Circular Contrast Perimetry via Web Application

Abstract

Purpose: The purpose of the study was to compare a novel, 24°, 52-locus online circular contrast perimetry (OCCP) application against standard automated perimetry (SAP) in terms of both diagnostic accuracy and patient attitudes. Design: This was a cross-sectional study. Subjects: Ninety-five participants (42 controls and 53 open-angle glaucoma patients) were included. Methods: Participants performed both perimetry tests and then completed an online survey. Subjective feedback responses were collected. Main Outcome Measures: Agreement, sensitivity, specificity, and area under receiver operating curves (AUCs) were compared for the parameters of OCCP, SAP, and OCT for the retinal nerve fiber layer (RNFL) and macular ganglion cell complex inner plexiform layer (GCC + IPL). Participant attitudes toward the OCCP test versus the SAP test, in both glaucoma patients and controls, were compared. Rasch analysis assessed the psychometric properties of the survey and intergroup variability. Results: The AUC for OCCP mean deviation (MD) was 0.959 ± 0.02. Compared with other instruments’ parameters with the highest AUC, it was superior to SAP MD (0.871 ± 0.04, P = 0.03) and OCT GCC + IPL (0.871 ± 0.04, P = 0.03) and similar to OCT RNFL inferior thickness (IT) (0.917 ± 0.03, no significance). Online circular contrast perimetry pointwise sensitivity was less than SAP by 4.30 dB (95% confidence interval = 4.02–4.59); 95% limits of agreement ranged from −6.28 to −2.33 dB. At the best cutoff, the OCCP MD had a sensitivity of 98% and specificity of 85% for detecting glaucoma. Cohen's kappa demonstrated good agreement with SAP MD (0.69) and OCT RNFL IT (0.62) and moderate agreement with OCT GCC + IPL IT (0.57). Participants preferred OCCP across most survey parameters (P < 0.0001). Rasch analysis demonstrated no differential item functioning for clinical group, gender, or age. Conclusions: With similar diagnostic metrics to SAP, OCCP offers an improved user experience with the potential to increase the provision of care and improve disease surveillance outcomes.

Keywords

• Glaucoma
• Perimetry
• Visual field test