scholarly journals Impact of Spectral Severity of Alcoholism on Visual-Evoked Potentials: A Neuropsychiatric Perspective

2018 ◽  
Vol 09 (03) ◽  
pp. 381-390
Author(s):  
Ruchi Kothari ◽  
Praveen Khairkar ◽  
Sneh Babhulkar ◽  
Pradeep Bokariya

ABSTRACT Background: The deleterious effects of alcohol on the brain are replete in literature. Only a few neurophysiologic measures can pick up the neuronal dysfunctions, one of them being visual-evoked potential (VEP). A very limited amount of data exists on the progression of neural abnormalities related to the spectral severity of alcoholism. Aim of the Study: To evaluate the impact of spectral severity of alcoholism through VEP and to understand the emergence of any specific pattern or morphometric abnormalities related to alcohol-induced neuropsychiatric presentations. Methodology: A total of 90 cases were recruited in addition to 180 age- and sex-matched controls using purposive and random sampling. The Structured Clinical Interview for DSM-IV Axis I Disorders, Clinician Version and Campbell Neuropsychiatric Inventory were used to evaluate alcohol disorders and its neuropsychiatric complications apart from the mandatory consultant-specific clinical evaluations of all the cases. Of 90 cases of alcohol dependence, 15 patients were currently abstinent for >6 months, 15 had alcohol intoxication, 15 had signs of alcohol withdrawal, 15 had physical complications, 15 had psychiatric comorbidity, and 15 had neurological complications such as epilepsy. VEP recordings were taken using an Evoked Potential Recorder (RMS EMG. EP MARK II) where the stimulus configuration consisted of transient pattern-reversal method in which a black and white checkerboard was generated full field. Results: Mean age of cases was 37.71 ± 11.49 years compared to 39.43 ± 10.67 years in controls (range 18–65 years). VEP abnormalities comprising of prolonged latencies (62.5%) with a statistically significant difference (P < 0.001) from the healthy controls was observed in cases of alcohol withdrawal syndrome. Predominant amplitude reduction with normal latency was obtained in 37.5% cases of withdrawal. Severe VEP abnormalities, i.e., both latency delay and amplitude reduction, were found in 75% patients with psychiatric comorbidity, 66.67% patients with neurological complications, i.e., epilepsy, and 33.34% patients with physical complications. An explicit finding of prominent interocular differences was a prominent feature present in 25% of patients with complications.

2016 ◽  
Vol 07 (S 01) ◽  
pp. S046-S051
Author(s):  
Pooja Jaiswal ◽  
Yogesh Saxena ◽  
Rani Gupta ◽  
Rajeev Mohan Kaushik

ABSTRACT Background: Central nervous system (CNS) involvement is insidious and may occur early in subclinical hypothyroid (SCH) state which can be picked up by electrophysiological study. This study aims to record visual evoked potential (VEP), event-related latency and cognitive functions, and find their association with the levels of serum thyroid-stimulating hormone (TSH) in patients with SCH. Materials and Methods: In this cross-sectional study, 36 adult SCH patients and an equal number of age- and sex-matched euthyroid controls were included. Pattern reversal VEP, visual reaction time (RT), digit spanning test, and AB clock test (ABCT) were done in both SCH cases and euthyroid controls. The observed values were analyzed for comparison of mean values between the groups and correlation of recorded variables with the levels of serum TSH. Results: SCH cases showed a higher P100 (VEP) latency in both the right (103.2 ± 12.3 vs. 102.7 ± 6.8 ms) and left eye (101.1 ± 9.1 vs. 96.2 ± 10.7 ms) as compared to controls, but the difference was statistically insignificant. A significant delay in RT was observed on visible spectra of light in SCH cases (P < 0.001). Digit spanning score (forward and backward) in SCH cases was significantly lower than controls (P < 0.001), and a lower standardized score (<124 or <95th percentile) was significantly associated with SCH state (P = 0.027). No significant difference was observed in visuospatial domain by ABCT between both the groups although the median score was lower in SCH cases. Only digit spanning score showed a significant negative correlation with TSH levels (r = −0.4; P = 0.001). Conclusion: Decline in working memory and RT to visual stimuli is an evidence of the involvement of CNS in SCH. Prolonged latency in VEP may depend on the duration of SCH.


Author(s):  
Homa Hassankarimi ◽  
Ebrahim Jafarzadehpur ◽  
Alireza Mohammadi ◽  
Seyed Mohammad Reza Noori

Purpose: To evaluate the pattern-reversal visual evoked potential (PRVEP) in lowcontrast, spatial frequencies in time, frequency, and time-frequency domains. Methods: PRVEP was performed in 31 normal eyes, according to the International Society of Electrophysiology of Vision (ISCEV) protocol. Test stimuli had checkerboard of 5% contrast with spatial frequencies of 1, 2, and 4 cycles per degree (cpd). For each VEP waveform, the time domain (TD) analysis, Fast Fourier Transform(FFT), and discrete wavelet transform (DWT) were performed using MATLAB software. The VEP component changes as a function of spatial frequency (SF) were compared among time, frequency, and time–frequency dimensions. Results: As a consequence of increased SF, a significant attenuation of the P100 amplitude and prolongation of P100 latency were seen, while there was no significant difference in frequency components. In the wavelet domain, an increase in SF at a contrast level of 5% enhanced DWT coefficients. However, this increase had no meaningful effect on the 7P descriptor. Conclusion: At a low contrast level of 5%, SF-dependent changes in PRVEP parameters can be better identified with the TD and DWT approaches compared to the Fourier approach. However, specific visual processing may be seen with the wavelet transform.


