objective To observe the differences between four- and single-channel recording of normal multifocal visual evoked potential (mfVEP). Methods mfVEP of 35 health individuals (70 eyes) were detected by both four- and single-channel recording with VERIS apparatus. The root mean square (RMS) value of reactive amplitude was obtained from the results of the two kinds of recording. Each stimulated patch was analyzed to compare the variational degree of each patch between the two recording methods. Responase sasymmetry coefficient (RAC) was introduced to evaluate the symmetry property between the two eyes in an individual. Results Compared with the single-channel recording,the responses of the stimulated patches of the four- channel recording were increased statistically, with most of the patches below the horizontal meridian and some of patches in the upper field, and there was distinct symmetry property between the two eyes in the same individual recorded by four-channel recording. Conclusion The four-channel recording is better than the single one and could be clinically applied and popularized.(Chin J Ocul Fundus Dis，2004，20：156-159)
Objective To observe the changes of disease course and the prognosis of visual acuity of Chinese patients with polypoidal choroidal vasculopathy ( PCV).Methods Visual acuity and fundus photochromes of 20 eyes of 15 consec utive patients with PCV were followed up with a mean of 19.1 months (range from 2 to 64 months), in which the fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) of 14 eyes of 10 patients were followed up with a mean of 21.0 (range from 3 to 53) months.Results Among the 20 eyes, the visual acuity was more than 0.3 in 5 eyes (25.0%), between 0.1 and 0.2 in 6 (30%) and less than 0.1 in 9 (45.0%). During the follow-up, the visual acuity was improved in 2 (10.0%), stable in 10 (50.0%)), and regressed in 8 (40.0%). Only 1 eye (5.0 %) developed to macula scar. The result of ICGA revealed the polypoidal lesions that were unchanged in 4 eyes(28.6%), regressed in 2 (14.3%), grew in 6 (42.7%), repeatedly grew and spontaneously regressed in 6 (42.7%).Conclusions There is a large variation in the visual prognosis in Chinese patients with PCV. The polypoidal lesions can repeatedly grow and spontaneously regress in the natural course. (Chin J Ocul Fundus Dis，2004，20：8-11)
Objective To assess the change of the motion perception of cones in patients with AMD. Methods Motion perceptions of B、G and R cones of 20 eyes with dry type AMD were isolated by blue,green and red random dots stimulus displayed on the yellow,purple and blue-green background respectively,and keeping equiluminance between stimulus and background. Results The detecting displacement threshold and identifying threshold of motion perception from B,G and R cones were all damaged in eyes with dry type AMD compared with the normal group. Conclusion The abnormal changes of motion perception may reveal preclinical damage of visual function damage in dry type AMD. (Chin J Ocul Fundus Dis, 1999, 15: 219-221)