Using the 24-2 Sita Fast Humphrey to Detect Visual Field Defects Noted in Patients with Neurological Lesions Impacting the Visual Field NormallyAssessed by Octopus Visual Field Testing

Abstract

Objective: To investigate the validity of the 24-2 SITA fast Humphrey Visual Field (HVF) testing compared to the established parameters of Octopus Visual Field (OVF) for detecting and monitoring patients with neurologic pathology impacting visual fields Design: Retrospective chart review. Participants: 108 adult patients derived from the Eye Institute of Alberta (EIA) database. Methods: Study participants included adults with OVF testing, at the EIA between September 2015 to September 2017. Three blinded reviewers assessed if findings from each OVF would be identifiable on 24-2 SITA fast HVF testing based on established standardized degree of visual field cut-offs. Demographic data and level of agreement were measured using basic descriptive statistics. Results: In total, 211 individual eye OVFs were scored. Based on our established measurements the 24-2 SITA fast HVF would have identified clinically relevant findings on visual field testing in 197 (93.4%) participants. Of the 6.4% not detected, 64% were due to the patient being unable to fixate on a I2e or I4e isopter, with an additional 18% suffering from movement disorders resulting in exam difficulty (i.e. Parkinson’s disease). Conclusion: The 24-2 SITA fast HVF has potential to be an appropriate alternative test to OVF for detecting and monitoring patients with neurologic pathology impacting visual fields. However, patients with severe vision loss or those not able to fixate on isopters I4e and lower would benefit from more robust testing available in OVF formats. Further head to head comparison of the two visual field modalities is warranted in this group of patients