2015 ◽  
Vol 8 (2) ◽  
pp. 2106-2121
Author(s):  
Hamed Ibrahem Abdelkader ◽  
Mona Abdelkader ◽  
Mohammed Kabeel ◽  
Malak Alya

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  in the age of 25-50 years.  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  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  the two groups.  


1985 ◽  
Vol 147 (5) ◽  
pp. 532-539 ◽  
Author(s):  
Graham F. A. Harding ◽  
Christine E. Wright ◽  
Arnold Orwin

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.


2021 ◽  
Vol 58 (2) ◽  
pp. 78-83
Author(s):  
Luan F. B. Almeida ◽  
Marisa Kattah ◽  
Liana O. Ventura ◽  
Adriana L. Gois ◽  
Camilla Rocha ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Taylor A. Nichols ◽  
Sophie Robert ◽  
David J. Taber ◽  
Jeffrey Cluver

Abstract Introduction Limited evidence exists evaluating the impact of gabapentin in conjunction with benzodiazepines for the management of alcohol withdrawal. A review of outcomes associated with combination gabapentin and benzodiazepine therapy may illuminate new therapeutic uses in clinical practice. Methods This retrospective study evaluated the impact of gabapentin on as-needed use of benzodiazepines in inpatients being treated for acute alcohol withdrawal. The treatment cohort consisted of patients prescribed gabapentin while on a symptom-triggered alcohol withdrawal protocol. The control cohort consisted of patients on symptom-triggered alcohol withdrawal protocol without concurrent gabapentin use. Secondary objectives included length of hospital stay, duration on alcohol withdrawal protocol, frequency of complicated withdrawal, and use of additionally prescribed as-needed or scheduled benzodiazepines. Results The gabapentin cohort was on the alcohol withdrawal protocol for a similar duration, compared with the control cohort (median of 4 [interquartile range: 2,6] days vs 3 [2,4] days, P = .09, respectively). Similarly, the gabapentin cohort required a median of 1 [1,2] benzodiazepine dose for alcohol withdrawal symptoms compared with a median of 1 [1,2] dose in the control cohort, P = .89. No significant difference was found between cohorts for as-needed and scheduled benzodiazepine use. Length of stay in hospital was similar between groups. Discussion These results suggest that gabapentin use, in conjunction with benzodiazepines, impacts neither the time on alcohol withdrawal protocol or the number of benzodiazepine doses required for withdrawal. Larger, prospective studies are needed to detect if gabapentin alters benzodiazepine usage and to better elucidate gabapentin's role in acute alcohol withdrawal.


2020 ◽  
Vol 24 (1) ◽  
pp. 226-234 ◽  
Author(s):  
Rossana Terracciano ◽  
Alessandro Sanginario ◽  
Simona Barbero ◽  
Davide Putignano ◽  
Lorenzo Canavese ◽  
...  

2020 ◽  
Vol 11 (2) ◽  
pp. 9-13
Author(s):  
Karishma Rajbhandari Pandey ◽  
Dipesh Raj Panday ◽  
Nirmala Limbu ◽  
Bhupendra Shah ◽  
Kopila Agarwal

Background: Nicotine in tobacco smoke causes demyelination. Again, hypoxia in long-term smokers is linked to neuropathy. Visual receptors are early sufferer of neuropathy. Visual-Acuity & other ocular tests often fail to detect subtle changes of neuropathy which, however, can be detected by VEP test. Literature review shows that changes in VEP come earlier than PFT changes in smokers. Ironically, smokers claim that smoking improves their reaction time, which can be assessed by VRT. Aims and Objective: To relate smoking status with VEP and VRT. Materials and Methods: Fifty-six subjects (smoker group = 28 & non-smoker group = 28), whose age & sex were matched, were included in the study. Their PFT, pattern VEP of both eyes & VRT were recorded. The data were compared between the two groups using unpaired t-test, considering statistical significance at p<0.05. Results: The FVC (4.35±0.83 vs. 5.32+1.18 l, p=0.022), FEF 25% (7.40+2.38 vs. 8.74+3.90 l/s, p=0.019) & FEF 50% (6.11+1.52 vs. 7.74+2.57, p= 0.010) were significantly lower in smokers compared to nonsmokers. There was no significant difference in P100 wave latency of VEP. But, VRT of smokers were significantly shorter (431.69+60.29 vs. 441.14+123.54 ms, p=0.010). Conclusion: Smokers have shorter visual reaction time and similar visual evoked potential as compared to non-smokers.


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