Analysis Of Macular And Peripheral Choroidal Thickness In Astigmatic Anisometropic Amblyopia

Purpose: To analyze macular and peripheral choroidal thickness(CT)in astigmatic anisometropic amblyopia and the difference between amblyopic eyes and fellow and normal control eyes.Methods: A cross-sectional study was conducted in 60 patients with unilateral astigmatic anisometropic amblyopia;60 normal control groups were also included in the study.Three groups were divided.The choroid was scanned and measured by depth-enhanced imaging technology-optical coherence tomography(EDI-OCT).The following nine points were defined:subfoveal choroidal thickness(SFCT),superior nasal 0.5/1.5 mm(NS0.5/1.5),inferior nasal 0.5/1.5 mm(NI0.5/1.5),superior temporal0.5/1.5 mm(TS0.5/1.5)and inferior temporal 0.5/1.5 mm(TI0.5/1.5),and central macular thickness(CMT)was also measured.The CTs and CMT were compared and the age,gender,refractive status,best corrected visual acuity(BCVA)and biological parameters of eyeball were recorded.Results: CT at SFCT(344.86±71.04um),NS0.5(333.55±69.23um),NI0.5(324.27±65.57um),TS0.5(336.79±68.48um),TI0.5(338.99±69.80um),NS1.5(297.87±62.33um),NI1.5(280.20±59.68um)and TS1.5(331.63±63.94um)of amblyopia eyes was thicker than that of fellow and normal eyes(p < 0.05).CT at TI1.5(327.21±76.58um)was only thicker than normal eyes(p = 0.004).CMT of amblyopia eyes(218.522 ± 22.73um)was thicker than that of fellow and normal eyes(p < 0.05),but no significant difference in CT and CMT between fellow and normal eyes was found(p > 0.05).There was no significant difference in age,sex,spherical equivalent(SE)or axial length(AL)among the three groups(p > 0.05).SFCT correlated negatively with AL in all subjects(r =-0.434,p = 0.000;pearson correlation coefficient),and in the amblyopic eyes,fellow eyes and normal eyes respectively(r1 =-0.380,p1= 0.003;r2 =-0.470,p2 = 0.000;r3 =-0.480,p3 = 0.000;pearson correlation coefficient).Conclusions: CTs and CMT of astigmatic anisometropic amblyopia eyes were thicker than those of fellow eyes and normal eyes,and the difference is different in different regions.Studies have shown that the choroidal thickness of hyperopic anisometropic amblyopia is thicker than that of the contralateral eye and normal eye.This change was explained by AL or the underlying mechanism of amblyopia in some studies.However,astigmatism is purely refractive,with no obvious correlation with AL.It is speculated that choroidal changes may play an important role in the underlying mechanism of amblyopia,but further research on the pathogenesis of amblyopia is needed to prove.