Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018681 (headache)
 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty patients with migraine with visual aura, aged 19 to 55 years (2 men and 18 women) were studied by the method of Visual Evoked Potentials (VEP). The control group consisted of an equal number of healthy subjects, comparable for age and sex. The most important finding in our study is that migraine patients with visual prodromata have a significantly longer P100 latency than the subjects of control group. These modifications of the VEP-PR could indicate, as other investigators have pointed out, that there are some special metabolic conditions and abnormalities of neuromediators during and between attacks.
Headache 1990 Jun
PMID:Pattern reversal visual evoked potentials (VEP-PR) in migraine subjects with visual aura. 240 26

An experiment is described which compared visual evoked potential (VEP) amplitudes and latencies in normal subjects and migraine patients. Several VEP abnormalities were found: at vertex and to a lesser extent at temporal sites, P100-N120 amplitudes were larger in patients; at vertex and temporal sites N120 amplitudes were larger in patients; at temporal sites patents had larger N120-P200 amplitudes but smaller P100 amplitudes. Peak latencies of the VEP were also found to be abnormal in patients. At vertex, patients had delayed N120 peak latencies while at temporal sites delays were found in the P200 latencies. Patients were subdivided according to side of headache. Right-sided headache patients showed larger temporal P100 amplitudes and larger left temporal P100-N120 amplitudes than bilateral headache patients.
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PMID:Migraine patients exhibit abnormalities in the visual evoked potential. 628 33

A study of hemi-field pattern reversal visual evoked potentials recorded in the interictal phase was carried out in 44 patients (22 with migraine with aura, 22 without aura) in order to determine whether migraine patients with or without aura and with headaches with strong unilateral predominance, either left or right, exhibit abnormalities after hemi-field stimulation. No differences of P100 latency were found between them and a group of 20 normal individuals, between patients suffering from migraine with aura and migraine without aura and between the affected and the non-affected side of the head. Only in a subgroup of 14 patients with headaches constantly lateralized to a single side, either left or right, was the P100 latency significantly shorter on the affected side (p < 0.001, t-test) compared with the contralateral non-affected side. The results indicate that in both types of migraine there is a common underlying pathogenetic mechanism and the affected retrochiasmatic optic radiation has an increased response to sensory input modulation.
Cephalalgia 1993 Aug
PMID:Hemi-field pattern reversal visual evoked potentials in migraine. 837 42

A 5-year-old boy with left side optic neuritis, which manifested itself 21 days after the onset of rubella eruption, is reported. Seven days after the onset of rash which persisted for 3 days, he was found to be excessively somnolent and disoriented, and a diagnosis of rubella encephalitis was made at our clinic. Clinical symptoms spontaneously subsided 3 days later. Twenty-one days after the appearance of rash (16 days after the onset of encephalitis) he complained of left frontal headache and blurred vision of left eye. The funduscopic examination revealed the left papillitis. Pattern reversal VEP (PVEPs) evoked by stimuli of left eye showed absence of N75 wave, and a prolonged conduction time and low amplitude of P100 wave. Corticosteroid therapy improved his complaints, funduscopic and PVEPs findings. When the treatment was stopped, the funduscopic findings were exacerbated but were improved soon again by the additional corticosteroid therapy. A delayed onset of optic neuritis after the initial infection and a prompt response to corticosteroid therapy may suggest an involvement of some autoimmune process in the pathogenesis of postinfectious optic neuritis in our case.
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PMID:[A case of optic neuritis following rubella encephalitis]. 839 34

Pattern reversal visual evoked potentials were recorded in 71 children with different types of migraine (e.g. migraine with aura, migraine without aura) or tension-type headache and in 19 controls (mean age of both groups 9 years). P100 latencies were comparable in all three groups.
Cephalalgia 1996 Apr
PMID:Pattern reversal visual evoked potentials in children with migraine or tension-type headache. 866 85

