Abstract
Electrogustometry is a simple electrodiagnostic procedure to examine disorders of gustatory function and pathway and now widely accepted in the clinical practice as a testing method giving a relatively reliable and accurate functional information, although this test itself still has some theoretical and practical problems to be solved.
Gustometry using several taste substances, on the other hand, has been of little value in determining gustatory function and pathway because of poor accuracy in quantitative aspect and of insufficient selectivity to examine gustatory innervation, whatever the testing procedures used.
We have recently developed a qualitative and quantitative gustometric testing method using the filter paper disc of an uniform size which was immersed in several taste substances with various concentrations, and called this procedure as “filter paper disc method ”.
It is the purpose of this paper to study the correlation between the thresholds of quantitative gustometry with “filter paper disc method” and those of electrogustometry. The results obtained in this study were as follows.
1) Threshold elevation in the gustometric measuring with aging was noted in all the three innervated areas in the normal subjects. Among the areas, the threshold elevation with aging was evidently demonstrated in the area innervated by the greater superficial petrosal nerve and therefore the elevated thresholds of the aged individuals in this area were not directly accounted for abnormal or pathologic findings.
2) The thresholds of electrogustometric measurements were, in general, well correlated with those of “filter paper disc method ”, although there was some gap or discrepancy between the values obtained by these two procedures, which might possibly be due to the difference in gustatory perception mechanism.
3) Electrogustometric testing and “filter paper disc method” were applied to examine gustatory function of the patients with facial palsy. As a result of this comparative study, the threshold elevation in the electrogustometric measurement was also generally proportional to the extent of impairment of the responses to all the four taste substances.
It might be reasonable to conclude from these data that a quantitative gustometric method using several taste substances (“filter paper disc method ”) could also be basically useful for the correct diagnoses of gustatory dysfunction and the related disorders together with electrogustometric measurement.
