相互相関関数法による聴性脳幹反応の解析 脊髄小脳変性症と多発性硬化症における検討

Abstract

The diagnostic usefulness of cross correlation function in the analysis of auditory brain stem responses (ABR) in Spinocerebellar degeneration (SCD) and multiple sclerosis (MS) was evaluated. ABR recordings from 30 normal males and females were averaged to produce normative ABR waveforms serving as templates for each gender. The cross correlation function between the individual ABR recording and the corresponding template was calculated, yielding an objective measure of the ABR waveform and gross latency. Cross correlation indexes were: RU (Correlation Coefficient at time O), RM (Maximal Correlation Coefficient) and DL (Latency Delay in msec).In 22 patients with SCD with pontine atrophy diagnosed by CT scan, abnormalities of cross correlation function were detected more frequently (81.8%) than abnormalities of ABR peak latency (68.2% according to traditional criteria and 77.3% according to the criteria for each gender).The evaluation of ABR waveform characteristics with cross correlation function using normative ABRs of the same gender were demonstrated to contribute to the diagnosis of slight lesions in the brain stem auditory pathway.