Dp. Crabb et al., NEW APPROACH TO ESTIMATING VARIABILITY IN VISUAL-FIELD DATA USING AN IMAGE-PROCESSING TECHNIQUE, British journal of ophthalmology, 79(3), 1995, pp. 213-217
Aims-A new framework for evaluating pointwise sensitivity variation in
computerised visual field data is demonstrated. Methods-A measure of
local spatial variability (LSV) is generated using an image processing
technique. Fifty five eyes from a sample of normal and glaucomatous s
ubjects, examined on the Humphrey field analyser (HFA), were used to i
llustrate the method. Results-Significant correlation between LSV and
conventional estimates - namely, HFA pattern standard deviation and sh
ort term fluctuation, were found. Conclusion-LSV is not dependent on n
ormals' reference data or repeated threshold determinations, thus pote
ntially reducing test time. Also, the illustrated pointwise maps of LS
V could provide a method for identifying areas of fluctuation commonly
found in early glaucomatous field loss.