Use of 10-Hz flash visual evoked potentials in prediction of final visual acuity in diabetic eyes with vitreous hemorrhage

Abstract

In 44 diabetic eyes with vitreous hemorrhage, monocular steady-state visual evoked potentials were elicited through closed eyes by a 10-Hz flash. Visual evoked potentials were rated as normal or abnormal on the basis of amplitude and waveform. Abnormal visual evoked potentials were subdivided into mildly abnormal, markedly abnormal and nonrecordable categories. Patients with normal potentials were predicted to have visual acuities of 6/15 (20/50) or better. Patients with abnormal potentials were predicted to have visual acuities of 6/18 (20/60) or worse. Final visual acuities were the best visual acuities recorded in the 6 months after vitreous surgery (vitrectomy) or spontaneous clearing of the vitreous hemorrhage. The visual evoked potential categories and final acuities were compared with a 2 x 2 contingency table. The accuracy was 86%. The visual evoked potential categories and final acuities were associated at a statistically significant level.

Effects of wavelength on the timing and laminar distribution of illuminance-evoked activity in macaque V1

“…Of particular note is the fact that, relative to blue and green, red flash produces the shortest latency responses, psychophysically and electrophysiologically (see White et al, 1986). The red-specific effects noted here may also bear on several clinical findings, for example, the fact that with cataracts (Odom et al, 1987(Odom et al, , 1988Cavender et al, 1992) and vitreous hemorrhage (Vadrevu et al, 1992), flash VEPs provide a useful predictor of postoperative or otherwise final macular (acuity) function. A common factor in much of this work is that because of the use of red LED stimulators, stimulation through closed eyelids or blood in the vitreous much of the stimulus energy is in a range corresponding to red.…”

Assessment of Human Visual Acuity Using Visual Evoked Potential: A Review

“…The gap between the neighboring black and white parts represents the spatial frequency of the stimulus. Some studies used a simple pattern of flashes to predict the final visual acuity of patients with cataracts, diabetes, and other severe ocular injuries by VEP [ 32 , 33 , 34 , 35 ]. Towle and Harter [ 10 ] used a dot pattern rather than a checkerboard since the perception of the dot pattern would be less influenced by cylindrical refractive errors.…”

“…Figure 5 shows the percentages of stimulus modulated modes in the selected studies. Except for the motion mode of oscillating expansion and contraction [ 7 ] and the flash mode in several studies [ 32 , 33 , 34 , 35 ], the most used stimulus modes were pattern-reversal and pattern onset-offset, with proportions of 71% and 24%, respectively.…”

“…In addition, Vadrevu et al [ 33 ] tested SSVEP on diabetic eyes with vitreous hemorrhage using a 10 Hz flash and assessed the utility of SSVEP in predicting the final visual acuity of these patients. Faria et al [ 82 ] evaluated visual abnormalities without retinopathy in patients with type 1 diabetes mellitus by the VEP method and found that those patients demonstrated significant lower VEP amplitude at all spatial frequencies compared with normal subjects, indicating an optic nerve dysfunction in patients with type 1 diabetes mellitus.…”

“…Figure 5 shows the percentages of stimulus modulated modes in the selected studies. Except for the motion mode of oscillating expansion and contraction [7] and the flash mode in several studies [32][33][34][35], the most used stimulus modes were pattern-reversal and pattern onset-offset, with proportions of 71% and 24%, respectively. The two common modes of pattern-reversal and onset-offset are illustrated schematically in Figure 6, taking vertical sine-wave gratings as an example.…”