To the best of our knowledge, this is the first class I study on the efficacy of the GLM in the treatment of LC-BPPV in both geotropic and apogeotropic forms. GLM proved highly effective compared to the sham maneuver (P < 0.0001). The present class I study of the efficacy of the GLM changes the level of recommendation of the method for treating LC-BPPV from level U to level B for the geotropic variant and from level B to level A for the apogeotropic variant of LC-BPPV.

The need for Class I and II studies on the efficacy of Semont's liberatory maneuver (SLM) in the treatment of posterior canal benign paroxysmal positional vertigo (PC-BPPV) motivated the present double-blind randomized trial on the short-term efficacy of SLM. A total of 342 patients with unilateral PC-BPPV were recruited for a multicenter study. Patients were randomly assigned to treatment by SLM (n = 174) or sham treatment (n = 168). Subjects were followed up twice (1 and 24 h) with the Dix-Hallpike maneuver by blinded examiners. At the 1 and 24 h follow-up, 79.3 and 86.8%, respectively, of patients undergoing SLM had recovered from vertigo, compared to none of the patients undergoing the sham maneuver (p < 0.0001). Patients who manifested liberatory nystagmus at the end of SLM showed a significantly higher percentage of recovery (87.1 vs. 55.7%; p < 0.0001). To the best of our knowledge, this is the first Class I study on the efficacy of SLM. SLM proved highly effective with respect to the sham maneuver (p < 0.0001). Liberatory nystagmus was demonstrated to be a useful prognostic factor for the efficacy of treatment. The present Class I study of efficacy of SLM changes the level of recommendation of the maneuver for treating PC-BPPV from level C to level B.

No abstract

We describe a rare case of posterior semicircular canal (PSC) fibrosis following acute labyrinthine ischemia in the territory supplied by the common cochlear artery (CCA) and review the relevant literature. A 71-year-old man with multiple vascular risk factors presented 12 days after the onset of acute vertigo and profound left-sided hearing loss. Right-beating spontaneous nystagmus with downbeat components elicited by mastoid vibrations and headshaking was detected. The video head impulse test (vHIT) revealed an isolated hypofunction of the left PSC, whereas vestibular evoked myogenic potentials (VEMPs) showed ipsilateral saccular loss. The clinical presentation and instrumental picture were consistent with acute ischemia in the territory supplied by left CCA. Compared to previous imaging, a new MRI of the brain with 3D-FIESTA sequences highlighted a filling defect in the left PSC, consistent with fibrosis. Hearing function exhibited mild improvement after steroid therapy and hyperbaric oxygen sessions, whereas vHIT abnormalities persisted over time. To the best of our knowledge, this is the only case in the literature reporting a filling defect on MRI, consistent with semicircular canal fibrosis following acute labyrinthine ischemia. Moreover, PSC fibrosis was related with poor functional outcome. We therefore suggest using balanced steady-state gradient-echo sequences a few weeks following an acute lesion of inner ear sensors to detect signal loss within membranous labyrinth consistent with post-ischemic fibrosis. Besides addressing the underlying etiology, signal loss might also offer clues on the functional behavior of the involved sensor over time. In cases of acute loss of inner ear function, a careful bedside examination supplemented by instrumental assessments, including vHIT and VEMPs, of vestibular receptors and afferents may be completed by MRI with balanced steady-state gradient-echo sequences at a later time to confirm the diagnosis and address both etiology and functional outcome.