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Singh, Ramji
- Influence of Refractory Error on the Pattern Reversal VEPs of Myopes and Hypermetropes
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Authors
Affiliations
1 Assistant Professor, Dept. of Physiology, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha Maharashtra
2 Assistant Professor, Dept. of Anatomy. Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha Maharashtra
3 Professor, Dept. of Physiology, AIIMS, Patna, Bihar
4 Professor, Dept. of Ophthalmology, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha Maharashtra
1 Assistant Professor, Dept. of Physiology, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha Maharashtra
2 Assistant Professor, Dept. of Anatomy. Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha Maharashtra
3 Professor, Dept. of Physiology, AIIMS, Patna, Bihar
4 Professor, Dept. of Ophthalmology, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha Maharashtra
Source
International Journal of Physiology, Vol 1, No 1 (2013), Pagination: 57-61Abstract
Objective: Multiple factors including age, sex, habituation, refraction, cooperation and technical variables are associated with Visual evoked potential (VEP). We attempted to evaluate the influence of refractory error on the Pattern Reversal Visual Evoked Potential (PRVEP) recordings of a cohort of Indian subjects having myopia and hypermetropia.
Material: This rural hospital based study was conducted in the Neurophysiology unit of the Department of Physiology. The study comprised of pattern reversal visual evoked potential (PRVEP) recordings from 50 hypermetropes and 50 myopes with and without glasses having age in the range of 18-40 years. The recordings were compared with those of 50 age and sex matched controls.
Methods: One channel VEP recordings were performed with the stimulus configuration consisting of the transient pattern reversal method in which a black and white checker board was generated (full field) and displayed on VEP Monitor (colour 14") by an electronic pattern regenerator inbuilt in an Evoked Potential Recorder (RMS EMG EP MARK II). P100 latency and amplitude were measured from the averaged waveforms and analysed by student's "t" test.
Results: P100 latency was increased and amplitude decreased with and without correction of refractive error. The statistical analysis revealed a significant difference (p<0.05) in latency of P100 and amplitude of P100 between controls and myopics with glasses and highly significant difference (p<0.001) in latency and amplitude of P100 between controls and myopics without glasses. The difference in P100 latency and amplitude between controls and hyperopics with glasses and those without glasses were found to be non-significant.
Conclusion: VEPs are affected in subjects with refractive error irrespective of correction given. Among the refractory errors, the VEPs seem to be more affected by myopia than hypermetropia and the probable contributory cause may be the defocusing of the image.
Keywords
Refractive Error,Hypermetropes, Myopes, P100 Latency, P100 Amplitude
References
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- Sleep Habits in First Year Medical Students at AIIMS Patna and its Impact on their Academic Performance
Abstract Views :504 |
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Authors
Affiliations
1 Department of Physiology AIIMS Patna, IN
1 Department of Physiology AIIMS Patna, IN
Source
International Journal of Physiology, Vol 8, No 1 (2020), Pagination: 124-129Abstract
Introduction: - Sleep is an important biological necessity. Sleep timing and duration affects many functions of our body like, endocrine, metabolic, and neurological functions which are critical to the maintenance of individual health. College students often have erratic sleep schedules, poor sleep hygiene and poor sleep quality, which might affect their performance and cognitive functions. Objective: To characterize sleep habits and day and night habits in medical students using sleep quality assessment (PQSI scale) and Epworth sleepiness scale; to estimate how subjective sleep quality is associated with sleep problems in students; to estimate how academic progress is associated with subjective sleep quality. Materials and Method: A cross-sectional design- A self-administered paper questionnaire was administered of first-year through finalyear MBBS students. Students data on sleep quality was collected routinely as part of orientation program to assess students’ need in department of Physiology. Data on academic performance (first professional marks) was accessed from examination controller. Pittsburgh sleep quality index and Epworth sleepiness scale scoring was done. Results: A total of 90 medical students of AIIMS Patna, aged 16 to 25 years completed the study. Sleep habits of students shows an extreme range of 2 to 4 hrs minimum sleep to 7 to 9 hrs of maximum sleep. Maximum students take 6 to 7 hrs sleep. No statistically significant difference in academic performance between the different Epworth sleepiness score is observed. Negative correlation was obtained between the PSQI and grade average.Keywords
Sleep Deprivation, Academic Performance, ESS Score, Global PQSI.References
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