ASL 3 Genovese, S.S. Vestibology and Vestibular Rehabilitation, Genoa, Italy.
San Pio Hospital, Department of Audiology and Phoniatrics, Benevento, Italy.
Acta Otorhinolaryngol Ital. 2023 Feb;43(1):49-55. doi: 10.14639/0392-100X-N2016.
To study the frequency of canal switch in posterior canal benign paroxysmal positional vertigo (BPPV) treated by canalith repositioning manoeuver (CRP), quick liberatory rotation manoeuver (QLR) or Semont manoeuver (SM).
Retrospective study on 1158 patients, 637 women and 521 men suffering from geotropic posterior canal BPPV treated by CRP, QLR, or SM, retested after 15 minutes and about seven days.
1146 patients recovered from the acute phase; treatments failed in 12 patients treated with CRP. We observed 12 canal switches from posterior to lateral canal and 2 from posterior to anterior canal during or after CRP in 13/879 cases (1.5%) and after QLR in 1/158 (0.6%) with no significant difference between CRP vs SM and QLR. We did not consider slight positional downbeat nystagmus after the therapeutic manoeuvers as a sign of canal switch into the anterior canal, but as a sign of persistent small debris in the non-ampullar arm of the posterior canal.
Canal switch is rare for any manoeuver and it does not belong to the criteria to choose one manoeuver over another. Notably, due to the canal switching criteria, SM and QLR cannot be preferred over those with a more prolonged extension of the neck.
研究后半规管良性阵发性位置性眩晕（BPPV）经管结石复位（CRP）、快速解脱旋转（QLR）或 Semont 手法（SM）治疗后的管转换频率。
回顾性研究了 1158 例女性 637 例、男性 521 例，患有向地性后半规管 BPPV，采用 CRP、QLR 或 SM 治疗，治疗后 15 分钟和大约 7 天进行复查。
1146 例患者在急性期恢复；12 例患者 CRP 治疗失败。我们观察到 13/879 例（1.5%）CRP 治疗期间或之后出现 12 例从后管向侧管转换，1/158 例（0.6%）QLR 治疗后出现 2 例从后管向前管转换，CRP 与 SM 和 QLR 之间无显著差异。我们没有将治疗手法后出现的轻微位置性下跳性眼球震颤视为前管转换的迹象，而是视为后半规管非壶腹臂内持续存在小碎片的迹象。
任何手法的管转换都很少见，它不属于选择一种手法而不是另一种手法的标准。值得注意的是，由于管转换标准，SM 和 QLR 不能优于那些颈部伸展时间更长的手法。
