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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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Background: Nerve conduction study (NCS) is useful for evaluation of nerve, muscle, and/or neuromuscular function. Neurophysiologist interprets NCS with consideration of various anthropometric and technical parameters viz. age, gender, height, temperature etc. apart from the underlying pathology. Fewer studies have reported the effect of limb dominance on NCS. Moreover, the findings are controversial. Therefore, author aimed to investigate the effect of limb dominance on motor nerve conduction study parameters.Methods: This cross-sectional comparative study included sixty healthy individuals (44 right and 16 left handed) of either sex with age 18 to 30 years. The NCS parameters of median and ulnar nerves were assessed by stimulating it and recording from the muscle and skin overlying the nerve respectively using Digital Nihon Kohden machine. The obtained data were analyzed using independent sample t-test.Results: Right ulnar nerve onset latency was significantly longer in left-handed individuals (1.85±0.508 ms vs 1.62±0.195 ms, p=0.012). The left ulnar nerve F wave minimum latency (25.88±0.74 ms vs 24.46±2.64 ms, p=0.002) was significantly longer in left-handed individuals. Likewise, right ulnar nerve distal latency (2.45±0.76 ms vs 2.14±0.39 ms, p=0.044), and right ulnar nerve F wave minimum (25.9±1.21 ms vs 24.85 ms±1.74, p=0.030) were significantly high in left-handed individuals.Conclusions: NCS parameters in terms of latencies were longer in left-handed individuals. Therefore, limb dominance seems to be an important factor one should pay attention during bilateral comparison of obtained data in neurophysiological reporting of referred cases.
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Background and Objective: Clinical trials have shown the potential use of 5-HT3 receptor antagonists like Ondansetron, Tropisetron and Zacopride in a number of disorders of gastrointestinal tract and the central nervous system such as cancer chemotherapy induced vomiting, anxiety, depression, schizophrenia and migraine. Various experimental and clinical studies also point the usefulness of Ondansetron in neuropathic pain. Therefore, the present study was conducted to find out whether Ondansetron could be used as an alternative to a standard drug, Amitriptyline in the treatment of peripheral neuropathy. Methodology: A randomized double blind prospective clinical study was conducted on Original Research Article British Journal of Medicine & Medical Research, 4(26): 4444-4454, 2014 4445 thirty six patients of peripheral neuropathy divided into two groups of equal number of patients. Group 1 received Ondansetron 8 mg per day while Group 2 received Amitriptyline 25 mg per day. Patients were being evaluated on the basis of improvements (decrease) in LANSS (Leeds Assessment of Neuropathic Symptoms and Signs), VAS (Visual Analogue Scale) and NCV (Nerve Conduction Velocity) for six weeks. Student’s ttest and/or repeated measure ANOVA followed by Bonferoni correlation was used to compare sets of paired observations. The Friedman test followed by multiple comparisons was used to compare the data which was not normally distributed. Results: LANSS and VAS scores showed significant improvements in the 1st and 2nd visit in both the groups. NCV showed improvement in Ondansetron group with less number of adverse effects compared to that of Amitriptyline. NCV in Amitriptyline group demonstrated significant increase in one of the parameters, F-waves, indicating a worsening in left tibial nerve (p=0.036), whereas no such change was found in the group treated with Ondansetron. Conclusion: Ondansetron has beneficial role in peripheral neuropathy by improving its sensory component as it significantly decreased LANSS and VAS scores. Our results also demonstrated that Ondansetron was at least as efficacious as Amitriptyline in the treatment of peripheral neuropathy with lesser adverse effects.