Nishida Y, Hayashi O, Nishida E, Murata T, Aoki Y, Inatomi A, Kani K, Mabuchi N, Furutani Y
Department of Ophthalmology, Shiga University of Medical Science, Otsu, Japan.
Nippon Ganka Gakkai Zasshi. 1993 Jul;97(7):827-33.
The volume of the horizontal extraocular muscles of 11 normal adults and three patients with ophthalmoplegia was measured using magnetic resonance imaging (MRI). The MRI examinations were carried out with a Signa Advantage, 1.5 tesla superconductive magnetic system manufactured by General Electric. This method employs the spin echo technique with a 3.0 mm gapless slice, a 350 ms. repetition time, and a 17.0 ms. echo time. The MRI films were projected and magnified on Kent paper using an overhead projector. Then the shapes of the horizontal extraocular muscles were traced. The volume of the muscles was measured as the total weight of Kent papers which were cut out from muscle shapes in all the slices. The average volume of the normal medial and lateral rectus muscles was 690 +/- 87 mm3 and 734 +/- 77 mm3, respectively. Two cases with peripheral nerve palsy showed typical atrophy of the paretic muscles. A case with orbital myositis showed typical hypertrophy of the inflamed muscles. This measurement may prove useful in the analysis and evaluation of extraocular muscles, especially in ophthalmoplegia.
使用磁共振成像（MRI）测量了11名正常成年人和3名眼肌麻痹患者的水平眼外肌体积。MRI检查是使用通用电气公司生产的1.5特斯拉超导磁体Signa Advantage进行的。该方法采用自旋回波技术，层厚3.0毫米无间隙，重复时间350毫秒，回波时间17.0毫秒。使用投影仪将MRI胶片投影并放大在绘图纸上。然后描绘水平眼外肌的形状。肌肉体积通过从所有切片中的肌肉形状切下的绘图纸的总重量来测量。正常内直肌和外直肌的平均体积分别为690±87立方毫米和734±77立方毫米。2例周围神经麻痹患者显示出患侧肌肉典型的萎缩。1例眼眶肌炎患者显示出炎症肌肉典型的肥大。这种测量方法可能对眼外肌的分析和评估有用，尤其是在眼肌麻痹方面。
