Summary:
Benign paroxysmal positional vertigo (BPPV) is peripheral vertigo caused by a change in position. The pathophysiology
is tied to crystals of calcium carbonate, ectopically dislocated in the endolymph of semicircular
canals. Diagnosis is based on typical clinical history and findings on Dix-Hallpike positional test. Neither
oculography nor electronystagmography (ENG) examinations are routinely performed. We focused on
assessing the participation of functional disturbances of the inner ear in this diagnosis. Out of 36 patients
with positional vertigo, 33 had BPPV of the posterior canal. Out of these, 19 had a secondary form and 14
had idiopathic BPPV. Hearing was impaired in 20 patients (66%) – all patients with otosclerosis, Menière-
’s disease – but also 5 out of 10 patients with idiopathic BPPV. ENG findings corresponding to hypofunction
of the lateral canal ipsilateral to the BPPV were found in 5 patients, including 1 with idiopathic BPPV.
ENG typical of central vestibulocerebellar lesion was found in 3 patients, all with recurrent positional vertigo
of unknown etiology and with BPPV characteristics. Impaired inner ear function is frequently found
not only in secondary BPPV (17 out of 19 patients, 89 %) but also in the idiopathic form (6/14 patients – 43
%). In order to describe idiopathic BPPV with inner ear impairment of unknown etiology and undetectable
during routine examination, we propose the term „cryptogenic BPPV“.
Key words:
vertigo, positional vertigo, benign paroxysmal positional vertigo, hearing impairments, eye
movements, electronystagmography, audiometry
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