The PRVEPs evoked by different fields stimulation / 法医学杂志

OBJECTIVE@#To study the character of the PRVEPs evoked by different stimulation fields in normal-vision subjects and its value in forensic medicine.@*METHODS@#The PRVEPs were evoked by full-field, central-field and peripheral-field respectively in 30 subjects (60 eyes) and the latency and amplitude of N1 and P1 were analyzed.@*RESULTS@#There was no statistically significant difference in the latency and amplitude of PRVEPs between right and left eyes. The appearance probability of all the waves was 100% at the different stimulations but that of N1 was 36.77% at the central-field. There was statistically significant difference in the latency of N1 at the full field and peripheral field stimulations and there was no statistically significant difference in the amplitude. There was statistically significant difference in the latency and amplitude of P1 at the full field, central field and peripheral field stimulation.@*CONCLUSION@#The PRVEPs evoked by different field stimulations can be used to evaluate the functions of the different area retina and can be used to identify the exaggerated or pretended visual dysfunction.

The application of the same frequency tone masking test in forensic identification / 法医学杂志

OBJECTIVE@#To investigate the relationship between minimum contralateral masking level (MCML) and pure tone threshold of the masking ears by the same frequency tone masking test.@*METHODS@#The pure tone thresholds of 30 subjects (60 ears) were measured by pure tone audiometry and MCML was obtained by means of the same frequency tone masking test.@*RESULTS@#When the stimulus was at the threshold of masked ears, the differences between MCML and pure tone threshold of masking ears were among 0-30 dBHL. 82.4 percent of results showed the differences not higher than 10 dBHL, 97.1 percent of results showed the differences not higher than 15 dBHL. When the stimulus was at 10 dBHL above the threshold of masked ears, the differences between MCML and pure tone threshold of masking ears were among 0-35 dBHL. 90.5 percent of results showed the differences not higher than 25 dBHL, 98.1 percent of results showed the differences not higher than 30 dBHL.@*CONCLUSION@#The real thresholds can be deduced correctly by the same frequency tone masking test.