HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Swanson, W. H. Articles by Fischer, S. E. Search for Related Content PubMed PubMed Citation Articles by Swanson, W. H. Articles by Fischer, S. E.

Quantifying Effects of Retinal Illuminance on Frequency Doubling Perimetry

From the Glaucoma Institute, SUNY State College of Optometry, New York, New York.

PURPOSE. To measure and quantify effects of variation in retinal illuminance on frequency doubling technology (FDT) perimetry.

METHODS. A Zeiss-Humphrey/Welch Allyn FDT perimeter was used with the threshold N-30 strategy. Study 1, quantifying adaptation: 11 eyes of 11 subjects (24–46 years old) were tested with natural pupils, and then retested after stable pupillary dilation with neutral density filters of 0.0, 0.6, 1.2, and 1.6 log unit in front of the subject’s eye. Study 2, predicting effect of reduced illuminance: 17 eyes of 17 subjects (26–61 years old) were tested with natural pupils, and then retested after stable pupillary miosis (assessed with an infrared camera). A quantitative adaptation model was fit to results of Study 1; the mean adaptation parameter was used to predict change in Study 2.

RESULTS. Study 1: Mean defect (MD) decreased by 10 dB over a 1.6 log unit range of retinal illuminances; model fits for all subjects had r² > 95%. Study 2: Change in MD (MD) ranged from –7.3 dB to +0.8 dB. The mean adaptation parameter from Study 1 accounted for 69% of the variance in MD (P < 0.0005), and accuracy of the model was independent of the magnitude of MD (r² < 1%, P > 0.75).

CONCLUSIONS. The results confirmed previous findings that FDT perimetry can be dramatically affected by variations in retinal illuminance. Application of a quantitative adaptation model provided guidelines for estimating effects of pupil diameter and lens density on FDT perimetry.

This article has been cited by other articles:

				A. Hot, M. W. Dul, and W. H. Swanson Development and Evaluation of a Contrast Sensitivity Perimetry Test for Patients with Glaucoma Invest. Ophthalmol. Vis. Sci., July 1, 2008; 49(7): 3049 - 3057. [Abstract] [Full Text] [PDF]

				P. H. Artes, D. M. Hutchison, M. T. Nicolela, R. P. LeBlanc, and B. C. Chauhan Threshold and Variability Properties of Matrix Frequency-Doubling Technology and Standard Automated Perimetry in Glaucoma Invest. Ophthalmol. Vis. Sci., July 1, 2005; 46(7): 2451 - 2457. [Abstract] [Full Text] [PDF]