期刊
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
卷 58, 期 10, 页码 4114-4125出版社
ASSOC RESEARCH VISION OPHTHALMOLOGY INC
DOI: 10.1167/iovs.17-22093
关键词
biomechanics; orbit; extraocular muscle; magnetic resonance imaging
资金
- US Public Health Service, National Eye Institute (Bethesda, MD, USA) [EY008313, EY000331]
- Research to Prevent Blindness (New York, NY, USA)
PURPOSE. We used magnetic resonance imaging (MRI) to ascertain effects of optic nerve (ON) traction in adduction, a phenomenon proposed as neuropathic in primary open-angle glaucoma (POAG). METHODS. Seventeen patients with POAG and maximal IOP <= 20 mm Hg, and 31 controls underwent MRI in central gaze and 208 to 308 abduction and adduction. Optic nerve and sheath area centroids permitted computation of midorbital lengths versus minimum paths. RESULTS. Average mean deviation (6SEM) was -8.2 6 1.2 dB in the 15 patients with POAG having interpretable perimetry. In central gaze, ON path length in POAG was significantly more redundant (104.5 +/- 0.4% of geometric minimum) than in controls (102.9 +/- 0.4%, P = 2.96 x 10(-4)). In both groups the ON became significantly straighter in adduction (28.6 +/- 0.88 in POAG, 26.8 +/- 1.18 in controls) than central gaze and abduction. In adduction, the ON in POAG straightened to 102.0% +/- 0.2% of minimum path length versus 104.5% +/- 0.4% in central gaze (P = 5.7 x 10(-7)), compared with controls who straightened to 101.6% +/- 0.1% from 102.9% +/- 0.3% in central gaze (P = 8.7 x 10(-6)); and globes retracted 0.73 +/- 0.09 mm in POAG, but only 0.07 +/- 0.08 mm in controls (P = 8.8 x 10(-7)).Both effects were confirmed in age-matched controls, and remained significant after correction for significant effects of age and axial globe length (P = 0.005). CONCLUSIONS. Although tethering and elongation of ON and sheath are normal in adduction, adduction is associated with abnormally great globe retraction in POAG without elevated IOP. Traction in adduction may cause mechanical overloading of the ON head and peripapillary sclera, thus contributing to or resulting from the optic neuropathy of glaucoma independent of IOP.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据