Visual evoked potentials (VEPs) were performed in a blind fashion in 114 children aged 3 to 17 years with different types of headaches, in order to investigate whether this could be helpful in the diagnosis of migraine versus other types of headaches in children. The study showed that the amplitude between P100 and N2 was significantly larger in children with migraine headaches (mean 19.8 microvol, SD 7.75) compared with other types of headaches (mean 13.1 microvol, SD 7.45). These results suggest that the sensitivity of VEP P100 amplitude to distinguish migraine headaches in children is 67%, the specificity of VEP is 83%, and the predictive positive value is 83%. VEP study might be helpful in work-up of a child with headache, particularly a young child, when signs and symptoms may not be characteristic.
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PMID:Visual evoked potentials: a diagnostic test for migraine headache in children. 928 42

Changes in visual evoked potentials and decreased intracellular magnesium levels have been separately described in patients affected by migraine both during the attacks and in the interictal periods. An inverse correlation between increased P100 amplitude and lowered serum magnesium levels was found in children suffering from migraine with and without aura in a headache-free period. A 20-day treatment with oral magnesium pidolate seemed to normalize the magnesium balance in 90% of patients. After treatment, the reduced P100 amplitude confirmed the inverse correlation with the serum magnesium level. These data seem to suggest the hypothesis that higher visual evoked potential amplitude and low brain magnesium level can both be an expression of neuronal hyperexcitability of the visual pathways related to a lowered threshold for migraine attacks.
Headache 1997 Jun
PMID:Visual evoked potentials and serum magnesium levels in juvenile migraine patients. 923 12

To determine the possible electrophysiologic changes in migraineurs with or without visual aura, we investigated pattern-reversal visual evoked potentials in 39 patients. We compared the mean P100 latency and amplitude of 16 patients with aura, 23 patients without aura, and 17 age- and sex-matched normal subjects. There were no significant differences between groups. There was no correlation between age and the parameters in any group. However, in 7 of 23 patients without aura, the P100 latency was longer than the mean control value +2 SD. The mean disease duration in this subgroup was significantly longer than the means of the remaining 16 patients without aura or the patients with aura (P < 0.05 for each). This suggests the possibility that P100 latency prolongation is a consequence, but not an entity caused by the pathogenetic mechanism of the disease from the beginning.
Headache
PMID:Pattern-reversal visual evoked potentials in migraineurs with or without visual aura. 927 29

Changes in visual evoked potentials, mainly affecting the amplitude of the major positive wave, are referred to by many authors and are related to the pathophysiological basis of primary headache. We performed both transient pattern-reversal visual evoked potentials and spectral analysis by means of fast Fourier transform of 8-Hz steady-state pattern-reversal visual evoked potentials in 34 children affected with migraine (14 with aura, 20 without aura), and compared them with 14 patients with tension-type headache and 10 healthy subjects. The amplitude of the response to the transient stimulation (P100) was higher and the latency shorter in the patients with headache compared with the controls, but the difference was not statistically significant. The absolute power of the first harmonic (1F) obtained by the spectral analysis of the steady-state stimulation was increased in all the patients with headache compared with the controls, and the increase was significant in patients with migraine. These data seem to confirm the hypothesis of abnormal processing of visual input in migraineurs and could be interpreted as neurophysiological support for the theory that different headache types are related conditions. Furthermore, the spectral analysis of steady-state pattern-reversal visual evoked potentials could be proposed as a test to diagnose migraine.
Headache 2001 Sep
PMID:Spectral analysis of visual potentials evoked by pattern-reversal checkerboard in juvenile patients with headache. 1157 4

The N70 and P100 components of transient pattern visual evoked potentials (P-VEPs) were measured in migraine patients, with and without aura, and in normal subjects in order to evaluate their latency, amplitude and occipital scalp distribution. The aim was to find any typical electrophysiological abnormalities in migraine. P-VEP N70 and P100 were analyzed in 59 patients without any known visual field defect. Mean latency and amplitude values were within normal ranges for either N70 and P100 all over the occipital scalp; the only significant abnormality we found was related to the absolute right-left amplitude ratio either for N70 and P100 waves, providing an asymmetry in P-VEP scalp distribution; this finding was detected in 78.9% of patients with aura and 72.5% without aura. Our results show that in migraine patients, both P-VEP waves N70 and P100, have an asymmetric topographic distribution, even during interictal phases, that can be explained by a cortical disturbance in agreement with the neural hypothesis of headache.
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PMID:Asymmetric scalp distribution of pattern visual evoked potentials during interictal phases in migraine. 1169 25


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