Classifying patterns of localized glaucomatous visual field defects on automated perimetry

Abstract

Aim: To classify the classic patterns of glaucomatous visual field defects on automated perimetry and to study their proximity to fixation.

Study design: Cross-sectional observational study.

Materials and methods: About 1120 full threshold 30-2 reliable visual fields of glaucoma patients were analyzed by 2 glaucomatologists. Classically described patterns of visual field defects were identified on the pattern deviation plot and definitions proposed. Interreader agreement between 3 independent (not involved in the classification) readers was determined. Proximity to fixation of the different patterns was assessed.

Results: Interreader agreement with 3 readers was found to be 93% or more between any 2 readers using the present system of classification. Central fixation was seen to be involved in 45% of the glaucomatous visual field defects studied overall.

Conclusions: The proposed definitions of topographical glaucomatous field defects based on the pattern deviation probability plot are simple to use in clinical practice with good interreader agreement.