Systematic Evaluation of Diagnostic Tests Including Vestibular Evoked Myogenic Potentials and Multi-Frequency Tympanometry in the Differential Diagnosis of Episodic Vertigo

Objective: To evaluate the additional role of multi-frequency tympanometry (MFT) and vestibular evoked myogenic potentials (VEMP) in the differential diagnosis of episodic vertigo. Study Design: Controlled cross-sectional. Setting: Tertiary referral center. Patients: 60 samples (15 healthy controls(HC), 15 Meniere's disease(MD), 15 recurrent vestibulopathy(RV), 15 migrainous vertigo(MV)) were included. Interventions: Pure tone audiometry, VEMP and MFT were performed to all patients and healthy controls, caloric test was performed only to the patients. Main Outcome Measure: "Audio-vestibular diagnosis score" was described and calculated which was based on the evaluation of the results of four diagnostic tests. Results: Ear resonance frequency (RF) was 921.6 Hz and 1092.3 Hz in healthy subjects and Meniere patients respectively (p<0.01). VEMP thresholds were 84 and 97.3 dB on 250 Hz, 89 and 104 dB on 500 Hz, 97.6 and 110.7 Hz on 1000 Hz in HC and MD respectively (p<0.01). "Audio-vestibular diagnosis score" was effective in differentiating MD from other etiologies (p<0.01). Conclusions: RF was significantly higher in MD and this might indicate pressure of the hydropic saccule on stapes footplate. VEMP thresholds were significantly higher in MD. "Audio-vestibular diagnosis score" was helpful in the differential diagnosis of episodic vertigo with the additional role of MFT and VEMP especially in patients with RV or patients with ovelapping diseases such as MD+Migraine or MV+hearing loss. Relatively normal inner ear function in MV patients may enlighten the controversial pathophysiology of this disease in the favor of central hypotheses.