Short-Term Safety Evaluation of a Multi-Pressure Dial: A Prospective, Open-label, Non-randomized Study

INTRODUCTION: Prospective, open-label, non-randomized, single site study to assess the safety and tolerability of a multi-pressure dial. METHODS: 30 healthy subjects received application of negative pressure (–15 mmHg) in one eye for 30 minutes and ambient atmospheric pressure in the contralateral eye. To evaluate safety, the primary outcome measures included best corrected visual acuity (BCVA), intraocular pressure (IOP) changes from baseline, slit-lamp and dilated fundus examination findings, and rate of adverse events. Exploratory analyses included in this study also evaluated changes from baseline measurement in tear break-up time (TBUT) and RNFL thickness measured by OCT. In addition to baseline screening, subjects underwent testing and negative pressure application on day 0 and returned 1 week after the initial visit for clinical testing. The follow-up visit did not include use of the multi-pressure dial (MPD) but repeated baseline testing and evaluated for adverse events. RESULTS: No adverse events were reported in the study. After short-term wear of the MPD on day 0, there was a minimal but statistically significant increase of half a line (LogMAR) in BCDVA for study eyes; this increase was not present at 1 week. There were no observed changes in cup-disk ratio and TBUT 1 week after the initial testing. There was a statistically significant pressure reduction in both study and fellow eyes at 1 week following the study, but clinical significance has yet to be determined. CONCLUSION: The MPD, which consists of a pair of goggles connected to a handheld, programmable pump, was well tolerated by subjects enrolled in the study. Key safety parameters remained stable after short-term exposure. The favorable safety results of this study support the safety profile of the MPD and promote further investigation of the device as a potential treatment of glaucoma. FUNDING: Equinox Ophthalmic, Inc. (Newport Beach, CA).