Corneal Dystrophy Research Institute, Department of Ophthalmology, College of Medicine, Yonsei University, Seoul, Korea.
Cornea. 2011 Jul;30(7):729-38. doi: 10.1097/ICO.0b013e3182000933.
Granular corneal dystrophy type 2 (GCD2) causes the formation of corneal deposits having 3 different morphological types. We used Fourier domain optical coherence tomography to assess the depths of each type according to the morphology.
A prospective study was performed in 54 eyes of 54 heterozygous patients with GCD2. Corneal deposits of 54 patients with GCD2 were classified into 3 morphological types: type 1, diffuse haze; type 2, granular shape (2 subgroups: type 2a, round granulated and type 2b, round spiculated); and type 3, linear shape (2 subgroups: type 3a, short side branched and type 3b, long side branched). Using Fourier domain optical coherence tomography, we measured the distances from the Bowman layer to the upper surface of the deposits (USBL), to the lower surface of the deposits (LSBL), and the thickness of the deposits (TD). The deposits formed along the flap interface were also examined among 19 patients who had LASIK.
Types 1 and 2 deposits were always adjacent to the Bowman layer; thus the USBLs for each were 0.0 ± 0.0 μm, whereas that of type 3 deposits was 65.4 ± 48.0 μm (P < 0.0001). The LSBL and TD of linear deposits with long side branches (type 3) (313.3 ± 71.4 and 246.2 ± 71.9 μm) were greater than those of type 1 (47.7 ± 10.2 and 47.7 ± 10.2 μm) and type 2 (91.3 ± 39.5 and 91.3 ± 39.5 μm) (P < 0.0001). There were no differences in the measurements between the subgroups type 2a and type 2b or between types 3a and 3b. USBL of the laser in situ keratomileusis group was 54.5 ± 29.8 μm.
The depths of corneal deposits in patients with GCD2 were associated with the morphology of the deposits. The linear deposits were located most deeply in the cornea, followed by granular deposits and diffuse haze moving anteriorly. Several deposits have distinct depths according to the morphological types.
颗粒状角膜营养不良 2 型（GCD2）可导致角膜沉积物形成 3 种不同的形态类型。我们使用频域光相干断层扫描根据形态对每种类型的深度进行评估。
对 54 名 GCD2 杂合子患者的 54 只眼进行前瞻性研究。将 54 名 GCD2 患者的角膜沉积物分为 3 种形态类型：1 型，弥漫性混浊；2 型，颗粒状（2 个亚组：2a 型，圆形颗粒状和 2b 型，圆形刺状）；3 型，线性（2 个亚组：3a 型，短侧分支和 3b 型，长侧分支）。使用频域光相干断层扫描，我们测量了从 Bowman 层到沉积物上表面（USBL）、到沉积物下表面（LSBL）和沉积物厚度（TD）的距离。在 19 名接受 LASIK 治疗的患者中，还检查了沿瓣界面形成的沉积物。
1 型和 2 型沉积物始终与 Bowman 层相邻；因此，它们的 USBL 均为 0.0±0.0μm，而 3 型沉积物的 USBL 为 65.4±48.0μm（P＜0.0001）。长侧分支（3 型）线性沉积物的 LSBL 和 TD（313.3±71.4 和 246.2±71.9μm）大于 1 型（47.7±10.2 和 47.7±10.2μm）和 2 型（91.3±39.5 和 91.3±39.5μm）（P＜0.0001）。2a 型和 2b 型之间以及 3a 型和 3b 型之间的测量值无差异。LASIK 组的 USBL 为 54.5±29.8μm。
GCD2 患者的角膜沉积物深度与沉积物的形态有关。线性沉积物位于角膜最深部，其次是颗粒状沉积物和向前移动的弥漫性混浊。根据形态类型，一些沉积物具有明显的深度差异。
