The Potential of Virtual Reality for Inducing Neuroplasticity in Children with Amblyopia

Table 1

Summary of the clinical studies conducted to this date to evaluate the use of virtual reality technologies for the treatment of amblyopia.

Author (year)	Patients/groups	Age	Amblyopia type	Technology	Results	Follow-up
Waddingham et al. (2006) [64]	7 children	3 to 7 years	Residual amblyopia (anisometropic or strabismic with previous failed treatments)	I-BiT system (games and movie clips); Dichoptic	VA improvement from 6/12–6/120 pretreatment to 6/7.5–6/24–1 posttreatment; Total treatment time 4.4 hours; VA improvement in 5 out of 7 patients	7 to 15 sessions
Cleary et al. (2009) [65]	12 children	6.1 to 11.4 years	5 strabismic or mixed; 7 anisometropic-strabismic	I-BiT system (driving game and video clip); Dichoptic; 8 sessions, 25 min/session	58% sustained improvements in HCVA; 67% improvement in LCVA; Amblyopia eliminated in 2 patients; 5 children with VA 6/12 or better at 6 months after stopping treatment; HCVA improvement: 4 sessions; LCVA improvement: 7 sessions	18 weeks
Herbison et al. (2013) [66]	10 children	Mean 5.4 years	3 strabismic, 4 anisometropic and 3 mixed	I-BiT system (Nux game and video clip); Dichoptic; 6 weekly sessions, 30 min/session	78% showed VA improvement; 67% demonstrated a clinically significant increase in VA of ≥0.125 (0.175 to 0.300 LogMAR); Mean change from baseline to follow-up was 0.13 ± 0.14 logMAR	10 weeks
Herbison et al. (2016) [68]	75 children	4 to 8 years	67 were residual amblyopes and 70 had an associated strabismus	Randomised control trial with three arms: (i) DVD footage shown to the amblyopic eye and common background to both (I-BiT DVD); (ii) Modified shooter game, Nux, with sprite and targets presented to the amblyopic eye (I-BiT game); (iii) Both background and foreground presented to both eyes (non-I-BiT) games)	VA improvement in all three arms by approx. 0.07 logMAR; No difference between I-BiT DVD and non-I-BiT games compared with I-BiT games in terms of gain in vision	10 weeks
Cepeda-Zapata et al. (2019) [69]	45 students	17 to 28 years	Nonamblyopes	Conventional visual therapies implemented in virtual reality: brock cord, approach technique, and eccentric circles	Evaluation of simplicity and versatility for both clinician and infant patients; Pragmatic quality above average (1.73); Attractiveness (2.03) and hedonic qualities (1.90) above average	N/A
Ziak et al. (2017) [70]	17 adults	17 to 69 years	Anisometropic	Diplopia game + Oculus Rift OC DK2 head mounted display; 8 sessions, 40 min/session, twice per week; Dichoptic	Mean BCVA in amblyopic eye improved from 0.58 ± 0.35 before training to a posttraining value of 0.43 ± 0.38 (); Mean stereoacuity changed from 263.3 ± 135.1'' before dichoptic training to a value of 176.7 ± 152.4'' after training; 47.1% before dichoptic treatment had unmeasurable stereoacuity while this only occurred in 11.8% after training	1 month

VA, visual acuity; HCVA, high-contrast visual acuity; LCVA, low-contrast visual acuity.