Weleber R G
Oregon Health Sciences University, Casey Eye Institute, Portland 97201-4197, USA.
Eye (Lond). 1998;12 ( Pt 3b):580-90. doi: 10.1038/eye.1998.148.
The neuronal ceroid lipofuscinoses (NCL) are neurodegenerative disorders with psychomotor deterioration, seizures, visual failure and premature death, all associated with abnormal storage of lipoproteins within lysosomes. The most common forms of NCL are an infantile form (INCL, CLN1), a late infantile form (LINCL, CLN2) and a juvenile onset form (JNCL, CLN3). The electroretinogram (ERG) is abnormal early in all three of these forms and eventually is totally ablated. The purpose of this report is to describe the ERG in INCL, LINCL and JNCL. The ERGs of 7 patients who were examined by the author over the past 15 years were reviewed. Ganzfeld ERG responses were recorded using the ISCEV standard protocol and an intensity response series over a 3.7 log unit range. The earliest ERG manifestation of INCL is a marked loss of the scotopic and photopic b-wave with relative preservation of the a-wave; this defect, which was evident for both rods and cones, suggests preservation of photoreceptor outer segment function with severe disturbance of transmission of the signal to the second-order neuron, the bipolar cells. For LINCL, the rod responses were mildly abnormal but more preserved than in INCL or JNCL. The cone b-wave amplitudes in patients with early LINCL were severely subnormal with prolonged implicit times. Patients with JNCL invariably showed severe to profound ERG abnormalities when first tested, with essentially no rod-mediated activity and marked loss of a-wave amplitudes with even greater loss of b-wave amplitudes, creating electronegative configuration waveforms. Differences in the ERG responses were thus found that provide further clues to the earliest site of pathology within the retina.
神经元蜡样脂褐质沉积症（NCL）是一类神经退行性疾病，伴有精神运动发育迟缓、癫痫发作、视力减退和过早死亡，所有这些都与溶酶体内脂蛋白的异常蓄积有关。NCL最常见的形式为婴儿型（婴儿型NCL，CLN1）、晚婴儿型（晚婴儿型NCL，CLN2）和青少年型（青少年型NCL，CLN3）。在这三种类型中，早期视网膜电图（ERG）均异常，最终完全消失。本报告旨在描述婴儿型NCL、晚婴儿型NCL和青少年型NCL的ERG情况。回顾了作者在过去15年中检查的7例患者的ERG。使用国际临床视觉电生理学会（ISCEV）标准方案记录全视野ERG反应，并在3.7对数单位范围内记录强度反应系列。婴儿型NCL最早的ERG表现是暗视和明视b波明显缺失，而a波相对保留；这种缺陷在视杆细胞和视锥细胞中均很明显，提示光感受器外段功能保留，但信号向二级神经元双极细胞的传递受到严重干扰。对于晚婴儿型NCL，视杆细胞反应轻度异常，但比婴儿型NCL或青少年型NCL保留得更多。早期晚婴儿型NCL患者的视锥细胞b波振幅严重低于正常，潜伏期延长。青少年型NCL患者首次检测时总是表现出严重至极重度的ERG异常，基本上没有视杆细胞介导的活动，a波振幅明显降低，b波振幅降低更明显，形成负性配置波形。因此发现了ERG反应的差异，为视网膜内最早的病理部位提供了进一步线索。
