Purpose

To present a case of activation of Leber hereditary optic neuropathy (LHON) following head and ocular trauma of the fellow eye in the patient with no remarkable symptoms and normal visual acuity prior to trauma.

Case summary

A 31-year-old healthy man was referred to our hospital after a traffic accident. He had blowout fractures of medial and inferior orbital wall of the left eye, subcutaneous hematoma of the left forehead, and bony fragment that compressed the left optic nerve. Initially, best-corrected visual acuity (BCVA) was 20/20 in the right and 20/1000 in the left eyes. Relative afferent pupillary defect of the left eye was apparent, and fundus examination revealed choroidal rupture circumferentially crossing the macular area. Nine months later, the patient complained with gradual vision loss in the right eye, which was the contralateral eye of the ocular trauma. BCVA was 20/200, and perimetry revealed cecocentral scotoma in the right eye. BCVA in both eyes reduced to 20/2000 1 year post-trauma. Visual evoked potentials revealed markedly decreased in amplitudes and elongated latencies for both eyes. Mitochondrial DNA analysis revealed a G11778A mutation; therefore, a diagnosis of activation of LHON followed by trauma was made for the previously unaffected carrier.

Conclusions

This is a case in which activation of LHON occurred in a healthy carrier following head and ocular trauma of the fellow eye. This observation suggests the possibility that LHON activation in healthy carriers may occur in patients who experience head or ocular trauma even in the fellow eye.

中文翻译：

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对侧眼头部外伤和眼外伤后Leber遗传性视神经病变一例

目的

介绍一例对侧眼头部和眼部外伤后 Leber 遗传性视神经病变 (LHON) 激活的病例，该患者在外伤前没有明显症状且视力正常。

案例总结

一名 31 岁健康男性因交通事故被转诊至我院。左眼眶内壁和下眶壁爆裂性骨折，左前额皮下血肿，骨碎片压迫左视神经。最初，最佳矫正视力 (BCVA) 右眼为 20/20，左眼为 20/1000。左眼相对传入性瞳孔缺损明显，眼底检查显示脉络膜破裂周向穿过黄斑区。九个月后，患者主诉右眼视力逐渐下降，这是眼外伤的对侧眼。BCVA 为 20/200，视野检查显示右眼有盲肠中央暗点。双眼 BCVA 在创伤后 1 年降至 20/2000。视觉诱发电位显示双眼的振幅显着降低，潜伏期延长。线粒体 DNA 分析显示 G11778A 突变；因此，对先前未受影响的携带者做出了 LHON 激活后继受创伤的诊断。

结论

这是一个健康携带者在另一只眼睛的头部和眼部创伤后发生 LHON 激活的情况。这一观察结果表明，即使在对侧眼睛也有头部或眼部创伤的患者中，健康携带者中的 LHON 激活可能会发生。