obtaining a linear measure of the total light scattered by the lens or cornea. This technology has been applied to a population of normal volunteers and a group of patients with different types of cataracts. The replicate errors have been measured for 5 and 50 microsecond sample times in both the cortex and the nucleus of the human crystalline lens in vivo, and they vary from 10-13%. The regional error associated with a change in the location of the pickup, a variation over an area of 225 square microns, is 18-20%. The change from a clear to a cataractous cortex is associated with wide fluctuations in total light scattered; in our population, the mean decreased slightly. In the nucleus, the total light scattered by opaque nuclei was 400% greater than that scattered from non-cataractous, age-matched control nuclei. It appears as if the signal-to-noise ratio for this instrument applied to humans is likely to be 10-20/1. This should enable one to detect small changes in the light scattering properties of the lens in vivo and should make clinical trials of anticataract drugs tolerably short in duration and affordable. Other film-based technologies for in vivo objective measurement of cataractous change along with their strengths and weaknesses are also discussed. Specifically the Topcon SL-45, the Topcon SL-5D/6E, the Neitz CTR and the Zeiss-Kawara cameras are discussed.

Paper Details

Date Published: 10 March 1987
PDF: 5 pages
Proc. SPIE 0712, Lasers in Medicine, (10 March 1987); doi: 10.1117/12.937338
Show Author Affiliations
Leo T. Chylack,Jr., Brigham and Women's Hospital and Harvard Medical School and Tufts University School of Medicine (United States)
David Magnante, Brigham and Women's Hospital and Harvard Medical School and Tufts University School of Medicine (United States)


Published in SPIE Proceedings Vol. 0712:
Lasers in Medicine
Stephen N. Joffe; John A. Parrish, Editor(s)

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