Kilicarslan R, Alkan A, Ilhan M M, Yetis H, Aralasmak A, Tasan E
1 Department of Radiology, Bezmialem Vakif University School of Medicine, Istanbul, Turkey.
Br J Radiol. 2015 Mar;88(1047):20140677. doi: 10.1259/bjr.20140677. Epub 2014 Dec 19.
To evaluate involvement of the extraocular muscle (EOM) using diffusion-weighted imaging (DWI), to determine whether there is correlation with conventional orbital MRI and apparent diffusion coefficient (ADC) values in patients with Graves' ophthalmopathy (GO).
35 patients known clinically with GO and 21 healthy controls were studied. Patients were assessed with clinical activity scores. All subjects underwent conventional MRI and DWI study. Involvement of the EOM was evaluated. The patients were classified as involved or uninvolved on orbital MRI and their ADC values in DWI compared.
There was significant difference in the mean ADC value of all the EOMs in patients vs controls. The ADC values of all the EOMs were higher in patients. There were significant differences in ADC values between uninvolved muscles on conventional MRI and controls for the MR, SR and LR. There was no significant difference in ADC value between the two groups when considering the IR. ADC values of medial, lateral and superior rectus muscles were increased.
Increased ADC values of the EOM in patients with GO suggest that EOM damage begins at a very early stage before being detected on routine orbital MRI. The routine MRI with DWI sequence will be a useful adjunct in the selection of a group of patients most likely to benefit from early treatment.
This study can help to evaluate the involvement of GO in early period with MRI added DWI.
使用扩散加权成像（DWI）评估眼外肌（EOM）的受累情况，以确定在格雷夫斯眼病（GO）患者中其与传统眼眶磁共振成像（MRI）及表观扩散系数（ADC）值是否存在相关性。
对35例临床诊断为GO的患者和21例健康对照者进行研究。对患者进行临床活动评分评估。所有受试者均接受传统MRI和DWI检查。评估眼外肌的受累情况。根据眼眶MRI将患者分为受累或未受累，并比较其DWI中的ADC值。
患者与对照组所有眼外肌的平均ADC值存在显著差异。患者所有眼外肌的ADC值更高。对于上直肌（MR）、上斜肌（SR）和外直肌（LR），传统MRI上未受累肌肉与对照组之间的ADC值存在显著差异。考虑下直肌（IR）时，两组间ADC值无显著差异。内直肌、外直肌和上直肌的ADC值升高。
GO患者眼外肌的ADC值升高表明，在常规眼眶MRI检测到之前，眼外肌损伤在很早阶段就已开始。采用DWI序列的常规MRI将有助于选择最有可能从早期治疗中获益的一组患者。
本研究有助于通过添加DWI的MRI评估GO的早期受累情况。
