特发性视神经炎患者视力恢复后对比敏感度检测

Preliminary report of contrast sensitivity in idiopathic optic neuritis patients after recovery

目的探讨特发性视神经炎患者对比敏感度水平的变化规律。方法病例对照研究。收集临床确诊的特发性视神经炎患者22例，经过不同时间的治疗视力恢复正常，神经系统MRI检查无异常。同时纳入24名健康人作为对照。采用OPTEC6500型对比敏感度测试仪检测患眼5个空间频率的对比敏感度值，并进行统计学分析。组间相同频率间比较采用t检验或“检验，组内不同空间频率间比较采用方差分析或日检验，分析与年龄、病程和性别的关系时采用简单直线相关方法，并总结两组走行趋势。结果特发性视神经炎组与对照组远、近距离对比敏感度值最大均出现在6．0c／d，分别为70．27±40．44、53．32±29．50及78．86±36．37、109．39±44．98。最小均出现在18．0c／d，分别为8．27±6．11、12．09±8．57和15．67±9．02、22．22±14．56。视神经炎组在远、近距离的5个空间频率上的对比敏感度与对照组比较差异有统计学意义[空间频率从1．5至18．0e／d，远距离t（u或t’）值分别为4．19，5．59，3．06，2．50，3．13；P值分别为0．00，0．00，0．00，0．01，0．00。近距离t（u或t’）值分别为3．54，3．98，2．72，3．20，3．39；P值分别为0．00，0．00，0．01，0．00，0．00]，其水平与病程无关。两组内远、近距离不同空间频率对比敏感度值比较，多数频率间的差异有统计学意义（视神经炎组远、近距离日值分别为52．38和64．96，对照组分别为64．77和60．53，P值皆〈0．01）。最大H值出现在视神经炎组的近距离。H值最大为64．96，出现在视神经炎组的近距离。特发性视神经炎组和对照组部分频率自身远、近距离对比敏感度值间的差异有统计学意义（空间频率由低到高，视神经炎组，值分别为6．36，0．03，2．52，1．53，2．90；P值分别为0．02，0．87，0．12，0．22，0．10。对照组F值分别为5．31，5．69，6．06，0．61，3．14；P值分别为0．03，0．02，0．02，0．44，0．08）。结论具有正常视力的视神经炎患者各频率对比敏感度值显著下降，对比敏感度可以作为评价特发性视神经炎后视觉质量的重要手段。

Objective To explore the changes of contrast sensitivity （CS） in patients recovered from idiopathic optic neuritis （ION）. Methods It was a case-control study. We screened 22 idiopathic optic neuritis patients who underwent treatment and obtained normal visual acuity. No nervous system abnormalities were found in MRI scan. Twenty four healthy individuals were enrolled as the control group. OPTEC 6500 contrast sensitivity tester was used to examine near- and far-distance CS values on 1, 5, 3. 0, 6. 0, 12 and 18 cycles/degree （c/d）, separately. T-test or u-test was used to compare the mean of CS values between these two groups. ANOVA or H-test was adopted on CS values at the different frequencies in each group. Simple linear correlation was used to analyze the correlation between CS values and age, duration and gender, separately. Results The maximum CS values in both far- and near-distance appeared in 6. 0 c/d in these two groups were 70. 27 ±40. 44, 53.32 ±29. 50, 78. 86±36. 37 and 109. 39 ±44. 98, respectively. The minimum CS values in both far- and near-distance appeared in 18 c/d in these two groups were 8.27 ±6. 11, 12. 09 ±8.57, 15.67±9. 02 and 22. 22 ±14. 56, respectively. Far- and near-distance CS values in ION group and control group had very significant differences at these five spatial frequencies （From 1.5 to 18.0 c/d,the test values on far-distance were 4.19,5.59,3.06,2.50,3.13, P values were 0. 00,0.00,0.00,0.01,0.00. The test values on near-distance were 3.54,3.98,2.72,3.20,3.39, P values were 0.00,0.00,0.01,0.00,0.00）. CS values had no relation to the duration of ION. Significant difference in CS values existed on most frequencies（ In far- and near-distance, H values in ION group were 52.38 and 64. 96, in control group were 64.77 and 60.53, P values were both less than 0.01 ）. The maximum H value appeared on near-distance in ION group. The maximum H value was 64. 96 of near- distance in ION group. Far- and near-distance CS values in ION group itseff and control group itself had very significant differences at these 5 spatial frequencies （ From low to high frequencies, F values were 6.36, 0. 03,2.52,1.53,2.90; P values were 0. 02,0. 87,0. 12,0.22,0. 10 in ION group. In control group, F values were 5.31,5.69,6.06,0.61,3. 14;P values were 0. 03,0. 02,0. 02,0. 44,0. 08 respectively）. Conclusions CS values at different frequencies in ION patients with normal visual acuity descend significantly. Contrast sensitivity examination can be an important technique to evaluate vision quality in patients after ION.