Normalisation of visual evoked potentials after optic neuritis.

Background: The aim was to compare the retinal nerve fibre layer (RNFL) thickness and visual evoked potentials (VEP) among eyes with multiple sclerosis (MS)‐associated optic neuritis, unaffected eyes of the same patients and eyes of disease‐free controls. Changes in RNFL thickness, visual acuity (VA) and VEP over time are evaluated in MS‐associated optic neuritis.Methods: Forty‐six eyes of 23 patients (six male and 17 female), who suffer from MS and were diagnosed with unilateral or bilateral optic neuritis, participated in the study. Forty eyes of 20 age‐ and gender‐matched controls were tested. VA measurement, optical coherence tomography and VEP were performed in all patients at presentation and at one, three and six months thereafter.Results: There was a statistically significant difference in VA between MS eyes with optic neuritis and controls (p < 0.0001), as well as between MS eyes with and without optic neuritis (p < 0.005). VA improved over time. Average RNFL thickness was reduced in MS eyes with or without optic neuritis in comparison to control eyes. This reduction in RNFL thickness was more marked over time. The amplitude of P100 was significantly decreased in MS eyes with optic neuritis in comparison to controls (p < 0.0001) and there was a statistically significant delay in peak time of P100 in MS eyes with optic neuritis versus the eyes of normal subjects (p < 0.0001), which improved over time.Conclusion: The present study suggests that there is a progressive decrease in RNFL over time in eyes with optic neuritis associated with MS. The amplitude and latency of P100 in VEP examination returned to normal ranges over time.

Objective: To examine the association of visual evoked potential (VEP) latency and high-contrast visual acuity (VA) with cognitive function in MS patients using a standardized computerized battery. Background Cognition and vision are now recognized as important domains for clinical trials assessment in MS. The correlation of VEP conduction delay and VA with cognitive impairment has not been described. Design/Methods: Participants received a VEP evaluation as well as a Snellen vision test and completed a standardized, validated MindStreams battery designed to detect mild impairment (NeuroTrax Corp., NY) in their primary language. VEP latency categories were: normal =113 and =130 and =150 and 170 msec. Results: Among MS patients (n=435, 870 eyes), Accounting for age, disease duration, and within-patient, inter-eye correlations, abnormal VEP latency was associated with poorer overall battery performance (Global Cognitive Score, p Conclusions: Abnormal VEP latency and high-contrast VA in patients with MS may be associated with reduced cognitive function, particularly in domains related to executive function. Longer VEP latency may be particularly related to poorer visual spatial processing. Further studies will examine the role of afferent visual dysfunction and retinal axonal and neuronal loss in the relation of VEP latency to cognitive impairment and work disability in MS cohorts. Disclosure: Dr. Chahin has nothing to disclose. Dr. Balcer has received personal compensation for activities with Biogen Idec, Vaccinex and Bayer as a consultant and has received honoraria from Biogen Idec and Novartis. Dr. Zarif has received personal compensation for activities with Biogen Idec as a consultant. Ms. Bumstead has received personal compenstion for activities with Biogen Idec and Teva Neuroscience as a consultant. Dr. Fafard has nothing to disclose. Dr. Mebrahtu has nothing to disclose. Dr. Galetta has received personal compensation for activities with Biogen Idec Teva, and Novartis as a speaker.Dr. Galetta has received research support from Biogen Idec. Dr. Doniger has received personal compensation for activities with NeuroTrax Corporation as an employee. Dr. Gudesblatt has received personal compensation for activities with Biogen Idec, Teva Neuroscience, Lundbeck Research USA, Inc. and Medtronic as a consultant.

