Risk of Airborne COVID-19 Transmission While Performing Humphrey Visual Field Testing.

PRECIS: Designing and demonstrating an experiment that shows the risk of airborne transmission of COVID-19 between patients having visual fields analyzed is low. PURPOSE: The aim was to investigate the possibility of airborne transmission of COVID-19 during Humphrey visual field testing in a real-world scenario. METHODS: A particle counter was placed within the bowl of Humphrey visual field analyzer (HFA) before and after turning on the machine to ascertain the effect of the air current produced by the ventilation system on aerosols. A second experiment was run where the particle counter was placed in the bowl and recorded particulates, in the air, as a 24-2 SITA standard was performed by a mock patient and then again immediately after the patient had moved away. We measured aerosol particle counts sized ≤0.3 µm, >0.3≤0.5 µm, >0.5≤1 µm, >1≤2.5 µm, >2.5≤5 µm, and >5≤10 µm. RESULTS: Particulates of all sizes were shown to be significantly reduced within the bowl after turning the machine on, demonstrating that the air current produced by the HFA pushes air out of the bowl and it cannot stagnate. There was no significant difference in measurement of aerosol while there was a patient performing the test and immediately after they had moved away, suggesting that aerosols breathed out by the patient are not able to remain in suspension in the bowl because of the ventilation current. CONCLUSION: There is no significant difference between aerosol count in the bowl of a HFA before, during and after testing. This suggests the risk of airborne transmission of COVID-19 is low between subsequent patients. This is in keeping with manufacturer's guidance on Humphrey visual field testing.

Home Monitoring for Glaucoma: Current Applications and Future Directions.

Technological advances provide a number of options for glaucoma monitoring outside the office setting, including home-based tonometry and perimetry. This has the potential to revolutionize management of this chronic disease, improve access to care, and enhance patient engagement. Here, we provide an overview of existing technologies for home-based glaucoma monitoring. We also discuss areas for future research and the potential applications of these technologies to telemedicine, which has been brought to the forefront during the ongoing COVID-19 pandemic.

The Impacts of Face Mask Use on Standard Automated Perimetry Results in Glaucoma Patients.

PURPOSE: The coronavirus disease 2019 (COVID-19) spread rapidly worldwide, causing a severe outbreak. Because the disease is easily transmitted, face masks are a vital tool to slow the spread. The aim of this study is to investigate the impacts of face mask use on standard automated perimetry (SAP) results in glaucoma patients. MATERIALS AND METHODS: All follow-up glaucoma patients who underwent SAP between May and October 2020 were enrolled in this study. In patients with low test reliability and/or visual field changes, SAP was repeated after repositioning and taping patients' face masks. RESULTS: A total of 127 patients (59 female and 68 male) with a mean age of 59.8±10.3 years were included in the study. While 101 patients (79.5%) wore surgical face masks, 26 patients (20.5%) wore cloth face masks. Low SAP reliability appeared in 23 patients (18.1%), and inferior visual field defects were present in 3 patients (2.4%). The main effects of poorly fitting face masks on SAP reliability were increased fixation losses and false-positive errors (for both, P=0.001). Low SAP reliability was significantly higher in patients wearing cloth face masks than in those wearing surgical face masks (47.8% vs. 9.9%; P=0.0001). The face mask-related fogging of eyeglasses before SAP is a strong predictor of fogging of the trial lenses-related low SAP reliability (odds ratio: 27, 95% confidence interval: 5.48-132.92, P=0.0001). In all repeated SAPs, the patients' reliability parameters improved, and inferior visual field artifacts disappeared. CONCLUSIONS: Unsuitable face masks can cause either visual field artifacts, which may be interpreted as glaucoma progression or low test reliability. Taping the face masks' upper edges is an effective technique to prevent visual field artifacts and obtain good test reliability.