Abstract
Visual field assessment, or perimetry, poses a surprisingly rich set of interesting problems. Current standards of care include Zeiss’s Humphrey Visual Field Analyzer (HVFA) and Haag-Streit’s Octopus. These de facto standards allow comparison across time and between examinees, but they are labor-intensive to use, bulky, and expensive. In addition, the tests are not optimally designed from a psychophysical point of view. We describe psychophysical improvements in a new, head-mounted VR displays for perimetry. To disambiguate false alarms we use an nAFC task rather than a go/no go button press; to improve fixation we do not require suppression of the orienting reflex, and use a high acuity task at fixation rather than instructions to fixate; we use binocular viewing because monocular patching increases the gain on neural noise from the occluded eye; we use blurred decrement stimuli rather than small increment stimuli, and target sizes and contrasts that equate visibility across the normal visual field. The new test has surprising spatial precision in normally sighted individuals, and visual field maps in patients with disease look similar to traditional test results. Portability, low cost, low discomfort, and ease of use make it feasible for patients to test themselves frequently at home. Disclosure: the author is an employee of Vivid Vision, Inc., which is developing the new test as a commercial product.