Glaucoma causes peripheral vision loss and impaired driving performance. We developed a novel driving simulator visual field task (DSVF) in a panoramic driving simulator to map the available field of view under different perceptual task loads in naturalistic settings. Our hypothesis is that “available field of view” will decrease with increasing task load in both glaucoma subjects and controls. This is a cross-sectional study with 28 glaucoma subjects and 19 controls. DSVF (60̊ x 20̊ visual field at 2.5 m) was tested in a high-fidelity interactive driving simulator in 4 different scenarios: a) no distractions b) no driving condition with unrestricted head/eye movements c) driving d) driving with PASAT (Paced Auditory Serial Addition Test). Each test was repeated twice. The main outcome measure was a visual field index (DSVF-VFI). DSVF-VFI was compared to the Humphrey Visual field -HVF-VFI monocularly and binocularly to validate the test. The DSVF task was highly reproducible and comparable to HVF. An A-pillar scotoma appeared in all DSVF trials. In both glaucoma subjects and controls, the DSVF-VFI decreased with increasing task load. The DSVFI decreased significantly more in the glaucoma group as compared to the control group. We developed a predictive formula to predict available field of view while driving from clinic based HVF. Glaucoma subjects were impaired in completing multiple task demands, such as driving and DSVF- either because a) compensation for peripheral vision loss acts as a continuously present load on attention capacity b) glaucoma is associated with diminished cognitive capacity as compared to controls
