Abstract
Purpose :
Perimetry is a mainstay in the diagnosis and monitoring of glaucoma. The current standard-of-care standard automated perimeter (SAP), the Humphrey Field Analyzer (HFA, Carl Zeiss AG, Oberkochen, Germany), is a large device that does not allow for examination outside the clinic and can be uncomfortable for patients with limited mobility or large body habitus. The present study attempted to validate a novel head-mounted perimeter, the Smart System Virtual Reality Headset (SSVR, M&S Technologies, Niles IL), against the HFA as an alternative method of visual field testing.
Methods :
This prospective interventional study was conducted on a total of 13 eyes from 7 subjects recruited from the University of Iowa Hospitals and Clinics. Subjects were randomized to complete HFA followed by SSVR, or vice-versa. The HFA used a 24-2 Swedish interactive thresholding algorithm (SITA) Standard testing algorithm. The SSVR used a 24-2 Neighborhood-Zippy Estimation by Sequential Testing (ZEST) testing algorithm. Following visual field testing, subjects completed a survey regarding their subjective experience using each perimeter. Main outcome measurements included mean deviation (MD), pattern standard deviation (PSD), foveal threshold (FT), and test duration (TD). Statistical analyses were performed using Student paired t-tests (a=0.05).
Results :
MD was not significantly different between the SSVR (-9.40±6.81 dB) and HFA (-8.37±6.60 dB, p=0.118, CI=-2.36, 0.30). PSD was not significantly different between the SSVR (5.65±2.40 dB) and HFA (6.99±3.98 dB, p=0.109, CI=-3.02, 0.35). FT was significantly different between the SSVR (18.19±8.00 dB) and HFA (31.9±2.79 dB, p=<0.001, CI=-17.66, -9.65). TD was significantly different between the SSVR (335.00±90.29 s) and HFA (384.85±62.13 s, p=0.028, CI=-93.22, -6.47). When rating the comfort of each perimeter, 87.5% of subjects reported the SSVR was “comfortable” or “very comfortable” versus 12.5% for the HFA. When presented with a forced choice, 87.5% of subjects preferred the SSVR to the HFA.
Conclusions :
The SSVR was a reliable alternative to SAP using the HFA for testing MD and PSD. The SSVR was not a reliable alternative to the HFA for testing FT. TD was shorter using the SSVR versus the HFA, which will likely improve the patient testing experience. Subjectively, the SSVR was reported to be more comfortable than the HFA and was the preferred perimeter for future visual field testing.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.