Characteristics of the normative database for the Humphrey matrix perimeter.
OBJECTIVE
The Humphrey Matrix (Carl Zeiss Meditec, Dublin CA; Welch-Allyn, Skaneateles, NY) is a high-spatial-resolution perimeter that uses frequency-doubling stimuli. It incorporates an efficient test strategy that assumes that age, eccentricity, and test procedure type have only small effects on sensitivity. The results used to create the normative database for the perimeter were examined, to see whether these assumptions were met and to examine the form of the normative data.


METHODS
Visual fields were measured (Matrix 30-2, 24-2, 10-2 and Macula patterns) in >275 subjects judged to be normal by a battery of clinical procedures. The right eye was always tested first.


RESULTS
Sensitivity decreased by approximately 0.7 dB per age decade across all eccentricities; sensitivity decreased with eccentricity, typically by <5 dB at the most peripheral points tested. Although there was no systematic difference in sensitivity between the 30-2 and 24-2 tests, the Macula test sensitivities were typically 1 dB higher than for the 10-2 test. Sensitivity in the left eye was slightly lower than in the right, with the difference being significantly greater in the temporal visual field. In most test locations, the 95% confidence interval of normal sensitivity was approximately 6 dB below the median sensitivity.


CONCLUSIONS
The performance of the test strategy in the Matrix perimeter is appropriately matched to the response characteristics of the normal population. The finding of a spatially nonuniform difference in sensitivity between left and right eyes is attributable to light-adaptation differences between the eyes. This effect is accounted for in the perimeter's normative database.
Anderson
Andrew John
AJ
Discoveries in Sight, Devers Eye Institute, Portland, Oregon, USA.
Johnson
Chris A
CA
Fingeret
Murray
M
Keltner
John L
JL
Spry
Paul G D
PG
Wall
Michael
M
Werner
John S
JS
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002648:Child; D006801:Humans; D008875:Middle Aged; D012016:Reference Values; D012680:Sensitivity and Specificity; D058609:Visual Field Tests / Q000592:standards*; D014794:Visual Fields / Q000502:physiology*