Diagnostic Power and Reproducibility of Objective Perimetry in Glaucoma

Abstract

Précis: An objective perimetry method provides four 30-2 style reports in 8 minutes. These comprise sensitivity and delay reports for both eyes. A combined report format shows comparable diagnostic power to two forms of automated perimetry. Purpose: To compare objective perimetry with two forms of standard automated perimetry (SAP) in glaucoma. Methods: The study cohort contained 40 persons with glaucoma (PwG) and 94 normal control subjects. The PwG had both perimetric and pre-perimetric eyes. Multifocal pupillographic objective perimetry was performed with the objectiveField Analyser® (OFA®), which independently assesses the visual fields of both eyes concurrently. Its OFA30 test assessed the central ±30°, and the OFA15 test assessed the central ±15°, both providing 30-2 style reports. The OFA tests were repeated two weeks apart to assess test-retest variability (TRV). OFA was compared with Matrix and HFA-SITA fast 24-2 threshold testing. Diagnostic power was quantified as area under receiver operating characteristic curves (AUROC). Test durations, Mean Defects and Pattern Standard Deviations of the 4 tests were compared. Results: At a median of 4.09±0.02 minutes/eye the OFA tests were quicker than SAP (all P≤0.0001), 2 minutes/eye if OFA per-region sensitivities and delays are considered separately. The %AUROCs for OFA, Matrix and HFA were not significantly different, averaging 93±3% (mean±SD) in perimetric eyes, and 73±6% in pre-perimetric eyes. For moderate to severe fields OFA TRV was less than published results for SAP. OFA30 mean defects were significantly correlated between repeats (r=0.91), and with OFA15 (r=0.93, both P<0.0001). Conclusions: OFA provides extra functional measures in the form of per-region delays, and between-eye asymmetries. Both the OFA wide-field and macular tests provided comparable diagnostic power to SAP and better TRV in damaged eyes.