Study protocol for a randomized controlled trial of the NEIVATECH virtual reality system to improve visual function in children with anisometropic amblyopia

Abstract

Background Interest in developing alternative methods for the treatment of amblyopia has long been a topic of interest among clinicians and researchers, as prescribed occlusion and penalization therapies do not always provide an effective response and are associated with a high risk of recurrence and non-compliance. Here, we present the protocol of a small-scale RCT to evaluate the safety and clinical efficacy of a novel VR-based system designed to provide binocular vision training to children with anisometropic amblyopia. Methods We aim to recruit a total of 60 children with anisometropic amblyopia aged 5-17 years with no previous treatment for amblyopia other than refractive correction from the pediatric ophthalmology units of the University Clinical Hospital of Valladolid and the Vithas Medimar International Hospital of Alicante. Children who meet the eligibility criteria and consent to participate will be randomly assigned to a three-month intervention group of 18 half-hour in-office therapy sessions with the NEIVATECH system (group A) or to a parallel group receiving 2 hours of conventional patching per day at home for the same period of time (group B). Assessments of visual function will be carried out before the intervention and at 1, 2 and 3 months, with changes in distance BCVA being the primary outcome measure to be considered. Patient safety, compliance, satisfaction and acceptance to treatment will also be assessed after therapy as other valuable outcome measures. In addition, a rsfMRI scan will be performed on a subgroup of 5 patients from each group at the pre-intervention visit and at the post-intervention visit to test the effects of both therapies on neural plasticity in the visual cortex. Discussion The NEIVATECH system has been conceived as a serious game designed to provide binocular vision training to anisometropic amblyopic children by complementing the concepts of perceptual learning, dichoptic training and gamification in an immersive VR environment. We hope that this novel approach may lead to greater improvements in vision performance than those provided so far by conventional patching in anisometropic amblyopic children. Trial registration This protocol was registered with ClinicalTrials.gov (NCT04819386) on 29 March 2021.

Amblyopia Treatment through Immersive Virtual Reality: A Preliminary Experience in Anisometropic Children

“…In the case of study visits (visit 0, 1, and 2), the total examination time was about 1 h. A total of 18 sessions were performed during one month and a half, with at least three sessions per week. Training program protocol was previously described [ 28 ].…”

Current Developments in the Management of Amblyopia with the Use of Perceptual Learning Techniques

“…These principles applied in visual functions could be an effective treatment for amblyopia deficits. The effect of PL in shaping neural plasticity on the visual cortex and subsequent in rebalancing interocular dominance has been demonstrated in amblyopia patients through changes in the amplitude of steady-state visually evoked potentials (SSVEP) measured before and after a number of treatment sessions [25,26], while other researchers in an ongoing study aim to confirm the same effect by detecting changes in functional Magnetic Resonance Imaging (f-MRI) of treated patients [27].…”

“…One very popular form of PL is interactive video games, where different elements of the game are presented in each eye, and the player has to combine information from both eyes to interact accordingly and fulfill the game task. These games are designed as software applications either installed on a computer, tablet, smartphone, or game console or played online [25,27,31,33,39,[42][43][44]63]. Several studies evaluated the effectiveness of dichoptic video games for the treatment of amblyopia.…”

“…Virtual Reality/Augmented Reality Virtual reality (VR) is the presentation of a simulated 3D environment generated by a computer, projected before the patient's eyes on a head-mounted display [47]. It offers the patient a vivid, fully immersive experience, where he can actively interact with the software through multiple sensory functions, visual, auditory, and haptic [12,27,35,47,48]. Augmented reality (AR), on the other hand, is a live presentation of the real-world environment enhanced with additional digital elements projected over it [47].…”

“…Finally, an ongoing RCT with 60 naive pediatric participants aims to compare the effectiveness of a VR platform named NEIVATECH against traditional patching. Researchers intend to verify the impact of the treatment on neuronal plasticity in the visual cortex by performing functional MRI scans at pre-and post-intervention stages [27].…”