Glaucoma: Confrontation visual field test using Bagolini striated glasses — a new screening method for detecting visual field defects

Abstract

INTRODUCTION. Glaucoma diagnosis is based on elevated intraocular pressure, altered morphology of the optic disc, and perimetric visual field defects. Next to funduscopy and optical coherence tomography, perimetric data are important. In developing countries, large parts of the population have only limited access to medical care. Especially in these cases, a quick and affordable method for detecting visual field defects would be desirable. The aim of this study was to investigate the potential use of Bagolini striated glasses in detecting glaucomatous visual field defects.

MATERIALS AND METHODS. Ninety subjects of the Erlangen Glaucoma Register (ISSN 2191-5008, CS-2011. ClinicalTrials.gov, Identifier: NCT00494923) were tested using the confrontation visual field test with Bagolini striated glasses [10 normals, 17 ocular hypertensions (OHT), 31 preperimetric open-angle glaucomas (preOAG), 16 normal tension glaucomas (NTG), 16 open-angle glaucomas (OAG)]. All probands underwent standard ophthalmological examination including slit-lamp biomicroscopy, funduscopy, and Goldmann-tonometry. Additionally, standard white-on-white perimetry and measurements of the global retinal nerve fibre layer (RNFL) of the optic disc were performed.

RESULTS. 1. All normals, all OHTs, and 96% of preOAGs showed normal Bagolini test results. 2. 74% of NTGs and 73% of OAGs yielded pathological Bagolini test results. 3. Specificity of patients with normal visual fields was 98% and sensitivity was 73–80%. 4. Visual field defects resulted in altered Bagolini test results. 5. Localised visual field defects were detected in 78% (NTG) and 80% (OAG) using Bagolini striated glasses.

CONCLUSIONS. Glaucoma-related visual field defects can be detected by confrontation visual field testing using Bagolini striated glasses. This quick, easily performed, and affordable method can be used as a bedside test and is suitable as a screening method for persons in developing countries.