目的：探讨儿童眼肌型重症肌无力(OMG)患儿发生眼肌麻痹的相关因素。方法：回顾性分析2011-11/2020-05期间就诊于我院的203例儿童OMG患儿，将其分为眼肌麻痹组97例和非眼肌麻痹组106例，对两组患儿的临床资料进行单因素统计分析，对有统计学差异的指标进一步行多因素回归分析。结果：纳入的203例儿童OMG患儿发生眼肌麻痹者97例(47.8%)，69例(71.1%)表现为斜视，其次为歪头视物(18例，18.6%)。97例患儿中单眼79例(81.4%)，单条眼外肌受累53例(54.6%)，其中内直肌19例(35.8%)。眼肌麻痹组和非眼肌麻痹组患儿年龄，血清免疫球蛋白M(IgM)，血清游离三碘甲状腺原氨酸(FT3)，血清甲状腺球蛋白(TG)，采用激素联合治疗(72.2% vs 38.7%)均有统计学意义(P<0.05)。血清FT3水平(OR=2.006，95%CI：1.233～3.263)和采用激素联合治疗(OR=4.328，95%CI：1.936～9.677)是影响儿童OMG患儿发生眼肌麻痹的相关因素。结论：儿童OMG患儿发生眼肌麻痹较常见，单眼多发，内直肌最易受累，较少出现复视。血清FT3可作为评估儿童OMG患儿发生眼肌麻痹的重要免疫指标。

AIM: To investigate the related-factors analysis of extra-ocular muscle paralysis in pediatric ocular myasthenia gravis(OMG). METHODS: A retrospective, observational cohort study was performed of 203 pediatric patients diagnosed with OMG between Nov.2011 and May 2020 at Wuhan Children's Hospital. Data on clinical features and laboratory indicators of children with OMG were statistically analyzed between extra-ocular muscle paralysis group and non-extra-ocular muscle paralysis group, which were classified by pediatric ophthalmologists based on ocular manifestations. The Logistic regression analysis was performed immediately after that to determine the independent factors. RESULTS: Totally 203 pediatric OMG, 97(47.8%)had extra-ocular muscle paralysis with various clinical features including strabismus(n=69, 71.1%), torticollis(n=18, 18.6%). Among the 97 children, 79(81.4%)patients were presented with monocular involvement, of which 53(54.6%)had single extra-ocular muscle paralysis. The most common was medial rectus muscle(n=19, 35.8%). Between extra-ocular muscle paralysis group and non-extra-ocular muscle paralysis group, there were statistically significant difference(P<0.05)in age, serum immunoglobulin M(IgM), serum free triiodothyronine(FT3), serum thyroglobulin, and glucocorticoid combination pyridostigmine bromide therapy(72.2% vs 38.7%). Furthermore, the level of FT3(OR=2.006, 95%CI: 1.233-3.263)and glucocorticoid combined treatment(OR=4.328, 95%CI: 1.936-9.677)were the related-factors affecting the extra-ocular muscle paralysis of children with ocular myasthenia gravis. CONCLUSION: Extra-ocular muscle paralysis was the common ocular manifestation in pediatric OMG. Monocular involvement was more common than binocular involvement especially the medial rectus muscle, while diplopia was rare. The level of FT3 can be considered as an important immune indicator to evaluate extra-ocular muscle paralysis in children with ocular myasthenia gravis.