目的：比较圆锥角膜患者角膜交联(CXL)、等渗(IR)和低渗核黄素(HR)的结果。

方法：回顾性研究，包括29例29眼圆锥角膜患者行角膜交联术，IR组15眼，HR组14眼。参数分析包括(随访1a)：最佳矫正视力(BCVA)，球体和柱体，中央和较薄处角膜厚度，平均和最大角膜曲率(分别为Km和Kmax)，并发症及进展。

结果：观察到两组的BCVA提高：治疗前IR组为0.26±0.57，HR组为0.47±0.72。术后1a，IR组为0.13±0.79，HR组为0.29±1.52，IR组BCVA更高(P=0.018)。术后1mo，两组中央角膜厚度(μm)均减少，但在接下来的数月中增加：术前IR组为497±28 μm，HR组为432±14 μm； 术后1a，IR组为480±31 μm，HR组为424±15 μm。较薄处角膜厚度也是如此，术前IR组为487±29 μm，HR组为410±20 μm； 术后1a，IR组为468±33 μm，HR组为413±13μm。两组中Km和Kmax均降低。每组6眼呈现短暂的混浊，无持续性混浊。

结论：在中央角膜厚度<400μm的患者中，HR的使用似乎是一个有效的替代执行传统CXL的技术。

METHODS: Retrospective study of 29 eyes/keratoconus patients submitted to CXL, 15 eyes with application of IR(IR group)and 14 eyes with application of HR(HR group). The parameters analysed included(1-year follow-up): best corrected visual acuity(BCVA), sphere and cylinder, central and finer pachymetry, mean and maximum keratometry(Km and Kmax respectively), complications and progression.

RESULTS: An increase on the BCVA scale(LogMAR, logarithm of the minimal angle of resolution)was observed in the two groups: 0.26±0.57(IR)and 0.47±0.72(HR)before treatment, and 0.13±0.79(IR)and 0.29±1.52(HR)at the 1y. Only at 1y, the difference was statistically significant(P=0.018, group IR with higher BCVA). The central pachymetry(μm)decreased at 1mo in both groups, and increased in the following months: 497±28 μm(IR)and 432±14 μm(HR)before treatment, and 480±31 μm(IR)and 424±15 μm(HR)to the 1y. The thinner pachymetry(μm)presented the same evolution: 487±29 μm(IR)and 410±20 μm(HR)before treatment, and 468±33 μm(IR)and 413±13μm(HR)at 1y. Km and Kmax decreased in both groups(P>0.05). 6 eyes from each group presented transitory haze. No eye progressed to the 1y.

CONCLUSION:The use of hypotonic riboflavin seems to be a valid alternative for performing the traditional corneal cross-linking technique in eyes with a central corneal thickness of <400 μm.