![]() In view of the high prevalence of BPPV in middle-aged women, hormonal factors may play a role in the development of BPPV. The cause of BPPV is mostly unknown (idiopathic). 9 This concept formed the theoretical basis of the canalith repositioning maneuvers (CRMs) to treat BPPV. 8 The concept of canalolithiasis was supported by the intraoperative observation of abundant free-floating debris in the endolymph of the posterior semicircular canal. In 1979, Hall proposed the concept of "canalolithiasis", which states that otolithic debris from the utricular macule migrates into the semicircular canal via the nonampullary portion, causing vertigo and nystagmus by moving freely inside the semicircular canal and inducing endolymph flow during positional changes. 7 However, the concept of cupulolithiasis has several limitations and is thus unable to explain all of the characteristics of nystagmus and vertigo in BPPV. 7 According to the theory, the cupula, which became heavy due to attached otolithic debris, could be deflected by position changes, thus evoking nystagmus. ![]() In 1969 he proposed the theory of "cupulolithiasis" on the basis of pathological studies that demonstrated otolithic debris attached to the cupula. Schucknecht was the first to provide a pathophysiological concept of BPPV. ![]() Keywords: vertigo, nystagmus, benign paroxysmal positional vertigo, canalith-repositioning maneuver However, canalithrepositioning maneuvers usually provide an immediate resolution of symptoms by clearing the canaliths from the semicircular canal into the vestibule. Spontaneous recovery may be expected even with conservative treatments. ![]() The duration, frequency, and symptom intensity of BPPV vary depending on the involved canals and the location of otolithic debris. Positioning the head in the opposite direction usually reverses the direction of the nystagmus. Paroxysm of vertigo and nystagmus develops after a brief latency during the Dix-Hallpike maneuver in posterior-canal BPPV, and during the supine roll test in horizontal-canal BPPV. Typical symptoms and signs of BPPV are evoked when the head is positioned so that the plane of the affected semicircular canal is spatially vertical and thus aligned with gravity. BPPV is the most common etiology of recurrent vertigo and is caused by abnormal stimulation of the cupula by free-floating otoliths (canalolithiasis) or otoliths that have adhered to the cupula (cupulolithiasis) within any of the three semicircular canals. Benign paroxysmal positional vertigo (BPPV) is characterized by brief recurrent episodes of vertigo triggered by changes in head position. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |