Electrogustometric examinations in cerebellopontine tumors and on taste pathways
Electrogustometric examinations in cerebellopontine tumors and on taste pathways
复制标题
小脑桥脑肿瘤和味觉通路的味觉检查
作者：
Bent Krarup
SINCE THE TIME of Magendiel and Lussana,2 the problem of the course of the taste pathways from the anterior part of the tongue has given rise to speculations as to the part played by the facial and trigeminal nerves, as well as the anastomoses between them, as conductors of taste impulses. It is now generally accepted that the msst frequent pathway takes the following course lingual nerve, chorda tympani, facial nerve, intermedius of Wrisberg3.4 -but many textbooks on anatomy, physiology, and neurology5-”3 describe as many as 5 alternative pathways for taste impulses. For this reason, neurologists have not paid greater attention to clinical taste examinations; pathologic findings do not yield reliable information on the localization of an eventual lesion of the pathways. From the relevant literature, the varying opinions on the course of the taste fibers of the fifth and seventh cranial nerves show that the conclusions are very largely based on investigations camed out on patients with nerve lesions caused by neurosurgical operations or injections. Because several investigators have obtained widely diverging results in examinations of patients of the same category, it was of interest to inquire into the cause of these variances. The explanation would appear to be governed by [ 11 the close anatomic relationship between the fifth and seventh cranial nerves, making it exceedingly complicated to exclude simultaneous lesions of both nerves and therefore equally difficult to select the clinical material, and [2] the employment of too coarse a technic in the taste examinations. No one has described this problem more clearly than Cushingll who, in his book on acoustic tumors, writes: “Unless the tests for the cardinal taste qualities are made with full appreciation of the difficulty of interpreting gustatory impulses, when common sensation of the tongue is affected, errors may easily be made.” It was desirable, therefore, to develop a new technic for gustatory experiments. The method had to be [l] quantitative, thus enabling finer changes to be diagnosed; [2] applicable to a desired area, so that the stimulus could be directed to one part of the tongue without risk of involving other tongue areas; [3] such that a stimulation of the receptors of the sense of taste could not be mistaken for a stimulation of those for common sensation; [4] applicable to as large a number of patients as possible with a minimum demand on the patient’s perception and cooperation; and [ 5 ] simple and quick, making it practical as a routine clinical investigation. This paper will describe an electrogustometric technic that appears to fulfill the above demands. It is based on the phenomenon that an electric current passed through the tongue creates a taste impulse of an acid, metallic character. Volta has already demonstrated such a reaction and Hofmann and Bunzel,12 Hermann,ls Ohrwall,14 and Bujas and Chweitzer15 have all written on th is subject. That a galvanic stimulus can be used in clinical tials is mentioned by DeJong3 and
