Vissum/Instituto Oftalmológico de Alicante, Spain.
Ophthalmology. 2011 Jul;118(7):1282-90. doi: 10.1016/j.ophtha.2010.12.012. Epub 2011 Mar 26.
To evaluate the clinical outcomes after implantation of the MyoRing (DIOPTEX GmBH, Linz, Austria) by means of femtosecond laser technology in eyes with corneal ectasia.
Retrospective, consecutive, nonrandomized, case series.
A total of 12 eyes of 11 patients with ages ranging from 17 to 50 years were included. All cases were diagnosed with corneal ectasia according to the standard criteria: 1 case of post-LASIK ectasia and 11 cases of keratoconus. All cases presented with reduced best spectacle-corrected visual acuity, contact lens intolerance or discomfort, and central corneal thickness of more than 350 μm.
MyoRing inserts of 280 μm in thickness and 5 mm in diameter were implanted in all cases into an intrastromal corneal pocket created by means of femtosecond technology. Visual, refractive, corneal topography, and pachymetric changes were evaluated during a 6-month follow-up. In addition, corneal biomechanical changes were evaluated by means of the Ocular Response Analyzer (Reichert, Buffalo, NY).
Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, keratometry, corneal asphericity, corneal higher-order aberrations, pachymetry, corneal hysteresis (CH), and corneal resistance factor (CRF).
A significant improvement in UDVA was observed 1 week after surgery (P=0.001), which was consistent with the significant reduction in sphere (P=0.002) and cylinder (P=0.004). No significant changes were detected in these parameters afterward (P ≥ 0.263). Furthermore, a significant corneal flattening of a mean value of 8.03 diopters (D) was found (P=0.005). This keratometric change was correlated with the magnitude of corneal coma-like aberrations (r=0.830, P=0.003) and the CRF (r=-0.782, P=0.008). In regard to aberrometry, a statistically significant increase in primary spherical aberration was found 1 month after surgery (P=0.001). In addition, a significant reduction in higher-order corneal aberrations was found 3 to 6 months after surgery (P=0.027). Significant corneal thickening was also observed postoperatively in the central, nasal, and temporal areas (P ≤ 0.013). No statistically significant changes were detected (P ≥ 0.176) in corneal biomechanics. Explantation was performed in a very advanced keratoconus because of the extremely poor visual outcome.
MyoRing implantation using femtosecond technology in keratoconus allows successful corneal modeling, although the use of large diameters is advisable.
评估应用飞秒激光技术在角膜扩张症患者中植入 MyoRing（DIOPTEX GmBH，林茨，奥地利）的临床效果。
回顾性、连续、非随机、病例系列研究。
共纳入 11 例 12 只眼患者，年龄 17 至 50 岁。所有病例均根据标准标准诊断为角膜扩张症：1 例 LASIK 后扩张，11 例为圆锥角膜。所有病例均表现为最佳矫正视力下降、隐形眼镜不耐受或不适，以及中央角膜厚度超过 350μm。
所有病例均采用飞秒技术在角膜内创建一个间质角膜袋，植入厚度为 280μm、直径为 5mm 的 MyoRing 植入物。在 6 个月的随访期间评估视力、屈光、角膜地形图和角膜测厚。此外，还通过眼反应分析仪（Reichert，Buffalo，NY）评估角膜生物力学变化。
未矫正距离视力（UDVA）、矫正距离视力（CDVA）、角膜曲率、角膜不规则性、角膜高阶像差、角膜测厚、角膜滞后（CH）和角膜阻力因子（CRF）。
术后 1 周 UDVA 显著改善（P=0.001），与球镜（P=0.002）和柱镜（P=0.004）显著减少一致。此后，这些参数没有发现明显变化（P≥0.263）。此外，发现角膜平均平坦度为 8.03 屈光度（D）（P=0.005）。这种角膜屈光度的变化与角膜彗差样像差的大小（r=0.830，P=0.003）和 CRF（r=-0.782，P=0.008）相关。在像差方面，术后 1 个月发现初级球差有统计学意义的增加（P=0.001）。此外，术后 3 至 6 个月发现高阶角膜像差显著减少（P=0.027）。术后中央、鼻侧和颞侧角膜也明显增厚（P≤0.013）。角膜生物力学无统计学意义的变化（P≥0.176）。
在圆锥角膜中应用飞秒技术植入 MyoRing 可成功进行角膜塑形，尽管建议使用较大直径。
