屈光参差性弱视与斜视性弱视患儿视放射发育情况对比研究:基于扩散张量成像检查

Comparison of optic radiation between anisometropic and strabismic amblyopia based on diffusion tensor imaging

目的利用扩散张量成像(DTI)检查单眼屈光参差性弱视与斜视性弱视患儿视放射发育情况,比较两种弱视患儿视觉损害发生机制的异同。方法对屈光参差性弱视组12例左眼弱视患儿、斜视性弱视组12例左眼弱视患儿以及正常对照组15名儿童进行DTI程序扫描,采集所有儿童两侧视放射的各向异性分数(FA)、平均扩散率(MD),对左右侧视放射FA及MD分别行独立样本t检验,对各组儿童不同部位数据行单因素方差分析,比较两种类型弱视患儿视放射的发育情况。结果正常对照组儿童的FA及MD右侧均略高于左侧,差异均无统计学意义(均为P>0.05);屈光参差性弱视组患儿右侧FA(0.469±0.012)高于左侧(0.460±0.013),右侧MD(0.872±0.015)低于左侧(0.888±0.039),差异均有统计学意义(均为P<0.05);斜视性弱视组患儿右侧FA(0.475±0.013)低于左侧(0.496±0.015),右侧MD(0.871±0.012)高于左侧(0.863±0.015),差异均有统计学意义(均为P<0.05)。与正常对照组儿童相比,屈光参差性弱视组患儿双侧视放射FA降低、MD升高,差异均有统计学意义(均为P<0.05);与正常对照组相比,斜视性弱视组患儿双侧视放射FA均降低,右侧视放射MD增高,差异均有统计学意义(均为P<0.05),左侧视放射MD差异无统计学意义(P>0.05)。两种类型弱视患儿比较左侧视放射FA、MD差异均有统计学意义(均为P<0.05),右侧视放射FA、MD差异均无统计学意义(均为P>0.05)。结论DTI可以无创地观察弱视患儿视放射微观结构的改变,为弱视发病机制的研究提供了新的思路和工具。

Objective To detect the development of visual radiation in children with anisometropic amblyopia and strabismic amblyopia by diffusion tensor imaging(DTI),and to compare the differences and similarities in the mechanism of visual damage between the two kinds of amblyopia.Methods Twelve children patients of left-eye amblyopia in anisometropic amblyopia group,12 children patients of left-eye amblyopia in strabismic amblyopia group and 15 children of normal control group were scanned by DTI program,and the values of anisotropy fraction(FA)and average diffusivity(MD)of bilateral visual radiation were collected.Independent t samples were tested for FA and MD of left and right side-view radiation,and univariate variance analysis was performed on the data of each part of the three groups to analyze and compare the development of visual radiation of two types of amblyopia patients.Results FA and MD values of normal control group were slightly higher on the right side than on the left side,and there was no significant difference(both P>0.05).In anisometropic amblyopia group,the FA value on the right side(0.469±0.012)was higher than that on the left side(0.460±0.013),and the MD value on the right side(0.872±0.015)was lower than that on the left side(0.888±0.039),with statistical differences(both P<0.05).In strabismus amblyopia group,FA value on the right side(0.475±0.013)was lower than that on the left side(0.496±0.015),MD value on the right side(0.871±0.012)was higher than that on the left side(0.863±0.015),and the differences were statistically significant(both P<0.05).Compared with the normal controls,the FA value of bilateral visual radiation in anisometropic amblyopia group decreased and MD value increased,with statistical differences(both P<0.05).Compared with the normal control group,the FA value of bilateral visual radiation in strabismus amblyopia group decreased with statistical differences(P<0.05),while the MD value of right visual radiation increased with statistical difference(P<0.05),but the MD value of left visual radiation had no statistical difference(P>0.05).Comparing the two types of amblyopia,there were statistical differences in FA and MD of left visual radiation(both P<0.05),but no statistical differences in FA and MD of right visual radiation(both P>0.05).Conclusion DTI can observe the changes in visual radiation microstructure non-invasively,which provides a new perspective and tool for the research of amblyopia pathogenesis.