scholarly journals Influence of pupil size and other test variables on visual function assessment using visual evoked potentials in normal subjects

2010 ◽  
Vol 121 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Sarwat Salim ◽  
Kevin Childers ◽  
Alvaro P. C. Lupinacci ◽  
George Z. Hu ◽  
Vance Zemon ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Visual Function ◽  
Pupil Size ◽  
Normal Subjects ◽  
Function Assessment ◽  
Visual Evoked

Nonlinear Analysis of Visual Evoked Potentials Elicited by Color Stimulation

1997 ◽  
Vol 36 (04/05) ◽  
pp. 315-318 ◽  
Author(s):  
K. Momose ◽  
K. Komiya ◽  
A. Uchiyama
Keyword(s):  
Visual System ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Normal Subjects ◽  
Second Order ◽  
First Order ◽  
The Relationship ◽  
Perceived Color ◽  
Second Order Nonlinearity ◽  
Visual Evoked

Abstract:The relationship between chromatically modulated stimuli and visual evoked potentials (VEPs) was considered. VEPs of normal subjects elicited by chromatically modulated stimuli were measured under several color adaptations, and their binary kernels were estimated. Up to the second-order, binary kernels obtained from VEPs were so characteristic that the VEP-chromatic modulation system showed second-order nonlinearity. First-order binary kernels depended on the color of the stimulus and adaptation, whereas second-order kernels showed almost no difference. This result indicates that the waveforms of first-order binary kernels reflect perceived color (hue). This supports the suggestion that kernels of VEPs include color responses, and could be used as a probe with which to examine the color visual system.

Effect of pupil size on multifocal pattern visual evoked potentials

2003 ◽  
Vol 31 (4) ◽  
pp. 354-356 ◽  
Author(s):  
Alessandra Martins ◽  
Chandra Balachandran ◽  
Alexander I Klistorner ◽  
Stuart L Graham ◽  
Francis A Billson
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Pupil Size ◽  
Pattern Visual Evoked Potentials ◽  
Visual Evoked

scholarly journals Cortical Contrast Processing in Retinitis Pigmentosa: Evidence of PVEPs Spatial Functions

2020 ◽  
Vol 10 (4) ◽  
pp. 1010-1019
Author(s):  
Rafael Mancebo-Azor ◽  
José Antonio Sáez-Moreno ◽  
José Manuel Rodríguez-Ferrer
Keyword(s):  
Retinitis Pigmentosa ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Normal Subjects ◽  
Pattern Reversal ◽  
Check Size ◽  
Low Contrast ◽  
Control Subjects ◽  
The Right ◽  
Visual Evoked

Objective: To study the effect of check width size of the stimuli on the amplitude and latency of the P100 component of visual evoked potentials recorded in patients with retinitis pigmentosa (RP). Methods: Pattern reversal visual evoked potentials (PVEPs) were recorded in 16 RP patients and 20 visually normal subjects. Pattern reversal stimuli with five different check widths and 100% of contrast were projected in the right eye of both patients and control subjects. PVEPs induced by stimuli with 78%, 16%, and 6% of contrast were also recorded in 10 of the control subjects. Results: In RP patients, the amplitude of P100 was smaller than controls in all check sized used and the peak P100 amplitude was obtained with a larger check width than in controls. P100 was also delayed in RP patients in all check sizes studied. The P100 amplitude- and latency-check size functions of RP patients were like those found in control subjects with low contrast stimuli of 16% and 6%. Conclusion: The PVEPs spatial functions of RP patients show quantitative and qualitative changes, suggesting disease induced alteration in the neural processing of stimulus contrast.

Multifocal visual-evoked potentials in patients with schizophrenia during treatment

2011 ◽  
Vol 23 (1) ◽  
pp. 31-34 ◽  
Author(s):  
Mariko Yamada ◽  
Eiichi Yukawa ◽  
Futoshi Taketani ◽  
Toyoaki Matsuura ◽  
Yoshiaki Hara
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Normal Subjects ◽  
Subject Group ◽  
Recording Apparatus ◽  
Multifocal Visual Evoked Potentials ◽  
Psychotropic Agents ◽  
Schizophrenic Patients ◽  
Conventional Perimetry ◽  
Visual Evoked

Aim: Investigation of responses of multifocal visual-evoked potentials (mfVEPs) in schizophrenic patients under treatment in whom no abnormality was detected on the conventional perimetry.Methods: Recordings of mfVEPs were performed in 31 schizophrenic patients and 30 normal subjects using a VERIS Junior Science recording apparatus (Mayo, Aichi, Japan). Responses from eight sites in each subject were divided into four quadrants (superior and inferior temporal quadrants, and superior and inferior nasal quadrants). In each quadrant, two response waves were grouped and averaged, and the latency and amplitude of main waveforms that appeared near 100 ms were evaluated.Results: The peak latency was about 7–9 ms prolonged and the amplitude was reduced by about 2–5 nV/deg2 in the schizophrenic patient group compared to those in the normal subject group, and significant differences were noted in both parameters in all quadrants.Conclusion: In schizophrenic patients under treatment with psychotropic agents, prolongation of the latency and amplitude reduction were noted in mfVEPs even though no abnormality was detected on the conventional perimetry.

