A Meta-Analysis of Choroidal Thickness Changes in Unilateral Amblyopia

To date, the topic of amblyopic changes remains controversial. Therefore, a systematic review and meta-analysis were carried out to evaluate choroidal changes in unilateral amblyopia.

Major literature databases were searched for amblyopia-relevant studies. Using enhanced depth imaging optical coherence tomography (EDI-OCT), the primary outcome parameters examined were subfoveal choroidal thickness (SFCT) and different choroidal thickness (CT) positions. Efficacy estimates were evaluated by weighted mean difference (WMD) and 95% confidence interval (CI) for choroidal-associated changes. We performed subgroup analysis and metaregression analysis to examine potential sources of heterogeneity.

Eleven cross-sectional studies that included a total of 768 participants were identified. The amblyopic eye SFCT was thicker than that of the fellow and control (normal) eyes (WMD_{amblyopia versus fellow} = 49.24, 95% CI of 30.22 to 68.27, p < 0.001; WMD_{amblyopia versus control} = 54.51, 95% CI of 32.17 to 76.85, p < 0.001). There were no differences between the fellow and control eyes (WMD = 13.81, 95% CI of 1.16 to 28.77, p = 0.071). Subgroup and metaregression analyses indicated that the OCT type was the main source of heterogeneity.

The CT in the amblyopic eyes was thicker than that in the fellow and control eyes.