Abstract
Purpose :
Saccadic eye movements can be impaired in amblyopia. In this study, a systematic review and meta-analysis was conducted to understand the extent to which saccadic latency (i.e., the time taken to execute an eye movement to perform a task) is impacted by anisometropic and strabismic aetiologies.
Methods :
A literature search was conducted for published studies that objectively measured saccades among different types of amblyopia in either children or adults. The relevant search used search engines such as PubMed, EMBASE and Scopus. Out of 244 retrieved full-text articles, we identified 30 case-control studies. Of these, 10 studies met our inclusion criteria by reporting saccadic latency values for incorporation into the meta-analysis for calculation of effect size (Hedges’ g) and heterogeneity (I2). These were further sub-grouped based on types of amblyopia (anisometropic and strabismic) and eye viewing (binocular, amblyopic and fellow eye viewing).
Results :
The overall impact of amblyopia on saccadic latency was large and significant, with a combined effect size of 2.47 and heterogeneity of 97.39%, derived from 455 amblyopes and 546 controls (p <0.0001), irrespective of the type of amblyopia and eye viewing. In both anisometropic and strabismic amblyopia, saccadic latencies were longest for the amblyopic eye, followed by binocular and fellow eye viewing. Among anisometropic amblyopes, the effect size and heterogeneity were 4.73 (I2 = 88.09%) for the amblyopic eye, 1.66 (I2 = 72.81%) for binocular viewing, and 0.29 (I2 = 95.25%) for the fellow eye viewing. Among strabismic amblyopes the effect size and heterogeneity for the amblyopic eye were 3.82 (I2 = 0), binocular viewing were 3.35 (I2 =94.03%), and fellow eye were -0.09 (I2 =97.63%).
Conclusions :
Irrespective of the underlying cause, amblyopia is associated with a delay in saccadic latency compared to controls. Saccadic latency is most delayed under amblyopic eye, as opposed to binocular and fellow eye viewing.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.