Steady-State Visual-Evoked Potentials in Headache: Diagnostic Value in Migraine and Tension-Type Headache Patients

Cephalalgia ◽  
1999 ◽  
Vol 19 (1) ◽  
pp. 23-26 ◽  
Author(s):  
M de Tommaso ◽  
V Sciruicchio ◽  
M Guido ◽  
G Sasanelli ◽  
F Puca
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Visual Stimulation ◽  
Normal Subjects ◽  
Tension Type Headache ◽  
Brain Response ◽  
Mean Values ◽  
Type Headache ◽  
Headache Patients ◽  
Visual Evoked

We tested the hypothesis that migraine and tension-type headache are separate disorders based on visual evoked potentials. We recruited 120 migraine without aura patients (MwoA), 64 tension-type headache patients (TTH), and 51 healthy controls. We performed discriminant analysis combined with a stepwise selection of predictors. Mean values of the F1 component were significantly increased over Fp1, C3, P4, O2 and O1 electrodes in MwoA and TTH patients compared with normal subjects. Only the control subjects were correctly distinguished. The increased brain response to visual stimulation detected in both MwoA and TTH may suggest a common neuronal dysfunction in the two headache subtypes.

scholarly journals Visual evoked potentials in veterinary ophthalmology: literature review

2019 ◽  
Vol 2019 (5) ◽  
pp. 23-29
Author(s):  
Артем Миронович ◽  
Artem Mironovich ◽  
Сергей Бояринов ◽  
Sergey Boyarinov
Keyword(s):  
Nervous System ◽  
Literature Review ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Visual Function ◽  
Research Method ◽  
Structural Changes ◽  
Complete Loss ◽  
Diagnostic Research ◽  
Visual Evoked

Diagnosis of causes of blindness in veterinary ophthalmology is an urgent issue. There are a large number of diseases of central and peripheral nervous system, which can lead to partial or complete loss of visual function in animals. Visual evoked potentials (VEP) of brain can be a reliable diagnostic research method to clarify the location of the disfunction and causes of blindness in dogs and cats. Together, the visual evoked potentials and electroretinography complement each other and give a greater idea of electrophysiology of visual process. In this article on the basis of large quantity of information we examine the ways of applying this method and the problems, connected with its use. It is important to understand that the VEP can reveal the functional disturbances of visual way, but does not give the information about the structural changes.

scholarly journals Intraoperative monitoring of visual evoked potentials in patients undergoing transsphenoidal surgery for pituitary adenoma: a systematic review

BMC Neurology ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Farizeh Jashek-Ahmed ◽  
Ivan Cabrilo ◽  
Jarnail Bal ◽  
Brett Sanders ◽  
Joan Grieve ◽  
...  
Keyword(s):  
Pituitary Adenoma ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Visual Function ◽  
Transsphenoidal Surgery ◽  
Intraoperative Monitoring ◽  
Case Series ◽  
Warning Sign ◽  
Published Evidence ◽  
Visual Evoked

Abstract Background Transsphenoidal surgery is the gold standard for pituitary adenoma resection. Although rare, a serious complication of surgery is worsened vision post-operatively. Objective To determine whether, in patients undergoing transsphenoidal surgery for pituitary adenoma, intraoperative monitoring of visual evoked potentials (VEP) is a safe, reproducible, and effective technological adjunct in predicting postoperative visual function. Methods The PubMed and OVID platforms were searched between January 1993 and December 2020 to identify publications that (1) featured patients undergoing transsphenoidal surgery for pituitary adenoma, (2) used intraoperative optic nerve monitoring with VEP and (3) reported on safety or effectiveness. Reference lists were cross-checked and expert opinion sought to identify further publications. Results Eleven studies were included comprising ten case series and one prospective cohort study. All employed techniques to improve reliability. No safety issues were reported. The only comparative study included described a statistically significant improvement in post-operative visual field testing when VEP monitoring was used. The remaining case-series varied in conclusion. In nine studies, surgical manipulation was halted in the event of a VEP amplitude decrease suggesting a widespread consensus that this is a warning sign of injury to the anterior optic apparatus. Conclusions Despite limited and low-quality published evidence regarding intra-operative VEP monitoring, our review suggests that it is a safe, reproducible, and increasingly effective technique of predicting postoperative visual deficits. Further studies specific to transsphenoidal surgery are required to determine its utility in protecting visual function in the resection of complex pituitary tumours.

Case Report of Multiple Sclerosis in Which Visual Function Was Evaluated Using Multifocal Visual Evoked Potentials

2007 ◽  
Vol 51 (2) ◽  
pp. 153-155 ◽  
Author(s):  
Eiichi Yukawa ◽  
Yeong-Jin Kim ◽  
Tetsuo Ueda ◽  
Yoshiaki Hara
Keyword(s):  
Multiple Sclerosis ◽  
Case Report ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Visual Function ◽  
Multifocal Visual Evoked Potentials ◽  
Visual Evoked
Sign in / Sign up

Export Citation Format

Share Document