Visual evoked potentials’ responses in hypothyroidism and hyperthyroidism

Background: Visual Evoked Potentials (VEP) provides important diagnostic and prognostic information regarding the functional integrity of the visual system. This study, describes the effects of less or excess thyroid hormones of adults in visual conduction that helps to know the progression to neurological functional defects.Methods: The study was done in 75 consenting subjects (hypothyroid = 24, hyperthyroid = 25, euthyroid = 26). The VEP parameters N75, P100, N145 latencies and its amplitudes within different thyroid status (hypothyroidism, hyperthyroidism and euthyroidism) were compared. One way ANOVA was used to compare VEP parameters among three groups and Pearson’s correlation to find relation between thyroid hormones and VEP parameters.Results: There was positive correlation of 0.335, 0.338 and 0.301 between amplitudes of N75, P100 and N145 waves and fT3 hormone respectively. Furthermore, fT4 showed a positive correlation of 0.186 and 0.185 with the wave amplitudes of N75 and N145 waves respectively and negative correlation of TSH levels of -0.492, -0.280, -0.397 with amplitudes of N75, P100, N145 waves respectively. Hyperthyroid group had higher in VEP latency than euthyroid group in N75 (73±5.77 vs. 68.54±4.32), P100 (106.42±9.74 vs. 100.94±8.17) and N145 (153.03±16.39 vs. 144.37±7.02) waves. Similarly, hypothyroid group had higher in VEP latency than euthyroid group in N75 (72.12±6.34 vs. 68.54±4.32) wave.Conclusions: Both hypothyroidism and hyperthyroidism led to conduction delay in adults, possibly adversely affecting function of myelin. The prominent visual evoked potential abnormalities in hyperthyroidism and less change in hypothyroidism show that the visual neuropathy is more common in hyperthyroidism.

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Pattern Electroretinography and Visual Evoked Potentials Provide Clinical Evidence of CNS Modulation of High- and Low-Contrast VEP Latency in Glaucoma

Translational Vision Science & Technology ◽

10.1167/tvst.6.6.6 ◽

2017 ◽

Vol 6 (6) ◽

pp. 6 ◽

Cited By ~ 4

Author(s):

William E. Sponsel ◽

Susan L. Johnson ◽

Rick Trevino ◽

Alberto Gonzalez ◽

Sylvia L. Groth ◽

...

Keyword(s):

Evoked Potentials ◽

Visual Evoked Potentials ◽

Clinical Evidence ◽

Low Contrast ◽

Pattern Electroretinography ◽

Vep Latency ◽

Visual Evoked

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Gender based normative values of pattern-reversal visual evoked potentials in school age children

International Journal of Biomedical Research ◽

10.7439/ijbr.v9i5.4759 ◽

2018 ◽

Vol 9 (5) ◽

pp. 175

Author(s):

Sanjay Maharjan ◽

Rita Khadka ◽

Bishnu Hari Poudel ◽

Nisha Ghimire ◽

Kopila Agrawal ◽

...

Keyword(s):

Evoked Potentials ◽

Visual Evoked Potentials ◽

Cross Sectional Study ◽

School Age Children ◽

Normative Values ◽

Pattern Reversal ◽

Cross Sectional ◽

Biological Variables ◽

Vep Latency ◽

Visual Evoked

Background: Male and female brain develops differently. Gender is one of biological variables that influence visual evoked potentials (VEP). Some previous studies support the existence of sex related VEP difference while others not. This study is an attempt to explore if any difference exists in VEP responses between genders of children age seven to 10 years with an additional aim of documenting preliminary normative VEP data.Methods: This cross-sectional study was done on consenting children taken from parents (n=76; girls, n=41, age = 8.39±1.11years; boys, n=35, age =8.40±1.09 years). Pattern reversal VEP of these children was recorded as per standard method. Latencies of N75, P100, and N145 (ms); amplitude of P100 (μV) and ratio; interocular asymmetry (ms) of both eyes were calculated. Unpaired t-test was applied for statistical analysis. Ethical clearance was obtained prior to the study. Result: Girls had decreased VEP latency of P100 than boys in left eye (108.15±8.42 vs. 112.71±11.17ms, p = 0.046), in right eye (107.71±8.52 vs. 114.46±10.98 ms, p = 0.004), and in combination of both eyes (107.92±8.07 vs. 113.58±10.36 ms, p = 0.009). Likewise, girls had decreased VEP latency of N75 than boys in right eye (67.44±6.77 vs. 71.29±8.07 ms, p = 0.027) and in combined eyes (67.23±5.19 vs. 70.14±7.31 ms, p = 0.047). A gender difference in P100 amplitude was not detected.Conclusion: Visual evoked potential differs with gender in prepubertal children aged seven to 10 years.

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Pattern reversal visual evoked potentials as a measure of visual pathway pathology in multiple sclerosis

Multiple Sclerosis Journal ◽

10.1191/1352458503ms935rr ◽

2003 ◽

Vol 9 (5) ◽

pp. 529-534 ◽

Cited By ~ 47

Author(s):

B Weinstock-Guttman ◽

M Baier ◽

R Stockton ◽

A Weinstock ◽

T Justinger ◽

...

Keyword(s):

Multiple Sclerosis ◽

Evoked Potentials ◽

Visual Evoked Potentials ◽

Amplitude Ratio ◽

Phase Iii ◽

Pattern Reversal ◽

Prognostic Information ◽

Mri Scans ◽

Visual Evoked

Background: Pattern reversal visual evoked potentials (PRVEPs) have a well-documented role in diagnosis of multiple sclerosis (MS), but their value as a visual function surrogate remains controversial. Methods: We evaluated PRVEP in 37 patients with MS who were participating in a long-term follow-up study following a phase III trial of interferon b-1a (A vonex®). Patients were examined to determine the Kurtzke Extended Disability Status Score (EDSS), multiple sclerosis functional composite (MSFC), contrast letter acuity (CLA), and had cranial MRI scans to determine whole brain atrophy (BPF). PRVEP was evaluated for P100 latency, amplitude, and waveform morphology. Two summary scores were created: for Score A, abnormal latencies, morphologies, and amplitudes of each individual eye were added; for Score B, abnormal latencies, morphologies, and amplitude ratio between eyes was determined. Sixteen patients in this group also had PRVEP at the time they enrolled in the clinical trial, eight years previously. Results: A t the follow-up exam, over 75% of patients had abnormal PVEP parameters while visual acuity (VA) was abnormal only in 59%. Increased PRVEP latency over the eight-year period correlated with deterioration assessed by EDSS (P = 0.006), BPF (P = 0.0001), and MSFC (P = 0.0041). Score A was significantly correlated with EDSS, BPF, C LA, cognitive function, and quality of life assessed with the Sickness Impact profile. No correlation was seen with the MSFC. Conclusions: The results indicate that PRVEP measures MS-related patho logy, and can provide not only diagnostic but also prognostic information during evaluation of MS patients.

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