Decision Analysis in Diagnosis of Small Acoustic Tumors

Abstract

BACKGROUND AND OBJECTIVES: With great development that took place in the last 10 years in the imaging techniques such as MRI with gadolinium, small acoustic tumors can be detected before significant symptoms have developed. However, suspicion of acoustic neuroma is not easy at its earlier stage due to the lack of its characteristic symptoms. The detection rate of acoustic neuroma using traditional audiologic methods such as ABR and pure tone audiogram with speech discrimination score is relatively low contrary to expectation. Therefore, there is a need to develop other methods of diagnosis at an earlier stage. The aim of this study was to review symptomatology, diagnostic approach and the management of acoustic neuroma and to make a decision analysis tree of the diagnostic work-up. MATERIALS AND METHODS: From June 1994 through May 1998, eight patients with a small acoustic neuroma were treated at Ajou University Hospital. We analysed these 8 patients by age, sex, chief complaint, size of tumor, preoperative and postoperative audiologic studies, caloric test, treatment modalities and preoperative and postoperative imaging study. RESULTS: Acoustic neuroma had variable symptoms, with the most common initial symptom of our cases being sudden hearing loss. The sensitivity of ABR was relatively lower than we thought. Two out of three in the observation group showed an abrupt deterioration of hearing. CONCLUSION: When acoustic neuroma is suspected in patients with unilateral hearing loss, tinnitus and dizziness are very important symptoms to consider. We developed a decision analysis tree for diagnosis of small acoustic neuroma, which should be treated with earlier intervention of MRI.