中文摘要：

目的探讨定量测量TAO患者眼外肌横截面积的可行性，评价其临床意义，根据眼外肌情况讨论TAO亚型的分类。方法回顾性分析2011年1月至2012年5月在上海长征医院眼科就诊的20例正常对照者、42例TAO患者眼眶CT冠状位平扫图像，利用autoCAD软件测量各眼外肌最粗处横截面积。结果TAO组下直肌、外直肌、提上睑肌上直肌复合体、内直肌以及眼外肌总横截面积均〉正常对照组，差异有统计学意义（P=0．033，P〈0．05）。眼外肌总横截面积与CAS评分呈正相关差异有统计学意义（，=0．791，P〈0．05），与矫正视力呈负相关差异有统计学意义（r=-0．658，P〈O．05）。根据眼外肌总横截面积和眼球突出度，可将TAO分为4种亚型：I型0例，眶脂肪和眼外肌均不增多；Ⅱ型9例（21．4％），眶脂肪增多为主；II型10例（23．8％），眼外肌增粗为主；1V型23例（54．8％），眶脂肪和眼外肌均增多。结论TAO患者眼眶CT冠状位平扫定量测量眼外肌横截面积，能够准确反映眼外肌增粗的情况，为评估TAO患者的活动性、区分TAO亚型提供了可靠依据。

英文摘要：

Objective To analyzetheextraocular muscle coronal area（EMA） in thyroid associated oph- thalmopathy （TAO） and describe different TAO subtypes.MethodsA retrospective study.By using commer- cial software with a segmentation technique, EMA in 42 patients with TAO and 20 control subjects were calculated from computed tomography （CT） scan.Results The coronal area of inferiorrectus, lateral rectus,superior rectus, medial rectus and total EMA were significantly larger in patients with TAO than the control subjects （P =0.033, P 〈0.001, P 〈0.05）. Clinical Activity Score（CAS） and corrected visual acuity were significantly correlated to the total EMA in TAO patients. Four subtypes of TAO could be distinguished： Group I, no orbit fat（OF） and extraocular muscles（EM） increase; Group Ⅱ, only OF in- crease （21.4%）; Group Ⅲ,only EM increase （23.8%）; Group IV,both OFand EM increase （54.8%）. Con- clusions Calculating EMA of CT in TAO patients should be taken into consideration. Total EMA is cor- related to the CAS and could distinguish the subtypes of TAO.