Responsiveness of the Visual System in Childhood Migraine Studied by Means of VEPs

We have tried to ascertain whether the increased visual evoked potential (VEP) amplitude found in adult migraineurs is present also in children with migraine. We investigated 43 children, 26 male and 17 female, with a mean age of 11.4 years, 24 with common and 19 with classic migraine, and compared them with a control group of 20 children, 11 male and 9 female, with a mean age of 9.7 years. Flash and pattern reversal VEPs were recorded in both groups, and the study was carried out in the pain-free interval between attacks. The children with migraine showed a significant ( p < 0.01) increase in VEP amplitude on flash stimulation but not on pattern reversal. There were no differences between classic and common migraine. The abnormal responsiveness of the visual system seems to be related to variations in light intensity rather than to spatial contrasts.

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Primary Presenile Dementia: The Use of the Visual Evoked Potential as a Diagnostic Indicator

The British Journal of Psychiatry ◽

10.1192/bjp.147.5.532 ◽

1985 ◽

Vol 147 (5) ◽

pp. 532-539 ◽

Cited By ~ 32

Author(s):

Graham F. A. Harding ◽

Christine E. Wright ◽

Arnold Orwin

Keyword(s):

Visual Evoked Potential ◽

Evoked Potential ◽

Cortical Atrophy ◽

Control Group ◽

Pattern Reversal ◽

Presenile Dementia ◽

The Difference ◽

Pattern Reversal Stimulation ◽

Diagnostic Indicator ◽

Visual Evoked

The use of the flash and pattern reversal visual evoked potential (VEP) in the diagnosis of primary presenile dementia was investigated. The results from 20 patients with primary presenile dementia were compared with those from a control group of normals of equivalent age and from a control group of 20 patients with cortical atrophy but no dementia. Presenile dementia caused a slowing of the major positive (P2) component of the VEP to flash stimulation. However, the VEP to pattern reversal stimulation (P100) was of normal latency. The difference between these two latencies characterises this unusual combination of results and is found to be a more specific diagnostic indicator of primary presenile dementia than the EEG or CT scan.

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Visual Evoked potential signal processing and analysis for normal and galucomic eyes

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v8i2.1516 ◽

2015 ◽

Vol 8 (2) ◽

pp. 2106-2121

Author(s):

Hamed Ibrahem Abdelkader ◽

Mona Abdelkader ◽

Mohammed Kabeel ◽

Malak Alya

Keyword(s):

Evoked Potentials ◽

Visual Evoked Potential ◽

Evoked Potential ◽

Optic Tract ◽

Pattern Reversal ◽

Blue Color ◽

Check Size ◽

Retinal Stimulation ◽

Normal Individuals ◽

Visual Evoked

Visual evoked potentials (VEPS) are obtained from optic tract by recording the evoked potentials generated by retinal stimulation. The flash VEP (FVEP) is used less frequently than pattern reversal VEP (PRVEP) because; it shows great variation in both latency and amplitude. The present study was undertaken to evaluate the effect of change of wavelength of flash and change of check size on the parameters of visual evoked potential (amplitude and latency) in normal individuals and glaucoma patients. The group of healthy subjects in the age of 20-45 years while the group of glaucoma subjects where Â in the age of 25-50 years. Â The two groups were exposed to flash VEP with white light and blue color and they also were exposed to checks subtending a visual angles of 15, 30,60 and 120 minutes of arc. The measured data were statistically analyzed and summarized by histograms. The interindividual and intraindividual in latencies and amplitudes for FVEP were assessed using Â the coefficient of variation (COV). In conclusion, monochromatic flash VEP was preferred than white as there were minimal inter and intra individual variation of latencies and amplitudes. The most preferred check size in PRVEP was 120' for Â the two groups.Â Â

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