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More MS news articles for February 2004

Orientational contrast sensitivity and chromatic contrast thresholds in multiple sclerosis

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14962418&dopt=Abstract

Am J Ophthalmol. 2004 Feb;137(2):283-6
Jackson TL, Ong GL, Ripley LG.
Sussex Eye Hospital, Brighton, United Kingdom

PURPOSE:

To investigate abnormalities of orientational contrast sensitivity (CS) and chromatic contrast threshold (CCT) in multiple sclerosis (MS).

DESIGN:

Case control study.

METHODS:

Nine subjects (mean age, 42 +/- 11 years; range, 20-62 years) with MS, an expanded disability status scale of 3 or less, and normal visual acuity (VA) (logarithm of the minimum angle of resolution [logMAR] VA less than.1) in the tested eye were age-matched with 20 controls.

Achromatic CS and CCT were measured using static, computer-generated sinusoidal gratings displayed on a high-resolution monitor.

The CS and CCT of each subject were determined using a randomized double-staircase reversal algorithm; CS was measured at five spatial frequencies with horizontal orientation and three with vertical orientation; CCT was measured along the red-green and tritan confusion axes.

The sensitivity thresholds of subjects were examined in relation to the mean sensitivity of controls for each spatial frequency.

RESULTS:

Two subjects had loss of horizontal and vertical CS, and three had isolated vertical loss.

When compared with the control mean, there were significant reductions in red-green (P =.016) and tritan (P =.016) discrimination thresholds.

CONCLUSION:

This study used a computerized psychophysical test designed to minimize many of the test errors associated with earlier studies.

It provides confirmatory evidence that MS may be associated with a loss of orientational CS and color vision, in the absence of reduced VA.