The Incidence of Visual Field Defects at Each of 52 Locations in Standard Automated Perimetry in Glaucomatous Eyes. Data From the Diagnostic Innovations in Glaucoma Study (DIGS)

Abstract

Abstract: : Purpose: Phase 1 of a multi–stage analysis in Standard Automated Perimetry (SAP) to assess the likelihood of and relationship between defective visual field locations at various stages of disease. Methods: 212 glaucomatous eyes with repeatable SAP defects were stratified into 97 early (mean age 61.9 ± SD 12.5 years), 56 moderate (65.8 ± 13.4 years), and 59 severe (66.8 ± 12.5 years) by Hodapp–Anderson–Parrish severity criteria modified for 24–2 SAP full threshold. Abnormal visual fields were based on: PSD (pattern standard deviation) outside 5%, or GHT (glaucoma hemifield test) outside normal limits. Percentage of eyes with pattern deviation probability (PDP) below 0.5%, 1%, 2% and 5% were calculated for each location on the 24–2 grid. Results: There was no statistically significant difference in age among the three severity groups. All locations showed abnormalities in some percentage of eyes. However, the nasal step region (Cartesian coordinates, in degrees: N27/S3, N21/S3, and N21/S9) and superior arcuate hemifield (N15/S9) always showed the highest percentage of eyes with PDP probabilities triggered at each stage of disease. Points nearest fixation tended to be the least triggered (except N3/S3). The mean percentage of eyes with triggered PDP's for all locations increased with severity (ANOVA, F(2,153) = 107.2, p < .0001). Conclusions: The data suggest that all locations in the visual field may become defective with some locations in the nasal and superior regions being more likely than other locations. This data will be used to guide later stages of the development of Scotoma–Oriented PErimetry (SCOPE), a thresholding algorithm that places follow–up field locations relative to each individual's baseline scotoma.

Keywords: perimetry • visual fields