运用双通道视觉质量分析系统评估角膜交联手术后的客观视觉质量

目的：：采用双通道视觉质量分析系统评估圆锥角膜患者角膜交联手术前后的客观视觉质量。方法：收集2015-01/07患有进展期圆锥角膜而进行紫外光-核黄素角膜交联手术的患者病例资料。利用双通道系统比较手术前和手术后6 mo 患者的客观散射指数( OSI)、对比度视力( VA)、调制传递函数截止频率( MTF cut off)和斯特列尔比( SR)。结果：共收录患者13例16眼。术后6 mo裸眼视力、最佳矫治视力、屈光度、Sim-k平均值与术前相比差异无统计学意义(P>0.05)；眼前节分析仪非侵袭平均泪膜破裂时间( NI Avg-BUT)比术前相比有明显下降，差异有统计学意义(P<0.05)。双通道视觉质量分析系统术后6mo时的MTF cut off、Strehl Ratio、OSI与术前相比差异无统计学意义( P>0.05)；泪膜分析平均 OSI ( tear film analysis mean OSI)比术前明显升高，差异有统计学意义(P<0.05)。结论：角膜交联手术没有使患者的术后视觉质量受到影响，但对术后6 mo的泪膜稳定性有轻度影响，长期结果有待进一步观察。

Evaluation of objective visual quality after corneal cross-linking using double-pass analysis system

AIM: To evaluate the objective visual quality of patients who underwent corneal cross-linking for the keratoconus using double-pass analysis system.

METHODS: Advanced keratoconus patients who underwent UV-riboflavin corneal cross-linking from January to July 2015 were included.The outcomes of their objective scattering index(OSI), predicted visual acuity(VA), the cut-off frequency of modulation transfer function(MTF cut-off), the Strehl ratio(SR)were compared before and 6mo after corneal cross-linking.

RESULTS: A total of 13 patients(16 eyes)were included. There was no statistically significant difference between pre- and 6mo postoperative data in uncorrected visual acuity,best corrected visual acuity,refractions and mean value of Sim-k(P>0.05). Non-invasive average tear film break up time(NIAvg-BUT)detected by the Sirius system decreased after corneal cross-linking(P<0.05). Using double-pass analysis system, no statistically significant change was found in MTF cut off, Strehl Ratio, OSI before and after treatment(P>0.05). Tear Film Analysis Mean OSI increased at 6mo postoperatively(P<0.05).

CONCLUSION: The subjective visual quality isn''t effected by corneal cross-linking. The tear stabilities of patients are influenced by these operations at 6mo postoperatively. More observations on long-term effect are needed to be taken in the future.