[Neurootologic study of acoustic neuroma].

OBJECTIVE

To summarize the outcome of neurootologic examination of acoustic neuroma and study of diagnostic significance of neurootologic examination on acoustic neuroma.

METHOD: 13 patients were examined with pure tune test, acoustic immittance, electronystagmography, acoustic brainstem evoked response, electrocochleogram, otoacoustic emissions and facial electroneurography.

RESULT: All patients had subjective hearing loss. One patient had normal pure tone audiogram, other 4 patients had normal pure tone test at the frequency < 2000 Hz. The outcome of acoustic immittance is various. 5 patients were normal in caloric test, but all were abnormal in visual-vestibular optokinetic response. ABR are positive in 90.9% of cases, but 2 patients had no response. 7 patients were abnormal in facial electroneurography, 3 (of 3) eletrocochleogram and 2 (of 2) otoacoustic emissions revealed retrocochlear pathology.

CONCLUSION

Neurootologic examination played important role in filtering diagnosis of acoustic neuroma, results should be considered synthetically, acoustic neuroma should not be ruled out if any one test was negative.