Appearance of the Pattern Deviation Map as a Function of Change in Area of Localized Field Loss

Abstract

The localized component of field loss in glaucoma produced an overestimation of diffuse loss and a consequent underestimation of the severity of focal loss by PD analysis. This effect increased as the spatial extent of the loss became more extensive and will lead to an underestimation of progressive localized field loss.

An Update to Octopus Perimetry

“…Henson et al 18 showed that in early glaucoma even the first 10 ranks show reduced sensitivity and thus the calculation of DD. Asman 19 21 and found less influence. Figure 2c shows the integration of local loss.…”

Performance of glaucoma progression analysis software in a glaucoma population

“…Pattern deviation analysis generally yields a smaller number of eyes with progression than total deviation analysis, as it does not account for diffuse loss from cataract progression [6,7] or for the diffuse glaucoma progression that differs from classical focal glaucomatous visual field deterioration [5]. In addition, in patients with moderate or advanced damage, pattern deviation calculations can also underestimate and bias the results [12,13]. However, there is a subset of patients that show progression with pattern deviation analysis and not total deviation analysis, because the former method may compensate for an overall improvement in the visual fields resulting from learning effects or inappropriate age adjustment [7].…”

Stabilization and comparison of TOP and Bracketing perimetric strategies using a threshold spatial filter

“…It could be thought that this unequal increase could induce differences in the NPP calculated as pattern deviation, since there is a known dependence relationship between the number of local defects and the diffuse component of visual field loss [2]. However, this does not occur.…”