Akizawa Yasuko, Yasuzumi Kenjiro, Ida Masahiro
Department of Ophthalmology, Tokyo Metropolitan Ebara General Hospital, 4-5-10 Higashi-yukigaya, Oota-ku, Tokyo 145-0065, Japan.
Nippon Ganka Gakkai Zasshi. 2004 Jan;108(1):12-7.
To study the displacement of the eyeball of high myopia in the muscle cone.
Three patients with esotropia with high myopia(myopic esotropia group), seven patients with high myopia without esotropia (high myopia group), and eight controls(control group) were examined. Using magnetic resonance imaging, the outer axial length and the displacement of the posterior portion of the eyeball in the muscle cone were measured. In order to neglect individual differences, the coronal scanning was perpendicular to the orbital axis. The displacement was measured in the plane 2 mm and 4 mm anterior from the globeoptic nerve junction. The distance of the displacement was represented by the distance from the center of the globe to the center of the muscle cone.
The displacement in the plane 4 mm anterior (mean +/- standard deviation) was greater in the order of the myopic esotropia group(1.6 +/- 0.64 mm), the high myopia group(1.2 +/- 0.51 mm), and the control group(0.059 +/- 0.35 mm). The displacement of the eyeball was largest in the myopic esotropia group(p < 0.001). The outer axial length and the distance of the displacement in all cases was correlated significantly(r = 0.93, p < 0.01). Moreover, the eyeballs of the myopic esotropia group and the high myopia group were displaced upwards in the temporal area.
The posterior portion of high myopia was displaced upwards in the temporal area in the muscle cone regardless of the presence or absence of esotropia. The eyeball originally elongates upwards in the temporal area, not towards the weakest part of the muscle cone.
研究高度近视眼球在肌锥内的移位情况。
对3例患有内斜视的高度近视患者（近视性内斜视组）、7例无内斜视的高度近视患者（高度近视组）和8例对照者（对照组）进行检查。使用磁共振成像测量眼球的眼外轴向长度以及眼球后部在肌锥内的移位情况。为忽略个体差异，冠状扫描垂直于眶轴。在眼球视神经交界处前方2mm和4mm的平面测量移位情况。移位距离用眼球中心到肌锥中心的距离表示。
在眼球视神经交界处前方4mm平面的移位（均值±标准差），按大小依次为近视性内斜视组（1.6±0.64mm）、高度近视组（1.2±0.51mm）和对照组（0.059±0.35mm）。眼球移位在近视性内斜视组最大（p<0.001）。所有病例的眼外轴向长度与移位距离均显著相关（r=0.93，p<0.01）。此外，近视性内斜视组和高度近视组的眼球在颞侧区域向上移位。
无论有无内斜视，高度近视的眼球后部在肌锥内的颞侧区域向上移位。眼球原本在颞侧区域向上伸长，而非朝向肌锥最薄弱的部分。
