双通道视觉质量分析系统评价过敏性结膜炎患者的视觉质量

目的　运用双通道视觉质量分析系统（optical quality analysis system，OQASⅡ）评价过敏性结膜炎患者的视觉质量，为临床研究提供相关的数据。方法　选择30例（60眼）过敏性结膜炎患者纳入过敏性结膜炎组；另选取30例（60眼）正常人纳入对照组。获得并分析两组受试者的视力、屈光参数、泪膜破裂时间（break-up time，BUT）以及泪液分泌试验。通过眼前节相干光断层扫描仪记录各组受试者泪河高度、泪河深度以及泪河横截面面积。采用OQAS II记录调制传递函数截止空间频率（modulation transfer function cut off frequency，MTF cutoff）、斯特列尔比（Strehl ratio，SR）、客观散射指数（objective scattering index，OSI）、对比度分别为100%、20%、9%时的 OV值（OV100%、OV20%、OV9%）。比较两组各数据之间的差异性，采用Spearman秩相关分析法分析数据资料间的相关性。结果　过敏性结膜炎组和对照组球镜度、柱镜度、泪液分泌试验、泪河高度、泪河深度、泪河横截面面积各项指标差异均无统计学意义（均为P>0.05）。过敏性结膜炎组的BUT为（8.12±1.91）s，较对照组（10.81±2.53）s小，差异有统计学意义（P<0.01）。过敏性结膜炎组的MTFcutoff、SR、OV100%、OV20%、OV9%值均低于对照组，差异均有统计学意义（均为P<0.05）；OSI值高于对照组，差异有统计学意义（P<0.05）。MTFcutoff、SR、OV100%、OV20%、OV9%值与BUT呈正相关性（均为P<0.01）；OSI 值与BUT呈负相关性（P<0.01）。结论　过敏性结膜炎患者的视觉质量低于正常人群，而这些改变可能与患者泪膜稳定性下降有关。

Evaluation of visual quality in patients with allergic conjunctivitis by double-channel visual quality analysis system

Objective　The aim of the study is to evaluate the visual quality of patients with allergic conjunctivitis by double-pass optical quality analysis system （OQAS II），and provide relevant data for clinical research.Methods　Total 30 patients （60 eyes） with allergic conjunctivitis were taken into the allergic conjunctivitis group；Another 30 patients （60 eyes） of normal people were selected in the control group.The value of visual acuity，refractive parameters，break-up time of tear film （BUT） and Schirmer I test were obtained and analyzed.The height，depth and cross-sectional area of the tear meniscus of each group were recorded by anterior segment optical coherence tomography.OQAS II system was taken to record modulation transfer function cut off frequency （MTF cutoff），Strehl ratio （SR），objective scattering index （OSI） and OQAS value with the contrast at 100%，20% and 9% （OV100%，OV20% and OV9%）.Differences of the parameters were compared between two groups.The correlation between data was analyzed by Spearman rank correlation analysis.Results　There was no significant differences in lens degree，column lens degree，Schirmer I test，tear meniscus height，tear meniscus depth and tear meniscus areabetween allergic conjunctivitis group and control group （all P>0.05）.The BUT in the allergic conjunctivitis group was （8.12±1.91）s，which was smaller than the control group（10.81±2.53）s.The difference was statistically significant （P<0.01）.In the allergic conjunctivitis group，the values of MTF cutoff，SR，OV100%，OV20% and OV9% values were all lower than those in the control group.The differences were statistically significant （all P<0.05）.The value of OSI was higher than that of the control group，and the difference was statistically significant （P<0.05）.The values of MTF cutoff，SR，OV100%，OV20%，OV9% were positively correlated with the value of BUT （all P<0.01）；The value of OSI was negatively correlated with the value of BUT（P<0.01）.Conclusion　The visual quality of allergic conjunctivitis patients is lower than that of normal patients，which may be related to the decreased stability of the tear membrane in the patient．