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PURPOSE: To measure progression of the visual field (VF) mean deviation (MD) index in longitudinal 10-2 VFs more accurately, by adding information from 24-2 VFs using Lasso regression. METHODS: A training dataset consisted of 138 eyes from 97 patients with glaucoma or ocular hypertension and a testing dataset consisted of 40 eyes from 34 patients with glaucoma or ocular hypertension. The Lasso method was used to predict total deviation (TD) values in training patients' 10-2 VFs based on information from their 24-2 VFs (52 TD values, foveal sensitivity and mean deviation MD). Then, the MD of each patient's 10-2 VF was estimated as the average of these Lasso-predicted TD values (10-2 VF 'Lasso MD'; LMD). Finally, linear regression was applied to each testing patient's series of longitudinal 10-2 VF MDs with and without additional Lasso-derived LMDs in order to predict future MDs not included in the regression analysis. Absolute prediction errors were compared when only actual 10-2 MDs were regressed against when a combination of actual 10-2 MDs and LMDs were regressed. RESULTS: The average absolute prediction error was significantly smaller for the novel method incorporating lMDS (Range: 1.6 to 1.8 dB) compared with the standard approach (range: 1.7 to 3.4 dB) (p<0.05, ANOVA test). CONCLUSIONS: Deriving 10-2 VF MD values from 24-2 VFs improves the prediction accuracy of progression. This approach will help clinicians to predict patients' visual function in the parafoveal area.
Department of Ophthalmology, University of Tokyo Graduate School of Medicine, Tokyo, Japan. rasaoka-tky@umin.ac.jp
Full article6.6.2 Automated (Part of: 6 Clinical examination methods > 6.6 Visual field examination and other visual function tests)
6.20 Progression (Part of: 6 Clinical examination methods)