Pearls from the EGS Guidelines
Publishing date: February 2020
Visual field progression analyses may be event or trend-based. Trend analyses quantify rate of progression, usually by performing linear regression of global indices over time. Trend data can also be used to try to predict the future state of the visual field. Event analyses compare visual field tests to baseline to determine whether change has occurred. Eyes that show deterioration of at least 3 test locations are flagged as possibly progressing if the finding is repeated in 2 consecutive tests and likely progressing if repeated in 3 consecutive tests (1).
Commonly used event and trend analyses require at least 5 and preferably more tests, though progression may be detected before this. Ideally patients should be tested with standard automated perimetry 3 times per year during the first 2 years after diagnosis (2).
EGS Guidelines, 4th edition, Page 63.
1. Leske MC, Heijl A, Hyman L, Bengtsson B. Early Manifest Glaucoma Trial: design and baseline data. Ophthalmology 1999;106:11:2144-53.
2. Chauhan BC, Garway-Heath DF, Goni FJ, et al. Practical recommendations for measuring rates of visual field change in glaucoma. Br J Ophthalmol 2008;92:569-73.
Pearls Manager: Andrew Tatham