NORMAL VISUAL-FIELDS MEASURED WITH OCTOPUS-PROGRAM G1 .2. GLOBAL VISUAL-FIELD INDEXES

To complement results from individual test locations, clinicians also evaluate indices, as they give a succinct overview of the visual field . This, however, requires exact knowledge of their variability. The pr esent study was designed to determine normal interindividual variabili ty of global visual field indices and incorporates a data base of a mu lticenter study performed with Octopus 201 perimeters using Program G1 . The 824 fields thus obtained included 139 fields of 139 healthy volu nteers who had undergone two previous visual fields and completed all three phases of program G1. The index mean sensitivity showed a signif icant and linear decrease with increasing age, 0.064 dB/year of life. The indices loss variance, corrected loss variance, and short-term flu ctuation did not correlate significantly with age. Percentiles are giv en for these visual field indices. While within the limits of normal v alues provided by the manufacturer for these indices, these results su ggest that visual fields with ''borderline'' values require further cl inical investigation in reliable, experienced subjects. The results ma y help clinicians to better evaluate global visual field indices and, therefore, to detect loss of visual function earlier.