Optic neuritis (ON) is linked to multiple sclerosis (MS). The presence of white matter lesions on cerebral magnetic resonance imaging (MRI) predicts the risk of MS after ON with considerable accuracy. Oligoclonal bands (OCB) are present in 95 % of MS patients, and a lumbar puncture can also be valuable in the evaluation of patients with ON. We analyzed CSF findings in patients referred with ON in the context of MRI and visual evoked potential (VEP) pathology. We assessed the possible contributory role of a lumbar puncture and weigh this against disadvantages of the procedure. Between February 2003 and November 2011, 505 patients were referred by ophthalmologists to the Clinic of Optic Neuritis, Glostrup Hospital, University of Copenhagen. None had MS prior to referral. A total of 437 were included in the study, and all underwent MRI, a lumbar puncture and VEP. Patients with other organic causes of their symptoms and patients with >3 months between onset and tests were excluded. All files were reviewed retrospectively. CSF leukocytes and the IgG index were elevated in 33 and 41 %, respectively, and OCBs were detected in 61 % of patients. CSF abnormalities correlated strongly with VEP and MRI (p < 0.0001). Patients with normal VEP and MRI had a 96 % probability of a normal lumbar puncture. The contributory role of a lumbar puncture in the evaluation of ON seems negligible when patients have a normal VEP and MRI. We suggest that all patients should be evaluated with VEP and MRI before deciding on a lumbar puncture.

Background: Over the last few years there has been growing interest in use of visual measures as useful tools for multiple sclerosis (MS) prognosis and tracking. Optic neuritis (ON) being a prevalent and often-presenting symptom of the disease, as well as the high occurrence rate of posterior visual system damage independent of ON (optic radiation lesions), make the visual system a prime candidate for such endeavors. However, while the visual system makes for a convenient model in early stages of MS, processes which may be true in those stages may drastically change as the disease progresses, due to accumulated disease load. Here, we examine whether vision-related tools reflect demyelinative and axonal damage of the visual pathways and may be used for assessment in the clinical setup in progressive multiple sclerosis (MS) patients, in whom disease load may alter the early stage picture.Methods: Forty-eight progressive MS patients, with and without prior optic neuritis (ON), underwent a battery of behavioral tests, visual evoked potential (VEP) tests, optical coherence tomography (OCT), and structural MRI scans, at two time-points. Data were analyzed for stability between visits and for correlation between behavioral and electrophysiological data.Results: All measures were stable between visits. Significant differences were found in all measures between the affected and fellow eyes of ON patients and in VEP latencies between the affected and non-ON eyes. Motion perception differentially correlated with latencies of both ON eyes and with the non-ON eyes. Retinal nerve fiber layer thickness correlated with the latencies of non-ON eyes but not of either ON eye. No difference in lesion load was found between the ON and non-ON patients.Conclusions: ON still leaves its mark in the patient's visual system over time, with all visual measures of the affected eyes notably reduced compared to fellow eyes. Motion perception, reflecting myelination level along the visual pathway, shows its usefulness also in progressive MS. In the non-ON eyes, axonal loss appears to explain prolonged latencies, unlike in ON eyes, where demyelination appears to be the main mechanism. Lastly, the visual measures assessed herein are applicable as valid assessment tools in therapeutic studies.

During detailed visual function testing, pattern-reversal visual evoked potentials (VEP), generated by different spatial frequencies (3 c/d, 1 c/d and 0.6 c/d) and visual contrasts (100% and 10%) were recorded in 21 adolescent and young adult phenylketonuric (PKU) patients (11 females and 10 males; mean age 14.8 years, range 9-22.8) on and off diet. In 14 of the 21 patients, disease had been detected at neonatal screening and in 7 later. Ten age-matched healthy subjects acted as controls. Recordings in more than 40% of eyes in the whole group and 30% of eyes in the screening subgroup showed a prolonged P100 latency. All visual pattern stimuli elicited a significantly longer P100 latency in PKU patients than in controls. VEP latencies to 3 c/d, 1 c/d and 1 c/d with 10% contrast--but not to 0.6 c/d--were longer in patients off diet than in patients on diet. No differences were found between VEP latencies in early- and later-detected subjects. To study the link between biochemical variables and VEP latencies, we envisaged either a linear relationship between recent exposure to phenylalanine (Phe) and VEP abnormalities or a threshold model considering phenylalanine (Phe) concentrations among the factors influencing VEP latencies. The correlation analysis detected an association between plasma Phe concentrations and abnormal VEP latencies, predicting that plasma Phe concentrations > 901 mumol/L would prolong VEP latencies to 1 c/d; concentrations > 879 mumol/L would prolong latencies to 3 c/d; and concentrations > 898 mumol/L would prolong latencies to 1 c/d with 10% contrast.

