Beyond vision: collaboration between physical therapy and neuro-optometry in assessment and treatment of visual perceptual deficits using immersive virtual reality

Describe key assessments and high- and low-tech interventions to treat visual-vestibular and visual-perceptual disorders.

Binocular vision assessment includes the cover test, near point of convergence test, depth perception testing, convergence/divergence testing, near/far accommodation, and phoria testing. Errors in spatial orientation, shifted perception, depth perception, and abnormal perception of vertical (SVV) or horizontal (SVH) contribute to errors in postural adjustments. While the low-tech “bucket test” is used to determine the static SVV, using a head-mounted virtual reality (VR) display (HMD) allows the clinician to change the type and direction of various backgrounds to determine the dynamic SVV which has been correlated with increased ROF⁷. Visual vertigo is due to a conflict between the visual and vestibular systems or between our peripheral and central vision systems. Dizziness or imbalance is triggered by complex visual environments (busy patterns, “grocery store syndrome”, moving objects) and is treated by strategies to desensitize the brain to these visual stimuli and improve balance.

VR posturography and HMD systems allow the clinician to incrementally and precisely control multisensory input, including speed, content, contrast, direction, and field of view of the visual stimulus and combine these features with cognitive processing tasks (dual task, response inhibition, spatial memory, perceptual memory span, reaction time). Low-tech rehabilitation approaches focus on habituation, gaze stability, balance, multisensory integration, optokinetic stimulation, corrective lenses and prisms to improve visual alignment, medication, cognitive behavioral therapy or environmental modifications^8.9.

Interprofessional collaboration permits a comprehensive approach to treat visual perceptual, binocular, and visual-vestibular impairments to reduce ROF. Immersive VR creates a full-view immersive environment with precise control over optic flow, peripheral and central vision, movement speed, cognitive processing and multisensory integration.

Rehabilitation focusing on both motor deficits and visual perceptual factors enables task-oriented motor learning transfer from clinic to real life. VR promotes greater neuroplasticity in motor planning and movement.