TY - JOUR
T1 - Application of visual evoked potentials for preoperative estimation of visual function in eyes with dense cataract
AU - Mori, Hiroshi
AU - Momose, Keiko
AU - Nemoto, Nobuyuki
AU - Okuyama, Fumio
AU - Kimura, Yuichi
AU - Kiyosawa, Motohiro
AU - Mochizuki, Manabu
PY - 2001/1/1
Y1 - 2001/1/1
N2 - Purpose: To determine whether the temporal frequency characteristics of the visual system as determined by visually evoked potentials (VEP) can be used for a preoperative estimation of the visual function in eyes with cataracts. Methods: Light stimuli driven by a pseudorandom binary sequence (PRBS) of 40950 ms duration were presented and EEG recordings were made from 13 control and 20 patients with cataracts preoperatively and 1 week after cataract operation. The first kernel of the PRBS-VEP was obtained as the first-order cross-correlation function between PRBS and PRBS-VEP. The Fourier transform of this function was used as the temporal frequency characteristic (TFC). Results: The mean ± standard deviation of the latency and amplitude of the VEP in normal controls were 110.8±4.3 ms and 2.01±0.67 μV, respectively. A high correlation (r>0.7) between the pre- and postoperative VEP waveform was obtained in 13 eyes (65%), and 14 eyes (70%) in the VEP-TFC curves. The sensitivity of the examination was 73%, 27%, and 91% for the latency, amplitude and TFC of the VEP, respectively. The specificity of the examination was 67%, 100%, and 89% for the same measures. Eleven of 12 eyes with abnormal TFC preoperatively showed retinal or optic nerve lesions postoperatively. False-negative results were seen in cases with delayed corneal edema. Conclusion: Postoperative visual function of patients with cataracts can be predicted by preoperative measurement of the TFC obtained by PRBS-VEP.
AB - Purpose: To determine whether the temporal frequency characteristics of the visual system as determined by visually evoked potentials (VEP) can be used for a preoperative estimation of the visual function in eyes with cataracts. Methods: Light stimuli driven by a pseudorandom binary sequence (PRBS) of 40950 ms duration were presented and EEG recordings were made from 13 control and 20 patients with cataracts preoperatively and 1 week after cataract operation. The first kernel of the PRBS-VEP was obtained as the first-order cross-correlation function between PRBS and PRBS-VEP. The Fourier transform of this function was used as the temporal frequency characteristic (TFC). Results: The mean ± standard deviation of the latency and amplitude of the VEP in normal controls were 110.8±4.3 ms and 2.01±0.67 μV, respectively. A high correlation (r>0.7) between the pre- and postoperative VEP waveform was obtained in 13 eyes (65%), and 14 eyes (70%) in the VEP-TFC curves. The sensitivity of the examination was 73%, 27%, and 91% for the latency, amplitude and TFC of the VEP, respectively. The specificity of the examination was 67%, 100%, and 89% for the same measures. Eleven of 12 eyes with abnormal TFC preoperatively showed retinal or optic nerve lesions postoperatively. False-negative results were seen in cases with delayed corneal edema. Conclusion: Postoperative visual function of patients with cataracts can be predicted by preoperative measurement of the TFC obtained by PRBS-VEP.
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U2 - 10.1007/s00417-001-0390-6
DO - 10.1007/s00417-001-0390-6
M3 - Article
C2 - 11820696
AN - SCOPUS:0035664541
SN - 0721-832X
VL - 239
SP - 915
EP - 922
JO - Graefe's Archive for Clinical and Experimental Ophthalmology
JF - Graefe's Archive for Clinical and Experimental Ophthalmology
IS - 12
ER -