Objective To observe the clinical features and visual function of recurrent neuromyelitis optica (NMO).Methods Thirty-four patients with NMO were enrolled in this retrospective case series study.The patients included two males and 32 females.The average first onset age was (35.03± 14.56) years old and the average recurrent rate were (4.24±2.45) times.The recurrent rate of optic neuritis (ON) ranged from two to 12 times.The recurrent rate of ON was two times in 15 eyes of 10 patients,≥three times in 37 eyes of 24 patients.Vision acuity,direct ophthalmoscope,fundus pre-set lens examination,visual field and visual evoked potential (VEP) were evaluated.Clinical features were observed.The abnormal rate of optic nerve including optic edema and atrophy; abnormal rate of visual field including decreasing retinal sensitivity,central and paracentral scotoma,ring scotoma,half field defects,tunnel visual field,visual field centrality constriction; abnormal rate of VEP including Prolonged latent phase and/or decreasing amplitude of P100 wave from patients of first episode or recurrence was analyzed.Serum NMO-IgG was detected from 28 patients hy indirect immunofluorescence technique to observe its positive rate.Results All patients were characterized by repeated episodes of ON and myelitis.The main clinical feature of ON was visual loss,and the main clinical features of myelitis included sensory disability,dyskinesia and vesicorectal disorder.Blindness rate was 41.67％ after the first attack of ON,33.33％ after two relapses,and 64.86％ after ≥ three relapses.The difference of blindness rate between first attack and two episodes was not significant (x2=0.270,P=0.603).However,the blindness rate in patients having ≥ three episodes was significantly higher than those having two episodes (x2=4.300,P=0.038).With recurrence rate increasing,the abnormal rate of the optic nerve (x2 =6.750,P =0.034) and VEP(x2 =6.990,P =0.030)increased.But the abnormal rate of visual field did not increase along with recurrent rate (x2 =0.660,P=0.718).Seropositive rate of NMO-IgG did not differ significantly between patients with first attack ON and that with recurrent ON (x2 =1.510,P =0.470).But the seropositive patients had significantly higher bilateral blindness rate than seronegative patients (x2=5.063,P=0.027).Conclusions NMO are characterized by recurrent ON and myelitis.Visual loss,sensory disability,dyskinesia and vesicorectal disorder are the main clinical features.With recurrence rate increasing,the blindness rate,abnormalities the optic nerve and the abnormity rate of VEP increase.Seropositive recurrent NMO patients have higher bilateral blindness rate than seronegative patients. Key words: Neuromyelitis optica/diagnosis; Optic neuritis/diagnosis; Vision, binocular; Vision,low; Visual fields

Introduction: Diabetes poses a major health challenge in India, with rising cases leading to serious complications like optic neuropathy and vision loss. These conditions often remain silent in the early stages, making timely detection crucial. Visual Evoked Potentials (VEPs), a simple non-invasive test, offer promise in identifying early optic nerve changes in diabetic patients and may improve outcomes through earlier intervention. Aim: To assess P100 latency and N75-P100 amplitude of VEP as a screening tool for detecting subclinical optic neuropathy in patients with Diabetes Mellitus (DM). Materials and Methods: This hospital-based cross-sectional study was conducted in the Department of Physiology in collaboration with the Department of Medicine at Shaheed Hasan Khan Mewati Government (SHKM) Government Medical College, Nalhar, Nuh, Haryana, India, from November 2022 to October 2023. A total of 240 subjects aged 18 to 60 years were enrolled, comprising 80 individuals with Type 1 Diabetes Mellitus (DM), 80 with Type 2 DM (case group) and 80 non diabetic individuals (control group). Participants were selected using a systematic random sampling method. The VEP test was performed and VEP parameters were compared between the case and control groups. Results: The mean age of the Type 1 DM, Type 2 DM and control groups was 26.61±6.71 years, 43.32±11.09 years and 30.7±11.23 years, respectively. Gender distribution showed that males comprised 53.75% of the Type 1 DM group, 60% of the Type 2 DM group and 70% of the control group. Females accounted for 46.25%, 40% and 30%, respectively. Analysis revealed a significant increase in P100 latency in both Type 1 diabetics (105.30±4.79 msec; p&lt;0.001) and Type 2 diabetics (102.69±6.94 msec; p&lt;0.001) compared with healthy controls. The N75-P100 amplitude was significantly reduced in Type 1 diabetics (5.73±1.98 µV; p=0.04) and Type 2 diabetics (5.87±2.89 µV; p&gt;0.05) compared with controls; however, the difference reached statistical significance only in Type 1 diabetics. Conclusion: This study revealed that P100 latency was prolonged and N75-P100 amplitude was reduced in both Type 1 and Type 2 diabetic patients compared with healthy controls. These results suggest structural changes in the optic nerve, including demyelination and axonal loss. The study recommends incorporating VEP testing into screening protocols for early detection of neurological complications in diabetic patients.

