كليدواژه :
پزشكي , بيماريهاي دستگاه عصبي , پتانسيل برانگيخته بينايي , Nervous System Diseases , Evoked Potential , Visual
چكيده لاتين :
Introduction: VEP is a diagnostic test, especially for multiple sclerosis and optic neuritis.
Objective: This survey was carried out to determine the influence of age, sex, dominant eye and technical factor on the mean P100 latency values of VEP in Rasht Poorsina Hospital.
Materials and Methods: 66 females (18-65 years old) and 66 males (18-65 years old) who had specific
characteristics of normal subjects, were selected.
Visual stimulation was given by Medelec monitor 25004, with visual angle 15 degree. After 118 stimuli to each
eye separately, with frequency of 2HZ,. the results were registered.
The collected data were analysed with spss software and t-test and variance analysis and post Hoc method were used for evaluation of mean value differences. The significance level was 0.05.
Results: Mean p100 latency was 100.75±6.99 msec in all, 99.64±6.56 msec in females and 101.86±7.24 msec in
males (P=0.01)
Mean P100 latency was 100.73±6.7 msec in right eyes and 100.77±7.2 msec in left eyes, and 100.75 msec in all
(P=0.959).
Interocular P100 latency difference was 2,4±2.2 msec in all persons, 2.2±2.4 in females and 2.6±1.9 in males
(P=0.041)
Mean P100 latency was 97.96±10.1 in subjects less than 20 years old and 101.65±7.41 ms in 20-30 years old and
99.97±6.65 msec in 30-40 years old and 100.41±6.01 msec in 40-50 years old and 101.01±6.76 msec in 50-60
years and 107.17±4.95 ms in >60 years old. (P=0.004)
Conclusion: In spite of the maximum mean P100 latency in our study subjects which was in normal range, mean P100 latency in each sex and mean P100 latency difference between two eyes and mean P100 latency in 60-65 years old were significantly different from reference books. Thus, we recommend that for precise interpretation of electrophysiologic data, each laboratory should obtain and use its normal values separately.
