Kitahara T, et al. - Experts evaluated the relationship of neuro-otological examination, blood test, and scoring questionnaire data with treatment-resistant intractability in idiopathic benign paroxysmal positional vertigo (BPPV) patients. BPPV could become intractable by the presence of horizontal type cupula (hBPPVcu), canal paresis, endolymphatic hydrops, and elevated bone alkaline phosphatase (BAP), nonetheless, patients with idiopathic BPPV are usually treatable and curable within 1 month. Therefore these patients require additional treatments.

Methods

• Authors experienced 1520 successive vertigo/dizziness patients at the Vertigo/Dizziness Center in Nara Medical University during May 2014 to April 2018.
• According to the diagnostic guideline of the International Classification of Vestibular Disorder in 2015, 611 patients were diagnosed as BPPV (611/1520; 40.2%).
• There were 201 intractable patients (201/611; 32.9%) among BPPV patients, 66 of whom were idiopathic and enrolled to be hospitalized and receive neuro-otological examinations, including the caloric test (C-test), vestibular evoked cervical myogenic potentials (cVEMP), subjective visual vertical (SVV), glycerol test (G-test), electrocochleogram (ECoG), inner ear magnetic resonance imaging (ieMRI), blood tests including anti-diuretic hormone (ADH) and bone alkaline phosphatase (BAP), and self-rating questionnaires of depression score (SDS).
• They diagnosed 66 patients as horizontal type cupula (hBPPVcu; n=30), horizontal type canal (hBPPVca; n=10), posterior type (n=20), and probable and/or atypical BPPV (n=6).
• They presented the data as ratios (+) of the number of idiopathic BPPV patients with examination and questionnaire data outside of the normal range.

Results

• Findings suggested that the ratio (+) data were as follows: C-test=21.2% (14/66), cVEMP=24.2% (16/66), SVV=48.5% (32/66), G-test=18.2% (12/66), ECoG=18.2% (12/66), ieMRI=12.1% (8/66), ADH=9.1% (6/66), BAP=13.6% (9/66), and SDS=37.9% (25/66).
• Significantly longer periods of persistent vertigo/dizziness were seen in BPPV patients with hBPPVcu, C-test (+), endolymphatic hydrops (+), and BAP (+) compared with those with negative findings; as seen on multivariate regression analysis.