Diagnostic Role of Head-Bending and Lying-Down Tests in Lateral Canal Benign Paroxysmal Positional Vertigo

Objectives To compare the diagnostic value of the head-bending test (HBT), lying-down positioning test (LDPT) and patient's report to identify the affected canal in video-nystagmographically (VNG) confirmed patients with lateral canal benign paroxysmal positional vertigo (LC-BPPV). Study Design Case series with chart review. Setting Head-bending, lying-down positioning and the head-roll maneuver (HRM) under VNG guidance. The data were collected in a referral community hospital. Patients Seventy-eight patients (32 apogeotropic and 46 geotropic nystagmus) with LC-BPPV who had been recruited between 2009 and 2013 were enrolled in the study. Main Outcome Measures Patients were tested with the HRM and then were asked about subjectively worse side. Later, they were subjected to HBT when sitting and the LDPT. The results were compared and studied with the 1-way ANOVA and chi-square tests. Statistical significance was set at p < 0.05. Results Affected side was identified by HRM in 75% of patients with apogeotropic nystagmus and 95.6% of patients with geotropic nystagmus. Approximately 65.6% of patients with apogeotropic and 52% of patients with geotropic nystagmus had nystagmus during LDPT. However, its comparability with HRM was low. However, treatment plan based on LDPT results alone provided relief of symptoms in additional 12.5% of patients with apogeotropic and in 2.2% of patients with geotropic nystagmus. Approximately 63% of patients with apogeotropic and 56% of patients with geotropic nystagmus were able to tell the worse side. Nystagmus comparable with HRM during HBT was low and not diagnostic. Conclusion HRM has the greatest diagnostic value of positioning tests in LC-BPPV in this study. LDPT provides some contribution in the diagnosis of LC-BPPV but much less than HRM. Patients ' subjective feeling of vertigo was also a useful test. However, HBT was not as sensitive as other measures in uncertain cases.