Caloric Analysis of Patients with Benign Paroxysmal Positional Vertigo.

OBJECTIVE: The aim of this study is to compare nystagmus characteristics after caloric irrigation in patients with lateral canal (LC) and posterior canal (PC) benign paroxysmal positional vertigo (BPPV) and to analyze the role of symptom duration. MATERIALS and METHODS: A prospective study was conducted in 65 patients with BPPV (20 LC and 45 PC) who were subjected to caloric testing. Average slow-phase velocity and nystagmus duration were analyzed. RESULTS: Caloric hypo-excitability was 20.4%. It was more evident in patients with apogeotropic-type LC-BPPV. The comparison of average slowphase velocity of the nystagmus and nystagmus duration between selected types of BPPV for pathologic, non-pathologic, and the control ears after warm and cold stimulation was not statistically significant (p>0.05). No correlation was found between caloric results and symptom duration (p>0.05). CONCLUSION: Some patients presented caloric hypo-excitability. Reliability of caloric testing to differentiate the ear with normal and abnormal vestibular function in different types of BPPV was low. No difference was found in the analysis of the impact of symptom duration. Caloric testing is not an ideal tool to study BPPV [ABSTRACT FROM AUTHOR]