Influence of Cataract Surgery on Optical Coherence Tomography and Neurophysiology Measurements in Patients With Retinitis Pigmentosa

BackgroundMultiple sclerosis (MS) is a common cause of neurological disabilities in adults and commonly affects the visual pathway. The objective of this study is to assess and compare the sensitivity of visual evoked potentials (VEP) and optical coherence tomography (OCT) as measures of early disability in ambulatory patients with MS.MethodsForty-four patients with MS with Expanded Disability Status Scale (EDSS) of ≤ 4.5 (ambulatory patients) and 14 healthy controls participated in this study. Patients were classified into 3 groups according to EDSS. Patients with EDSS of 0–1.5 formed the “No disability,” patients with EDSS of 2–3 formed the “Minimal to mild disability,” and finally patients with EDSS of 3.5–4.5 formed the “Moderate to significant disability” groups. N75/P100 amplitude, P100 latency, retinal nerve fiber layer (RNFL) thickness, and ganglion cell layer complex (GCLC) thickness were measured.ResultsPatients showed significantly lower N75/P100 amplitude, higher P100 latency, lower RNFL, and GCLC thicknesses compared to controls. However, there were non-significant changes in P100 latency, N75/P100 amplitude, and GCLC thickness among the 3 groups for both patients with and without history of optic neuritis (ON). On contrary, RNFL thickness was significantly different between the three groups for both patients with and without history of ON. Factorial ANOVA revealed non-significant disability × History of ON interaction.ConclusionCompared to VEP parameters, RNFL thickness was a sensitive correlate with the various degrees of early disability in fully ambulatory patients with MS whatever the history of ON.

BackgroundThe aim of this study was to investigate potential morphological alterations of gray and white matter in patients with optic neuritis (ON) and their relationship with behavioral performance, using voxel-based morphometry (VBM).Material/MethodsTwelve (4 males, 8 females) patients with ON and 12 (4 males, 8 females) age-, sex-, and education-matched healthy controls (HCs) underwent magnetic resonance imaging (MRI). Imaging data were analyzed using two-sample t tests to identify group differences in gray and white matter volume (GMV, WMV). Correlation analysis was used to explore relationships between observed GMV and WMV of different areas and visual evoked potential (VEP) in ON.ResultsCompared with HCs, ON patients had: significantly decreased GMV in the left postcentral gyrus, left inferior frontal gyrus, left anterior cingulate, left and right middle frontal gyrus, and right inferior parietal lobule; decreased WMV in the left middle frontal gyrus, right superior frontal gyrus, left precentral gyrus and right inferior parietal lobule; and increased WMV in the left fusiform gyrus and left inferior parietal lobule. VEP latency of the right eye in ON correlated positively with WMV signal value of the left fusiform gyrus (r=0.726, p=0.008), and negatively with GMV signal value of the right inferior parietal lobule (r=−0.611, p=0.035). Duration of ON correlated negatively with WMV signal value of the right superior frontal gyrus (r=−0.662, p=0.019), while best-corrected visual acuity (VA) of the right eye correlated negatively with WMV signal value of the left middle frontal gyrus (r=−0.704, p=0.011).ConclusionsThese results suggest significant brain involvement in ON, which may reflect the underlying pathologic mechanism. Correlational results demonstrate that VEP in ON is closely associated with WMV and GMV atrophy in many brain regions.

