黄斑部病变的局部视网膜电图和图形视觉诱发电位

Local electroretinogram and pattern visual evoked potential in maculopathies

目的观察黄斑病变局部视网膜电图（ｌｏｃａｌｅｌｅｃｔｒｏｒｅｔｉｎｏｇｒａｍ，ＬＥＲＧ）和图形视觉诱发电位（ｐａｔｅｒｎｖｉｓｕａｌｅｖｏｋｅｄｐｏｔｅｎｔｉａｌ，ＰＶＥＰ）的变化，评价二者的临床应用价值。方法对２７例（５４只眼）正常人进行黄斑部视角５°、１０°和１５°ＬＥＲＧ测定，并对２５例（３５只眼）黄斑病变患者进行ＬＥＲＧ和ＰＶＥＰ的测定。结果黄斑病变患者５°、１０°和１５°ＬＥＲＧ的ａ、ｂ波振幅均值较正常对照组均有显著性降低（Ｐ＜０．０１），３６．５′、７３′及１４６′ＰＶＥＰ的Ｐ１波潜伏期及振幅均值分别较正常对照组明显延长和降低（Ｐ＜０．０１）。在ＬＥＲＧ（１５°）与ＰＶＥＰ（１４．８°×１９．０°）刺激野相近的条件下，黄斑病变ＬＥＲＧ异常率为６２．２％、ＰＶＥＰ的异常率分别为４８．５％（１４６′）、５４．５％（７３′）及４８．５％（３６．５′），ＬＥＲＧ和ＰＶＥＰ的异常率差异均无显著性（Ｐ＞０．０５）。结论ＬＥＲＧ与ＰＶＥＰ的异常率相接近。由于ＬＥＲＧ不受视路功能的影响。

Objectives To observe the changes of local electroretinogram (LERG) and pattern visual evoked potential (PVEP) in maculopathies and to evaluate the value of both LERG and PVEP in clinical application. Methods LERGs at 5°、10° and 15° macular region were recorded from 27 normal subjects (54 eyes). The LERG and PVEP were recorded from 25 patients( 35 eyes) with maculopathies. Results In the patients with maculopathies, the amplitudes of LERG a wave and b wave at 5 °、10° and 15° macular region were significantly lowered ( P <0.01), the mean value of P 1 latency was prolonged and that of N 1～P 1 amplitude of VEP was lowered at 36.5′,73′ and 146′ in the comparison with the control group. In approximately the same stimulated area (15° LERG and 14 8°×19.0° PVEP), the abnormal rate of LERG was 62.2%, and the abnormal rates of PVEPs were 48.5% (146′),54 5%(73′) and 48.5% (36.5′) respectively, no significant difference in the abnormal rate between LERG and each value of PVEP ( P >0.05) being found. Conclusion The abnormal rates of LERG and PVEP in maculopathies are close. Because LERG is not influenced by visual pathway diseases and visual acuity, LERG is more effective than PVEP and is a direct way in measuring macular function.