Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seodaemun-ku, Seoul, Korea.
Eye Contact Lens. 2010 Sep;36(5):296-9. doi: 10.1097/ICL.0b013e3181ef0da0.
To review the literature about clinical findings and treatments of granular corneal dystrophy type 2 (GCD2).
Various literatures on clinical findings, exacerbations after refractive corneal surgery, and treatment modalities of GCD2 were reviewed.
GCD2 is an autosomal dominant disease. Mutation of transforming growth factor beta-induced gene, TGFBI, or keratoepithelin gene in human chromosome 5 (5q31) is the key pathogenic process in patient with GCD2. Corneal trauma activates TGFBI and then it overproduces transforming growth factor beta-induced gene protein (TGFBIp), which is main component of the corneal opacity. Refractive corneal surgery is a popular procedure to correct refractive error worldwide. However, several cases about exacerbation of GCD2 after corneal refractive surgery such as photorefractive keratectomy, laser in situ keratomileusis, and laser epithelial keratomileusis have been reported. The opacities deteriorate patient's best-corrected visual acuity. Recurrence-free interval varies many factors such as the type of procedure the patient had received and the genotype of the patient. To treat the opacities in GCD2, phototherapeutic keratectomy, lamellar keratoplasty, deep lamellar keratoplasty, and penetrating keratoplasty (PKP) were used. However, the recurrence is still an unsolved problem.
Perfect treatment of exacerbation after corneal surface ablation does not exist until now. To prevent exacerbation, refractive surgeons must do a careful preoperative examination of candidates in refractive surgeries.
综述 2 型颗粒状角膜营养不良（GCD2）的临床特征和治疗方法的文献。
综述了 GCD2 的临床特征、屈光性角膜手术后的恶化以及治疗方法的各种文献。
GCD2 是一种常染色体显性遗传疾病。人类染色体 5（5q31）上转化生长因子β诱导基因 TGFBI 或角膜上皮素基因的突变是 GCD2 患者的关键致病过程。角膜创伤激活 TGFBI，然后过度产生转化生长因子β诱导基因蛋白（TGFBIp），这是角膜混浊的主要成分。屈光性角膜手术是全球矫正屈光不正的一种流行方法。然而，已经报道了几例屈光性角膜手术后 GCD2 恶化的病例，如光折射性角膜切削术、准分子激光原位角膜磨镶术和激光上皮下角膜磨镶术。混浊会降低患者的最佳矫正视力。无复发间隔受多种因素影响，如患者接受的手术类型和患者的基因型。为了治疗 GCD2 中的混浊，使用光疗性角膜切削术、板层角膜移植术、深层板层角膜移植术和穿透性角膜移植术（PKP）。然而，复发仍然是一个未解决的问题。
直到现在，还没有完美的方法来治疗角膜表面消融术后的恶化。为了预防恶化，屈光外科医生在屈光手术前必须对候选者进行仔细的术前检查。
