The Influence of Simulated Light Scattering on Automated Perimetric Threshold Measurements

Dale K. Heuer, Douglas R. Anderson, Robert W. Knighton, William J. Feuer, Michael G. Gressel

Research output: Contribution to journalArticlepeer-review

37 Scopus citations

Abstract

The effect of light scattering by ocular media opacities on OCTOPUS and Humphrey perimeter threshold measurements was simulated with randomly ordered sequences of six ground-glass diffusers in the right eyes of five subjects. Threshold measurements were performed at 0°, 5°, 10°, 15°, 20°, and 25° nasally along the 180° meridian with the F4 program on an OCTOPUS perimeter, and with twice-repeated profiles on a Humphrey perimeter. The reduction in differential light sensitivity correlated well with the 2.7-dB to 16.7-dB reduction in stimulus intensity caused by the 46% to 98% scattering of incident light by the diffusers. Contrast sensitivity in the presence of a glare source (Miller-Nadler glare test) was also affected by the diffusers, such that a 75% contrast target was not visible through the strongest diffuser whereas a 5% contrast target was visible without a diffuser. Conversely, the diffusers had very little effect on visual acuity measurements that were performed with projected high-contrast targets in a darkened room. Our data suggest that even minimal light scattering, such as might be caused by a cataract that has a relatively insignificant effect on visual acuity, may influence threshold measurements.

Original languageEnglish (US)
Pages (from-to)1247-1251
Number of pages5
JournalArchives of ophthalmology
Volume106
Issue number9
DOIs
StatePublished - Sep 1988

ASJC Scopus subject areas

  • Ophthalmology

Fingerprint

Dive into the research topics of 'The Influence of Simulated Light Scattering on Automated Perimetric Threshold Measurements'. Together they form a unique fingerprint.

Cite this