An Audiovisual 3D-Immersive Stimulation Program in Hemianopia Using a Connected Device

Abstract

BACKGROUND Homonymous hemianopia is a loss of conscious vision in one hemifield, strongly affecting everyday life. Audiovisual stimulation programs improve visual perception in the blind hemifield; however, they use large equipment operated in clinical settings. Such treatments require frequent visits at the clinic, hampering the patient's adherence and compliance. In one hemianopia patient, we tested a 4-week dynamic audiovisual rehabilitation program in the stand-alone, remotely controlled, virtual-reality, head-mounted display Oculus Go and measured the effect on visual perception. CASE REPORT A 15-year-old Caucasian male was diagnosed with a right homonymous hemianopia with splitting of central fixation after a traumatic occipital contusion at age 7 months. Visual assessment showed impaired binocular contrast sensitivity and retinal sensitivity. Fixation stability and visual fields were strongly affected. After a 4-week audiovisual rehabilitation program, including 3 hours 20 minutes of stimulation, the contrast sensitivity, fixation stability, and paracentral visual perception were significantly enhanced, improving quality of life. CONCLUSIONS This pioneering work reports the use of virtual-reality in a head-mounted display to provide an audiovisual stimulation protocol for low-vision rehabilitation in a hemianopia patient. Real-time data recording and remote control of the stimulation program demonstrate that such rehabilitation treatment can be performed by the patient at home without interruption of care, decreasing the burden of disease. Beneficial effects on visual function were measured according to clinical guidelines of low-vision assessment. Improvement in visual function and quality of life challenge the prevailing belief that post-acute vision loss is both permanent and unchangeable.

Figure 1.

Brain MRI without contrast. Axial T2 (A) and coronal T2 (B) indicating a left parietooccipital intraparenchymal hematoma.

Figure 2.

Contrast sensitivity measures. Graph representing contrast sensitivity in the right eye (OD – oculus dexter) (A) and left eye (OS – oculus sinister) (B) at baseline (gray line) and after treatment (black line). Gray shaded area represents the coefficient of repeatability, COR±0.24 logits.

Figure 3.

Principle of audiovisual stimulation (NeurofyResearch) program. Sequence of the visual task. (A) Eight yellow still spheres are present in a virtual cube. (B) One of these spheres turns red for 15 s (cued target) and returns yellow. (C) All spheres randomly move following linear paths across the visual field encompassing the blind field and bouncing on one another and on the walls of the virtual 3D cube when collisions occurred. (D) After 30 s, spheres stopped moving. (E) The patient had to select the cued target using a hand-guided laser pointer. (F) Correct selection was considered a positive hit.