Schallhorn Julie M, Tang Maolong, Li Yan, Louie Derek J, Chamberlain Winston, Huang David
From the Department of Ophthalmology (Schallhorn) and the Francis I. Proctor Foundation (Schallhorn), University of San Francisco, San Francisco, California, and the Center for Ophthalmic Optics and Lasers (Tang, Li, Louie, Chamberlain, Huang), Casey Eye Institute, and Department of Ophthalmology, Oregon Health & Science University, Portland, Oregon, USA.
From the Department of Ophthalmology (Schallhorn) and the Francis I. Proctor Foundation (Schallhorn), University of San Francisco, San Francisco, California, and the Center for Ophthalmic Optics and Lasers (Tang, Li, Louie, Chamberlain, Huang), Casey Eye Institute, and Department of Ophthalmology, Oregon Health & Science University, Portland, Oregon, USA.
J Cataract Refract Surg. 2017 Jan;43(1):60-66. doi: 10.1016/j.jcrs.2016.10.019.
To distinguish between corneal ectasia and contact lens-related warpage by characteristic patterns on corneal topography and optical coherence tomography (OCT) epithelial thickness maps.
Casey Eye Institute, Portland, Oregon, USA.
Prospective and retrospective case series.
Axial and mean power maps were obtained on corneal topography systems. Epithelial thickness maps were generated using RTVue OCT. A sector divider was applied to all maps. The locations of the minimum epithelial thickness, maximum epithelial thickness, maximum axial power, and maximum mean power were determined based on sector averages. Agreement was defined as the extremums occurring in the same or adjacent sectors.
Twenty-one eyes with keratoconus, 6 eyes with forme fruste keratoconus (better eye of asymmetric keratoconus), and 15 eyes with contact lens-related warpage were identified. The keratoconus and forme fruste keratoconus eyes had coincident topographic steepening with epithelial thinning. The locations of minimum epithelial thickness and maximum axial power agreed in 90% of the keratoconic eyes, while the minimum epithelial thickness and maximum mean power agreed in 95% of them. Conversely, the warpage eyes had coincident topographic steepening with epithelial thickening and normal pachymetry maps. The locations of maximum epithelial thickness and maximum axial power agreed in 93% of the warpage eyes, while the maximum epithelial thickness and maximum mean power agreed in all warpage eyes.
Results show that epithelial thickness maps and corneal topographic maps are powerful synergistic tools in evaluating eyes with abnormal topography and can help differentiate between keratoconus and nonectatic conditions.
通过角膜地形图和光学相干断层扫描（OCT）上皮厚度图上的特征性模式，区分角膜扩张和与隐形眼镜相关的角膜变形。
美国俄勒冈州波特兰市凯西眼科研究所。
前瞻性和回顾性病例系列。
在角膜地形图系统上获取轴向和平均屈光力图。使用RTVue OCT生成上皮厚度图。对所有地图应用扇形划分器。根据扇形平均值确定最小上皮厚度、最大上皮厚度、最大轴向屈光力和最大平均屈光力的位置。一致性定义为极值出现在相同或相邻扇形中。
确定了21只圆锥角膜眼、6只顿挫型圆锥角膜眼（不对称圆锥角膜的较好眼）和15只与隐形眼镜相关的角膜变形眼。圆锥角膜和顿挫型圆锥角膜眼的地形变陡与上皮变薄同时出现。90%的圆锥角膜眼中最小上皮厚度和最大轴向屈光力的位置一致，95%的圆锥角膜眼中最小上皮厚度和最大平均屈光力的位置一致。相反，角膜变形眼的地形变陡与上皮增厚同时出现，且角膜厚度测量图正常。93%的角膜变形眼中最大上皮厚度和最大轴向屈光力的位置一致，所有角膜变形眼中最大上皮厚度和最大平均屈光力的位置一致。
结果表明，上皮厚度图和角膜地形图是评估地形异常眼睛的强大协同工具，有助于区分圆锥角膜和非扩张性疾病。
