Purpose
To describe eyes with preperimetric glaucomatous progression identified by automated alternation flicker (AAF), and to characterize visual field and optical coherence tomography (OCT) findings among these eyes.
Methods
In this cross-sectional investigation, baseline and follow-up optic nerve head photographs were obtained and used to create AAF images. Two masked graders (FS and NR) determined which eyes had evidence of glaucomatous structural progression. Eyes were included if they had a normal result on Humphrey Field Analyzer 24-2 SITA standard automated perimetry and a normal or borderline retinal nerve fiber layer (RNFL) thickness on OCT after the follow-up digital photograph. All interim and subsequent visual field and OCT results were reviewed for each eye to evaluate for progression and fluctuation of these parameters.
Results
Of 407 individuals considered for inclusion in this study, 115 met photographic and visual field inclusion criteria. Twenty eyes with structural progression were identified using AAF, with 18 of the eyes (90%) demonstrating neuroretinal rim loss and six (30%) developing RNFL defects. While all study eyes had normal visual fields at the time of follow-up photography, 7 (35%) developed subsequent abnormal fields. Eleven eyes (55%) underwent visual field fluctuation; nine eyes had at least one abnormal field prior to the normal field, while three had normalization after visual field progression. Five eyes (25%) with normal or borderline OCTs at the time of follow-up photography developed subsequent OCT abnormalities. Six eyes (30%) had OCT fluctuation; five had at least one abnormal OCT prior to the normal or borderline OCT, and one had normalization after an OCT abnormality.
Conclusions
AAF may allow for early detection of structural injury in glaucoma, prior to the onset of visual field and OCT abnormalities. In patients with preperimetric photographic progression, visual field and OCT findings often become abnormal or fluctuate.
Keywords: 629 optic nerve •
758 visual fields