Model experiments of otoconia stability after canalith repositioning procedure of BPPV.
CONCLUSIONS
Postural restrictions are probably not necessary after the canalith repositioning procedure (CRP).


OBJECTIVE
Epley reported the effect of CRP for benign paroxysmal positional vertigo (BPPV). After CRP, patients are often requested to restrict postural change. However, some studies suggested that CRP may work without postural restrictions. The present study aimed to determine the necessity of post-maneuver postural restriction using the frog labyrinth model.


METHODS
The otoconial mass from the sacculus was placed on the utricular macular otoconia, mimicking a condition after CRP. The stability of the otoconial mass was observed by tilting the preparation, immediately, 3 min, and 5 min after it was placed on the macular otoconia. The utricular macula was maintained in the vertical plane for 10 s, during which period the behavior of the otoconial mass was observed. In experiment 1 the utricular macula was intact, in experiment 2 otoconia were partially removed, and in experiment 3 they were totally removed from the macula.


RESULTS
In experiments 1 and 2, in all preparations the otoconial mass became stabilized after 3 min. Even in experiment 3, in most preparations the otoconial mass became stabilized after 5 min.
Otsuka
Koji
K
Department of Otolaryngology, Tokyo Medical University, Japan. otsukaent@aol.com <otsukaent@aol.com>
Suzuki
Mamoru
M
Shimizu
Shigetaka
S
Konomi
Ujimoto
U
Inagaki
Taro
T
Iimura
Yoichi
Y
Hayashi
Mami
M
Ogawa
Yasuo
Y
D008267:Acoustic Maculae / Q000503:physiopathology*; D000818:Animals; D065635:Benign Paroxysmal Positional Vertigo; D023421:Models, Animal; D010037:Otolithic Membrane / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D011892:Rana catesbeiana; D014717:Vertigo / Q000503:physiopathology