|Title||AGE NORMS AND STATISTICAL INDICES FOR FREQUENCY DOUBLING PERIMETRY|
|Author, Co-Author||Craig Adams, Chris Johnson, Mark Bullimore, Kimberly Cello, Jacqueline Nelson-Quigg, William Choi, Samuel Fallejo|
Southern Hem IV
|Abstract|| PURPOSE. Frequency doubling perimetry is a new psychophysical test procedure that is believed to be mediated by magnocellular (M-cell) mechanisms, and has been shown to be effective in rapid detection of glaucomatous visual field loss. The purpose of this study was to evaluate the influence of normal aging on frequency doubling contrast sensitivity, establish age-related normative values, and develop statistical indices of diffuse (widespread) and localized loss.
METHOD. Contrast thresholds were obtained for sixteen target locations throughout the central 25 degrees radius for a low spatial frequency (0.25 c/d) sinusoidal grating undergoing rapid (25 Hz) counterphase flicker, using a prototype developed by Welch Allyn, Inc. (Skaneateles Falls, NY). 253 normal subjects, approximately equally distributed from 16 to 85 years old, were tested at UC Davis and UC Berkeley. Subjects were required to have had a recent normal eye exam, normal visual fields (Humphrey 30-2) and no ocular or systemic disease. Statistical indices for Mean Deviation and Pattern Standard Deviation were calculated from this normative database.
RESULTS. Between ages 16 and 60, there was a linear decrease of 0.5 dB per decade for frequency doubling contrast sensitivity measures throughout the central visual field. Beyond 60, there was a suggestion of slightly greater sensitivity reduction with increasing age. There were no meaningful differences in contrast sensitivity as a function of visual field eccentricity. The between-subjects variability was approximately equal (standard deviation of about 1.5 dB) for all age groups.
CONCLUSION. Our findings provide a quantitative basis for statistical evaluation of frequency doubling perimetry in patients undergoing clinical screening for glaucomatous visual field loss. Examples of the use of this normative database and the statistical indices for evaluation of glaucoma and ocular hypertension patients will be presented. CAJ is a paid consultant fo
|Affiliation of Co-Authors||University of California, University of California, Ohio State University, University of California, University of California, University of California|