発作性頭位眩暈症

良性、仮性良性ならびに悪性の鑑別診断の要点

抄録

It is generally accepted that positional vertigo might result both from lesions in the central nervous system and from lesions in the peripheral vestibular organ. In 1921, Bardny described a characteristic paroxysmal vertigo and nystagmus occurring in a certain critical position, and he suggested that the pathogenesis of this condition was related to otolith disease. In 1952, Dix and Hallpike described positional vertigo of the benign paroxysmal type (BPPN) due to a disorder of the otolith.
This nyatagmus is very characteristic and nowadays is widely accepted among clinicians as a nystagmus due to otolith lesions. Furthermore, this characteristic nystagmus has become one of the most reliable signs for diagnosing vertigo due to disorder of peripheral vestibular organs. Although there have been numbers published papers describing positional vertigo due to lesions within the central nervous system (Bruns, 1902 ; Alpers and Yaskin, 1944 ; Allen and Fernandez, 1960 ; Fernandez and Alzate, 1960 ; Sakata u. a., 1979 ; Sakata, Ohtsu and Takahashi, 1984), most of these cases are not of the benign paroxysmal type.
Recently, we have treated several patients with typical nystagmus of the benign paroxysmal ty-pe due to lesions in the cerebellar vermis. We discussed the differential diagnosis of BPPN, Pseudo-BPPN and MPPN.