方法：研究对象为单纯年龄相关性白内障患者，排除角膜及眼底疾病，主觉验光后充分散瞳，接受OQASII视觉质量分析仪测量客观散射指数(objective scatter index， OSI)及视觉质量指标调制传递函数截止频率(modulation transfer function cut-off， MTF cut-off)值。用Pentacam系统检查测量瞳孔区前皮质、核及后囊下各区域密度。分析所得各项参数结果的相关性，并构造各个区域晶体密度与最佳矫正视力、OSI及MTF cut-off值的多元线性回归方程。

结果：纳入患者69例共108眼。晶状体皮质及核的最大及平均密度均与最佳矫正视力、OSI及MTF cut-off值存在较好的相关性，且与OQAS所测得的OSI及MTF的相关性更大。通过分析所得到的多元线性回归方程，OSI是与密度相关性最大的指标，且最大密度值在各方程中占最大的影响； 对于OSI和MTF，晶体核的最大密度是最重要的影响因素； 同时在MTF和最佳矫正视力的影响中，皮质的混浊也占较大的比例。

结论：晶体的前后皮质及晶体核，晶体任何区域的混浊都影响着视觉质量和视力。晶体核的密度在对OSI和MTF的影响中最大，皮质次之。OQASII视觉质量分析仪可以作为混合性白内障客观分析仪器，其所测得的OSI是对晶体密度改变最敏感的指标，可作为辅助诊断白内障和选择手术时机的重要工具。

METHODS: The patients with age-related cataract were recruited, patients who had any abnormality with cornea or fundus were excluded. Objective scatter index(OSI)and modulation transfer function(MTF)cut-off were acquired by the Optical Quality Analysis System II(OQASII)with dilated pupil after the best corrected visual acuity(BCVA)was obtained. The pupillary regional density of anterior cortex, lens nucleus, posterior cortex was measured via a Pentacam Scheimpflug System(Oculus, Wetzlar, Germany). Correlation analysis was applied to determine the relationship between these parameters. Multiple linear regression relationships were analyzed between the regional lens densities and OSI, MTF, BCVA.

RESULTS:Sixty-nine patients(108 eyes)were studied. Both nuclear and cortical lens density were significantly correlated with the OSI, MTF cut-off and BCVA. The correlation between lens opacities(anterior cortex and nucleus)and OSI/MTF was stronger than that between lens opacities and BCVA. By analyzing multiple linear regressions, OSI had the largest relevance with all regional opacities while maximum density had larger relevance than average density in every parameter. Maximum nuclear density weighted most in both OSI and MTF equations, whereas average cortex density raised weight in MTF and BCVA equations.

CONCLUSION: Any local opacity in the lens, including anterior cortex, nucleus and posterior cortex, could impact both visual quality(VQ)and visual acuity(VA). Nuclear density had the most influence on OSI and MTF, followed by cortical opacity. OQAS II analyzer ought to be provided as an auxiliary pre-surgery tool for mixed cataract with cortical and nuclear opacities since OSI was discovered to be the most sensitive parameter to lens opacities.