Video head impulse test and caloric test in definite Meniere's disease

Purpose The objective of the study was to compare the results of caloric reflex tests and video head impulse tests (vHITs) of lateral semicircular canals (SCCs). Methods Patients aged over 18 years diagnosed with definite Meniere's disease (MD) according to the AAO-HNS 1995 criteria were recruited. Audiological tests, caloric tests and vHITs were conducted on all participants. A caloric weakness (canal paresis) of > 25% was considered significant. A VOR gain of < 0.8 in lateral or 0.7 in vertical SCCs was defined as significant. Patients were classified into active (having symptoms during the preceding 3 months) and inactive groups (free of symptoms for over 3 months). Results 51 patients (13 males and 38 females) participated. Caloric weakness was found in 39 patients (76.5%), while abnormal VOR gain was found in 24 (47.1%). The active group had 40 patients, and the inactive group had 11. There was statistical significance (p, 0.002) for disease duration but not for the caloric weakness and vHIT results of the two groups. Moreover, caloric weakness with an abnormal vHIT was not statistically significant, and there was no correlation between the two tests (r, 0.207) in lateral SCCs. The most common abnormal VOR gain in patients with caloric weakness was found in anterior SCCs. Conclusions The caloric test can detect abnormalities of the vestibular function better than vHIT in all stages of MD. However, the vHIT showed more specificity for the detection of abnormal SCC function. The vHIT test can be used as a screening tool and the caloric test should be considered if a vHIT result is normal.