Jules Stein Eye Institute and Department of Ophthalmology, University of California, Los Angeles, Los Angeles, California 90095-7002, USA.
Am J Ophthalmol. 2010 Dec;150(6):925-31. doi: 10.1016/j.ajo.2010.06.007.
To determine by magnetic resonance imaging (MRI) the prevalence and anatomy of anomalous extraocular muscle (EOM) bands.
Prospective, observational case series.
High-resolution, multipositional, surface coil orbital MRI was performed using T1 or T2 fast spin echo weighting with target fixation control under a prospective protocol in normal adult subjects and a diverse group of strabismic patients between 1996 and 2009. Images demonstrating anomalous EOM bands were analyzed digitally to evaluate their sizes and paths, correlating findings with complete ophthalmic and motility examinations.
Among 118 orthotropic and 453 strabismic subjects, 1 (0.8%) orthotropic and 11 (2.4%) strabismic subjects exhibited unilateral or bilateral orbital bands having MRI signal characteristics identical to EOM. Most bands occurred without other EOM dysplasia and coursed in the retrobulbar space between rectus EOMs such as the medial rectus to lateral rectus, from superior to inferior rectus, or from 1 EOM to the globe. In 2 cases, horizontal bands from the medial rectus to lateral rectus muscles immediately posterior to the globe apparently limited supraduction by collision with the optic nerve. All bands were too deep to be approached via conventional strabismus surgical approaches.
Approximately 2% of humans exhibit on MRI deep orbital bands consistent with supernumerary EOMs. Although band anatomy is nonoculorotary, some bands may cause restrictive strabismus.
通过磁共振成像（MRI）确定异常眼外肌（EOM）带的发生率和解剖结构。
前瞻性观察病例系列研究。
1996 年至 2009 年，在正常成年受试者和各种斜视患者中，使用带有目标注视控制的 T1 或 T2 快速自旋回波加权，根据前瞻性方案进行高分辨率、多体位、表面线圈眶部 MRI。对显示异常 EOM 带的图像进行数字分析，以评估其大小和路径，并将发现与完整的眼科和运动检查结果相关联。
在 118 名正位和 453 名斜视患者中，1 名（0.8%）正位和 11 名（2.4%）斜视患者出现单侧或双侧眶带，其 MRI 信号特征与 EOM 相同。大多数带均无其他 EOM 发育不良，在直肌 EOM 之间的眶后空间中走行，如内直肌至外直肌、从上直肌至下直肌，或从 1 条 EOM 至眼球。在 2 例病例中，眼球后部的内直肌至外直肌水平带明显与视神经碰撞，限制了上转。所有带都太深，无法通过常规斜视手术方法接近。
大约 2%的人在 MRI 上显示与多余 EOM 一致的深部眶带。尽管带的解剖结构是非眼旋转的，但一些带可能导致限制性斜视。
