Reinstein Dan Z, Archer Timothy J, Gobbe Marine
London Vision Clinic, London, United Kingdom.
J Refract Surg. 2009 Jul;25(7):569-77. doi: 10.3928/1081597X-20090610-02.
To determine the 1-year stability of LASIK in corneas with topographic suspect keratoconus confirmed as non-keratoconic by epithelial thickness mapping.
This was a retrospective case/control comparative study. Eyes suspected of keratoconus using criteria based mainly on Atlas (Carl Zeiss Meditec AG) and Orbscan II (Bausch & Lomb) topography were scanned by Artemis very high-frequency digital ultrasound (ArcScan Inc). Keratoconus was confirmed if the epithelial thickness profile showed relative epithelial thinning coincident with an eccentric posterior elevation best-fit sphere apex. Laser in situ keratomileusis was performed in all eyes where keratoconus was excluded by finding relatively thicker epithelium or not finding localized thinning over the topographically suspected cone. Patients were followed for 1 year after LASIK. A control group was generated matched within 0.50 diopter (D) for sphere, cylinder, and spherical equivalent refraction (SEQ) to compare refractive stability.
The average change in SEQ between 3 and 12 months was -0.10+/-0.30 D for the suspect keratoconus group and -0.10+/-0.28 D for controls. No statistically significant difference in shift from 3 months to 12 months in SEQ or cylinder between groups was noted. No statistically significant change in best spectacle-corrected visual acuity between groups was noted, with no eye losing 2 lines and 5% in the suspect keratoconus group and 2% of controls losing 1 line. No cases of ectasia were observed in either group.
Suspect keratoconus, confirmed to be non-keratoconic by epithelial thickness profile criteria demonstrated equal stability to control eyes 1 year after LASIK. Epithelial thickness profiles may enable LASIK to be performed in eyes that would otherwise have been excluded due to topographic suspect keratoconus. Further follow-up is being carried out.
通过上皮厚度测绘确定经地形图检查怀疑圆锥角膜但经确认并非圆锥角膜的角膜行准分子原位角膜磨镶术（LASIK）后的1年稳定性。
这是一项回顾性病例/对照比较研究。主要依据Atlas（卡尔蔡司医疗技术股份公司）和Orbscan II（博士伦公司）地形图标准怀疑为圆锥角膜的眼睛，采用Artemis甚高频数字超声（ArcScan公司）进行扫描。如果上皮厚度剖面图显示相对上皮变薄与偏心后凸最佳拟合球面顶点一致，则确诊为圆锥角膜。在所有通过发现相对较厚上皮或在地形图怀疑圆锥角膜处未发现局部变薄而排除圆锥角膜的眼中进行LASIK手术。LASIK术后对患者进行1年随访。生成一个对照组，使其在球镜、柱镜和等效球镜度（SEQ）方面与研究组相差不超过0.50屈光度（D），以比较屈光稳定性。
可疑圆锥角膜组3至12个月SEQ的平均变化为-0.10±0.30 D，对照组为-0.10±0.28 D。两组之间从3个月到12个月SEQ或柱镜的变化无统计学显著差异。两组之间最佳矫正视力无统计学显著变化，可疑圆锥角膜组无眼视力下降2行，5%的患者视力下降1行，对照组2%的患者视力下降1行。两组均未观察到扩张病例。
经上皮厚度剖面图标准确认并非圆锥角膜的可疑圆锥角膜患者，在LASIK术后1年与对照眼表现出同等的稳定性。上皮厚度剖面图可能使原本因地形图怀疑圆锥角膜而被排除的眼睛能够进行LASIK手术。正在进行进一步随访。
