Electrogustometric examinations in cerebellopontine tumors and on taste pathways

Abstract

A description of an electrogustometric technic for the determination of taste thresholds is given. The method would appear to be reliable and well suited for clinical use. The results are more reliable and more accurate than those obtained from a semiquantitative method involving the use of test solutions. A purely qualitative technic using highly concentrated test solutions obviously can only give rough and, in many cases, misleading estimates of gustatory changes. The writer, therefore, is of the opinion that this method should no longer have its place in neurologic diagnostics when technics for investigations of the functions of the other cranial nerves have been improved to existing standards. Gustatory investigations belong to the otoneurologist since a careful otoscopy is essential for a well performed gustatory investigation. On the basis of the clinical findings of tumors in the cerebellopontine angle and the subsequent discussion on earlier works on the course of the taste pathways, it would seem reasonable to assume that the taste fibers from the anterior part of the tongue, in all cases, take the following course: lingual nerve, chorda tympani, facial nerve, intermedius of Wrisberg. This is in complete agreement with the observations made by Cushing and Dandy 55 and 28 years ago, respectively.