Validation of the Iowa Head-Mounted Open-Source Perimeter

Area of Science:

• Ophthalmology
• Medical Devices
• Visual Science

Background:

• Traditional perimetry methods can be expensive and lack portability.
• Assessing visual field (VF) defects is crucial for diagnosing and monitoring eye conditions like glaucoma.
• The development of novel, accessible perimetry technologies is essential for expanding patient access to eye care.

Purpose of the Study:

• To validate visual field (VF) results obtained from the Iowa Head-Mounted Display (HMD) Open-Source Perimeter.
• To compare the test-retest repeatability and VF defect detection capabilities of the HMD perimeter against the Octopus 900 perimeter.

Main Methods:

• Twenty healthy participants and nine glaucoma patients underwent visual field testing using both the HMD and Octopus 900 perimeters.
• The Open Perimetry Interface platform, size V stimuli, a custom central 26° grid, and ZEST thresholding were employed.
• Historical data from the Humphrey Field Analyzer (HFA) were analyzed for comparison; repeatability was assessed using the repeatability coefficient (RC).

Main Results:

• Pointwise RCs for the HMD and Octopus 900 were 2.6 dB and 3.4 dB (healthy), and 4.2 dB and 3.5 dB (glaucoma), respectively.
• Limits of agreement between HMD and Octopus 900 were ±4.6 dB (healthy) and ±8.9 dB (glaucoma).
• VF defect detection was similar between the HMD and Octopus 900 for glaucoma patients.

Conclusions:

• The Iowa HMD Open-Source Perimeter demonstrates comparable repeatability to the Octopus 900.
• The HMD offers a more portable and cost-effective alternative to traditional perimetry devices.
• The study validates the HMD's visual field results, potentially increasing access to perimetry testing.