Posterior SCC BPPV is the most common type of BPPV and can be tested by the Dix-Hallpike test. Nystagmus features Posterior semicircular BPPV Nystagmus must be observed during a provoking maneuver as described below to confirm BPPV. These vertigo spells may be associated with nausea and vomiting but patients do not complain of hearing loss or other neurologic symptoms. Patients with BPPV present with recurrent episodes of vertigo that last less than 1 minute and are provoked by changes in head movements relative to gravity. Resulting alterations in cupular deflection lead to pathological perceptions of motion. Cupulolithiasis – proposes that the otoconial debris is attached to the cupula of the affected SCC instead of free-floating in the endolymph.Gravity pulls the otoconia through the endolymph canal, creating a plunger-like effect which causes ipsidirectional cupular displacement. Canalithiasis – proposes that free-floating particles, otoconia, have moved from the utricle and collect near the cupula of the affected SCC.They differ with respect to how the debris influences cupular dynamics: Two theories exist for the mechanism of action of BPPV. Observing nystagmus during a provoking maneuver helps ascertain the diagnosis of BPPV in patients with a typical history and can identify the laterality and specific canal affected. Whilst vertigo typically does not present to ophthalmologists, the symptoms of the sensation of motion (i.e., oscillopia), blurred vision and the presence of nystagmus make it important for ophthalmologists to have some understanding of vertigo including BPPV. Patients typically have no hearing loss or other neurologic complaints. Recurrent episodes of vertigo may be accompanied by nausea and vomiting and can recur periodically for weeks to months. The posterior SCC is most commonly affected. Debris in the SCC causes inappropriate endolymph movement with changes in position, and therefore causes the sensation of vertigo with positional movement. BPPV is commonly attributed to calcium debris within the semicircular canals (SCC), which normally detect angular head accelerations. 3.1.2 Horizontal/Lateral semicircular canal BPPVīenign paroxysmal positional vertigo (BPPV) is a common form of acute vertigo characterized by brief (
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