Clinical significance of video head impulse test in benign paroxysmal positional vertigo: a meta-analysis

Purpose To document the effect of cupula deflection in Benign Paroxysmal Positional Vertigo (BPPV) through the measured Vestibulo-Ocular Reflex (VOR) gain in individual semi-circular canals. Methods A literature search using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed on December 30, 2020. The following terms were entered in the title, abstract, and keywords in the electronic databases of PubMed, Scopus, Web of Science, and Cochrane Library search engines in different combinations: "Benign Paroxysmal Positional Vertigo" or "Benign Positional Vertigo" or "BPPV," and "Video Head Impulse" or "vHIT". All types of studies were included in the initial search. An additional inclusion criterion was the presence of numerical values of VOR gains of the tested canals in the reports. Results A total of 122-screened articles were obtained from the electronic database search. Finally, the authors settled on five original articles for meta-analysis with a total of 168 patients (123 with posterior canal BPPV, 28 with lateral canal BPPV, and 17 with anterior canal BPPV) and 85 controls. The main outcomes of these studies comprised the VOR gains of the lateral, posterior, and anterior SCCs on the affected side relative to that in the contralesional side, and/or healthy controls. Conclusion This meta-analysis shows that vHIT can be valuable as a supporting test in the diagnosis of BPPV, especially for posterior canal BPPV.