Perimetry of the Central Visual Field Using a Head-Mounted Open-Source Perimeter in Patients with Inherited Retinal...

Area of Science:

• Ophthalmology
• Medical Technology
• Visual Science

Background:

• Head-mounted perimeters (HMPs) utilize consumer electronics for affordable visual field testing.
• HMPs have not yet been validated for patients with inherited retinal diseases (IRDs).

Purpose of the Study:

• To pilot-test the Iowa-HMP system for visual field assessment in patients with IRDs.
• To compare the Iowa-HMP's performance against a standard Octopus 900 perimeter.

Main Methods:

• The Iowa-HMP, comprising a smartphone, headset, and open-source software, was used.
• The 10-2 grid and ZEST algorithm were employed with a 10 cd/m² background.
• Testing included one normal subject and patients with macular dystrophy, Stargardt's disease, and retinitis pigmentosa.

Main Results:

• Typical visual field loss patterns were discernible with the Iowa-HMP.
• The Iowa-HMP demonstrated a dynamic range of 14 to 30 dB sensitivity.
• Limits of Agreement were ±7.5 dB, with diagnostic sensitivity of 0.67 and specificity of 0.95 for detecting low sensitivity locations.

Conclusions:

• The Iowa-HMP shows potential for visual field testing in IRDs, particularly for research.
• Open-source software facilitates further investigation in this field.
• Direct comparison with standard perimetry is limited due to the HMP's dynamic range.