Lee Brandon W, Jurkunas Ula V, Harissi-Dagher Mona, Poothullil Antony M, Tobaigy Faisal M, Azar Dimitri T
Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA.
Am J Ophthalmol. 2007 Jul;144(1):154-156. doi: 10.1016/j.ajo.2007.02.032.
To identify clinical findings associated with claw-shaped patterns on corneal topography.
Retrospective, observational case series.
Forty eyes (26 patients) with classic claw-shaped patterns on corneal topography were identified from 3,993 Orbscan II records. They were subclassified into three groups: Group 1 (pellucid marginal degeneration [PMD] or PMD suspect); group 2 (keratoconus or keratoconus suspect); and group 3 (ectasia). The refractive and topographic indices of groups 1 and 2 were compared.
There were nine eyes (six patients) in group 1, 27 eyes (18 patients) in group 2, and four eyes (two patients) in group 3. The mean radii of maximal anterior (2.96 mm) and posterior (3.06 mm) elevation in group 1 were significantly greater than those of group 2 (1.89 mm; P = .018 and 1.72 mm; P = .022, respectively).
The claw-shaped pattern on corneal topography is not diagnostic of PMD; it is also seen in keratoconus.
确定与角膜地形图上爪形图案相关的临床特征。
回顾性观察病例系列。
从3993份Orbscan II记录中识别出40只眼（26例患者）角膜地形图上有典型爪形图案。它们被分为三组：第1组（透明边缘变性[PMD]或疑似PMD）；第2组（圆锥角膜或疑似圆锥角膜）；第3组（扩张）。比较第1组和第2组的屈光和地形学指标。
第1组有9只眼（6例患者），第2组有27只眼（18例患者），第3组有4只眼（2例患者）。第1组最大前凸（2.96mm）和后凸（3.06mm）的平均半径显著大于第2组（分别为1.89mm；P = 0.018和1.72mm；P = 0.022）。
角膜地形图上的爪形图案不能诊断PMD；在圆锥角膜中也可见。
