Aims The purpose of this study was to explore the microstructural properties of the major white matter (WM) tracts in constant exotropia (XT) before and after strabismus surgery, and further investigate the association between microstructural alterations and the ocular dominance (OD). Methods We collected diffusion tensor imaging data of patients with XT before (n=19) and after (n=15) strabismus surgery and 20 healthy controls and evaluated OD and stereopsis. The probabilistic streamline tractography of the 24 major WM tracts was reconstructed by using the automated fibre quantification package. Fractional anisotropy and mean diffusivity (MD) along each tract were estimated, and their differences between the groups were examined. Furthermore, we evaluated the relationship between OD and the absolute value of altered microstructural parameters. Results While all postoperative XT patients restored normal stereopsis, most of their OD remained aberrant (9 out of 11). Compared with that of preoperation, the MD of postoperative patients decreased significantly along left anterior thalamic radiation (ATR), left arcuate fasciculus (AF), left corticospinal tract (CST), left cingulum cingulate (CGC) and left inferior fronto-occipital fasciculus. Moreover, OD was negatively correlated with the absolute value of MD changes in left ATR, left AF, left CST and left CGC. Conclusion Microstructural alterations after surgery in the visuospatial network tracts may contribute to the stereopsis restoration. Additionally, the results of the correlation analysis may signify that the balanced binocular input may be more conducive for the restoration and improvement of binocular visual function, including stereopsis. Thus, restoring normal ocular balance after surgical correction may be necessary to achieve more substantial improvements. No data are available.

中文翻译：

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斜视手术前后恒定外斜视主要白质束的显微结构特征

目的 本研究旨在探讨斜视手术前后恒定外斜视（XT）主要白质（WM）束的显微结构特征，并进一步探讨显微结构改变与眼优势（OD）之间的关系。方法 我们收集了 XT 患者在斜视手术前 (n=19) 和后 (n=15) 和 20 名健康对照者的弥散张量成像数据，并评估了 OD 和立体视觉。使用自动纤维量化包重建了 24 个主要 WM 束的概率流线束成像。估计了沿每个束的分数各向异性和平均扩散率 (MD)，并检查了它们之间的差异。此外，我们评估了 OD 与改变的微观结构参数的绝对值之间的关系。结果虽然所有术后 XT 患者都恢复了正常的立体视觉，但他们的大部分 OD 仍然异常（11 人中有 9 人）。与术前相比，术后患者左侧丘脑前放射（ATR）、左侧弓状束（AF）、左侧皮质脊髓束（CST）、左侧扣带回（CGC）和左侧额枕下束的MD显着降低。此外，OD 与左侧 ATR、左侧 AF、左侧 CST 和左侧 CGC 的 MD 变化的绝对值呈负相关。结论手术后视空间网络束的显微结构改变可能有助于立体视觉的恢复。此外，相关性分析的结果可能表明平衡的双眼输入可能更有利于双眼视觉功能的恢复和改善，包括立体视觉。因此，可能需要在手术矫正后恢复正常的眼部平衡以实现更实质性的改善。没有可用的数据。