Variability components of standard automated perimetry and frequency-doubling technology perimetry.

Abstract

For both SAP and FDT perimetry, variability occurring within a single test session contributed more to total variability than between-session variability. When the measurement scales available on commercial instrumentation were used, FDT perimetry exhibited significantly less variability than SAP, especially within regions of visual field sensitivity loss. FDT perimetry therefore shows promise as an effective test for detecting progressive glaucomatous visual field loss, although prospective longitudinal validation is still required to determine sensitivity to change.