刺激条件对扫描图像翻转诱发电位视力的影响  

Effects of stimulating actors on the sweep pattern visual evoked response acuity

作　　者：朱捷[1] 杨冠[1] 

机构地区：[1]上海交通大学附属第六医院眼科,上海200233

出　　处：《中国实用眼科杂志》2005年第2期155-158,共4页Chinese Journal of Practical Ophthalmology

摘　　要：目的　研究时间频率和空间频率对扫描图像翻转诱发电位视力准确度的影响。方法　比较 10例 2 0眼正常志愿者SPVER视力和对数视力表视力。在SPVER视力的测定中用 7个不同空间频率的光栅条纹连续扫描 ,所得的数据经离散傅立叶分析后 ,获得振幅 -空间频率曲线 ,并通过外推法估计其视力。诱发电位测定的时间频率分别为 8、 12、 16、 2 0、 2 4Hz ,根据测试距离来调整空间频率。结果　与视力表视力比较各时间频率测定的SPVER视力有良好的相关r =0 87～ 0 5 ,各空间频率间测定的视力有良好的相关性r=0 72～ 0 96。三种不同空间频率测试的SPVER视力和视力表视力比较在低视力段无差异在高视力段所设空间频率越高结果越接近视力表视力。结论　SPVEP视力与视力表视力有良好的相关性。但为使测定的结果更准确可根据条件选取相应的时间和空间频率。Objective To investigate the effect of spatial and temporal frequency on the Sweep pattern visual evoked response acuity(SPVER-A).Methods SPVER-A and optotype visual acuity were compared in 10 volunteers(20eyes).For SPVER-A,7-squared vertical gratings were presented as stimuli continuously.The responses were averaged and displayed through the discrete Fourier transform on the monitor display.The SPVER acuity was determined by extrapolating the SPVER amplitude-spatial frequency function to baseline.The Temporal Frequencies were 8,12,16,20,24Hz.The Spatial Frequency was adjusted by the distance of the measurement.Results The correlation range between the SPVER-A and optotype visual acuity in these 5 Temporal Frequencies were 0 87 to 0 5.The correlation among these Temporal Frequencies were 0 72 to 0 96.By three Spatial Frequencies,there was no statistic different in lower visual range and during the higher range the SPVER-A was much better while used higher Spatial Frequencies.Conclusions SPVER-A has a good correlation to optotype acuity.To choice a suitable Temporal and Spatial Frequencies can make estimating vision effectively.

关 键 词：对数视力表 诱发电位 空间频率 刺激 相关性 近视力 正常 条件 结论 翻转 

分 类 号：R778[医药卫生—眼科] R770[医药卫生—临床医学]