Sano Marie, Tazawa Yutaka, Nabeshima Takashi, Mita Mariko
Department of Ophthalmology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan.
Invest Ophthalmol Vis Sci. 2002 May;43(5):1666-72.
To report the properties of a newly detected positive wavelet on the descending limb of P1 of the first-order kernel of the human multifocal electroretinogram (mfERG).
Twenty eyes of 20 normal individuals, ages 21 to 29 years (mean, 25.6) and nine eyes of 6 patients with optic neuritis ages 5 to 38 years (mean, 17.3) were studied. mfERGs were recorded with a visual evoked response imaging system with the number of stimulus elements set at 37. The stimulus frequency was changed from 75 to 37, 18, 9.4, 4.7, and 2.3 Hz, and the contrast of the stimuli was lowered to 50%.
In normal eyes, a positive wavelet appeared on the descending limb of P1 of the first-order kernel of the mfERG when the stimulus frequency was reduced from 75 to 18 Hz. The wavelet had a mean amplitude of 4.2 nV/deg(2) and a mean implicit time of 34 ms at 18 Hz. When the stimulus frequency was reduced further to 2.3 Hz, the amplitude of the wavelet increased significantly (P < 0.05) compared with that at 18 Hz. The amplitudes of the wavelet elicited from the nasal side of the retina were significantly larger (P < 0.05) than those from the temporal side and decreased significantly (P < 0.05) with increasing distance from the optic disc. The wavelet was not present in any of the patients with newly diagnosed optic neuritis, but reappeared with recovery from the disease. The recovery of the wavelet correlated significantly with the recovery of visual acuity and of central critical fusion frequency.
The amplitude of the wavelet on the descending limb of P1 of the first-order kernel of the mfERG was dependent on the stimulus frequency and the retinal locus. The wavelet was not present in the mfERGs recorded in patients with optic neuritis, but returned with recovery from the disease. These findings suggest that the neural activity of the ganglion cells give rise to this wavelet.
报告在人类多焦视网膜电图（mfERG）一阶核P1下降支上新检测到的正小波的特性。
研究了20名年龄在21至29岁（平均25.6岁）的正常个体的20只眼睛，以及6名年龄在5至38岁（平均17.3岁）的视神经炎患者的9只眼睛。使用视觉诱发电位成像系统记录mfERG，刺激单元数量设置为37。刺激频率从75Hz变为37Hz、18Hz、9.4Hz、4.7Hz和2.3Hz，刺激对比度降低到50%。
在正常眼睛中，当刺激频率从75Hz降低到18Hz时，mfERG一阶核P1下降支上出现一个正小波。该小波在18Hz时平均振幅为4.2nV/deg(2)，平均隐含时间为34ms。当刺激频率进一步降低到2.3Hz时，与18Hz时相比，小波振幅显著增加（P<0.05）。从视网膜鼻侧引出的小波振幅明显大于颞侧（P<0.05），并随着与视盘距离的增加而显著降低（P<0.05）。新诊断的视神经炎患者中均未出现该小波，但随着疾病恢复而重新出现。小波的恢复与视力和中央临界融合频率的恢复显著相关。
mfERG一阶核P1下降支上小波的振幅取决于刺激频率和视网膜部位。视神经炎患者记录的mfERG中不存在该小波，但随着疾病恢复而恢复。这些发现表明神经节细胞的神经活动产生了这个小波。
