良性発作性頭位めまい症の患側はどちらか

─良性発作性頭位めまい症の特徴と 耳石置換法の対象とする患側の決定法─

抄録

Benign paroxysmal positional vertigo (BPPV) is the most common type of peripheral vertigo. BPPV occurs when calcium carbonate crystals (otoconia) in the utricle dislodge and migrate into the semicircular canals. There are two pathogeneses of BPPV: canalolithiasis and cupulolithiasis. Canalolithiasis involves to the presence of free cumulates of otoconia in the semicircular canals. When they become displaced in response to head movements, an endolymphatic flow is generated that abnormally stimulates the cupula, leading to vertigo. Cupulolithiasis involves a deposit of otolith nests that adhere to the cupula of the semicircular canal; thus, changing its specific gravity. Thus, the cupula is sensitized to linear accelerations, such as gravitational acceleration. The canalith repositioning procedure (CRP) is used to treat BPPV by moving the otoconia from the semicircular canal to the utricle. Although BPPV can resolve spontaneously, BPPV treated with CRP is resolved more quickly than untreated BPPV. In order to treat BPPV appropriately with the CRP, we must ensure its appropriate diagnosis.