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See also comment(s) by William Swanson •
PURPOSE: To assess whether neuroretinal rim area (RA) measurements of the optic disc could be used to improve the estimate of the rate of change in visual field (VF) mean sensitivity in patients with ocular hypertension (OHT) using a Bayesian linear regression (BLR) compared to a standard ordinary least squares linear regression (OLSLR) of mean sensitivity (MS) measurements alone. METHODS: MS and RA measurements were analyzed from a longitudinal series of 179 patients with OHT visiting Moorfields Eye Hospital between 1992 and 2000. For each patient, linear regression of RA was computed after an appropriate transformation to 'scale' RA with MS measurements, and the slope coefficient from this regression was used as a prior for BLR of MS. The BLR was then compared with the OLSLR approach by evaluating how accurately each regression technique predicted future MS measurements. RESULTS: On average, BLR was significantly more accurate than OLSLR for series up to 8 measurements long (root-mean-square prediction error (RMSPE) was 0.14 dB smaller with BLR than OLSLR; p<0.001, Wilcoxon signed-rank test), with OLSLR of VF data alone being more accurate for longer series (RMSPE was 0.06 dB smaller with OLSLR than BLR). CONCLUSIONS: BLR provides a significantly more accurate estimate of the rate of change in MS than the standard OLSLR approach, especially in short time series, suggesting that structural measurements can be successfully used in statistical models to assist clinicians monitoring VF progression in patients with OHT. Further studies are necessary to validate the method in glaucoma patients.
Optometry and Visual Science, City University London, Northampton Square, London, EC1V 0HB, UK.
Full article6.20 Progression (Part of: 6 Clinical examination methods)
6.6.2 Automated (Part of: 6 Clinical examination methods > 6.6 Visual field examination and other visual function tests)