GUSTATORY FUNCTION MEASURED BY ELECTROGUSTOMETRY AND FILTER-PAPER DISK METHOD IN MDDLE EAR DISEASES
Sone M, Seo T, Fukazawa K, Node M, Sakagami M
Dept. of Otolaryngology, Hyogo College of Medicine, Nishimomiya, Hyogo, Japan
It is well known that chorda tympani nerve (CTN) is frequently damaged in inflammatory middle ear diseases and gustatory function becomes worse. However, there have been comparatively few studies of changes in taste and gustatory function resulting from middle ear diseases. In the present study, electrogustometry EGM) and filter-paper disk method (FPD) developed in Japan were performed to examine changes of gustatory function in active and inactive middle ear diseaes.
Seventy-five patients were examined before surgery from May to December 1997, with an average of 46.1 years old. They were classified as follows; A1 chronic otitis media (COM) without otorrhea (n=14); A2: COM with otorrhea (n=19), B1 cholesteatoma without otorrhea (n=4); B2: cholesteatoma with otorrhea (n=17); C1: surgically treated ears with CTN (n=6); C2 surgically treated ears without CTN (n=12); D: non-inflammatory disease (n=3). FPD tested four basic tastes, i.e., sweet, salty, sour and hitter, and thresholds of four kinds of test solutions expressed from I to V. Grades I and II were within normal range.
Results: 1)The average threshold of EGM was 3.4± 13.1 dB in A1, 11.3± 9.9 dB in A2, 2.5± 5.5 dB in B1, l0.5± l3.7 dB in B2, 4.0± 11.6 dB in C1, 27.6± 9.0 dB in C2, and 0 dB in D. 2) The rates of abnormal threshold of EGM (more than 8 dB of each group were 21.4%, 52.6%. 0%, 35.3%, 33.3% and 100%, respectively. 3) Thresholds of four kinds of tastes in FPD were almost the same (grade II-III) except groups C1 and C2 4) Subjective sense of taste disturbance was not evident in each group. The results suggested that patients with active middle ear inflammation showed elevation of threshold of EGM even if they did not feel taste disturbance