The pathogenesis of optic neuritis typically involves demyelination, whether or not clinically apparent multiple sclerosis is present. In adults, the overwhelming majority of acute attacks are symptomatic in one eye only. Abnormal visual function in asymptomatic fellow eyes has been reported, though testing has not generally been performed until after resolution of the acute attack,1,2,3,4,5 or only done in patients with clinically evident multiple sclerosis.6,7 Visual function in the fellow eye at the onset of acute unilateral garden variety optic neuritis has not been systematically evaluated. We have previously described the unaffected eyes in 11 patients with acute unilateral optic neuritis.8 Their evaluation revealed deficits on several parameters, despite normal high contrast and low contrast visual acuities. Pelli-Robson contrast sensitivity, S-cone increment thresholds, M-cone increment thresholds and color vision (assessed with the Adams desaturated D-15) were often reduced. Performance on the SKILL card, a low-contrast, low luminance acuity measure, was also abnormal in most of these eyes (73%). We therefore sought to prospectively determine the prevalence of abnormalities in the fellow eyes of the 448 patients enrolled into the Optic Neuritis Treatment Trial (ONTT), a multi-center study which investigated the value of corticosteroids as treatment for optic neuritis. All patients underwent extensive visual function testing in both the affected and unaffected (fellow) eyes.9,10 Data collected on those fellow eyes form the basis for this report.

Visual evoked potentials in children prenatally exposed to methylmercury

To determine the value of electroretinography (ERG) and visual evoked potential (VEP) in predicting visual outcome in patients undergoing osteo-keratoprosthesis (OKP) or osteo-odonto-keratoprosthesis (OOKP) surgery. We performed a retrospective cohort study of 143 eyes in 101 patients who underwent OKP or OOKP surgery. The subjects underwent ERG, VEP testing or both up to 6 months prior to surgery. The ERG and VEP results were classified into four categories based on wave amplitude, latency and configuration. The main outcome was the maximum best-corrected visual acuity (maxBCVA) reached at any time postoperatively. One hundred thirty-four cases had undergone preoperative ERG, 82 VEP and 73 both examinations. The sensitivities of ERG and VEP to detect maxBCVA≥0.05 were 68.5% and 87%, respectively, while the specificity was 63.2% for ERG and 47.4% for VEP. The maxBCVA was significantly better in patients with normal ERG (p=0.033) and those with normal VEP (p=0.048), once having defined appropriate normal and abnormal cut-off levels. When comparing fellow eyes in patients who underwent surgery in both eyes, maxBCVA was better in the eyes that had better VEP results (p=0.013). Eyes demonstrating normal ERG or VEP achieved better visual outcome than those with abnormal results. In addition, VEP proved instrumental in determining the eye with the best prognosis when comparing both eyes of a given patient.

P-EV002. Visual evoked potentials in neuromyelitis optica spectrum disorders

Purpose:Visual evoked potentials (VEP) are used to determine the function of visual pathway from the optic nerve to visual cortex. Various factors may affect VEP response, viz., technical and environmental. The aim of this study is to obtain the normative value of VEP latency and amplitude parameters in adulthood in Indonesia, as well as the relationship of height, weight, body mass index (BMI), head circumference, and visual acuity with the variety of latency and amplitude values of VEP parameters.Methods:It is a cross-sectional study on 120 healthy subjects consisting of 60 males and 60 females between 18 and 65 years old. Height, weight, BMI, head circumference, and visual acuity were measured and continued with VEP examination using a 26′ checkerboard pattern on the left and right eyes alternately. All data were collected and analyzed with the Shapiro–Wilk test using statistical software R version 3.5.2.Results:Mean value of P100 latency (interocular latency) of left and right eye were 104.6 ± 3.4 ms and 104.1 ± 3.4 ms, respectively, as well as 9.8 ± 4.7 μV and 10.3 ± 5.4 μV for the amplitude. There was no significant difference between the male and female group, as well as on the age group. Female significantly exhibited a higher P100 amplitude than male. The greater the age, the lower amplitude of P100 significantly.Conclusion:Gender and age do not affect the P100 latency value but only affect P100 amplitude. Height, weight, BMI, head circumference, and visual acuity also do not affect the P100 latency and amplitude.