Feasibility and Dynamic Range of Size-threshold Perimetry With the Iowa Head-Mounted Display Perimeter

The Iowa Head Mounted Open Source Perimeter uses a smartphone in a VR mount, which runs perimetric tests using the Open Perimetry Initiative software. Conventional luminance modulation is hampered by a smartphone's inability to generate low enough contrasts to accurately test normal subjects. Modulating stimulus size instead of luminance leverages the OLED display's excellent spatial resolution, and may reduce variability even in regions with lower sensitivity. An important validation step is to ensure the dynamic range of the test encompasses the continuum from normal to severely damaged.