Video head impulse test can detect brainstem dysfunction in multiple sclerosis

Abstract

BackgroundThe aim of this study was to investigate the potential role of video head impulse test (vHIT) in the detection of brainstem lesions in patients with multiple sclerosis (MS). MethodsSixty-eight participants were enrolled and divided into two groups: 39 healthy subjects (HC) (78 ears, 20 females, mean age 25,3±6,3) and 29 MS patients (58 ears, 14 females, mean age 33,7±7,7). Both groups underwent vHIT, and in MS group MRI was analyzed for the presence of brainstem lesions. vHIT pathology was defined as presence of overt saccades (<200ms) or lateral gain lower than 0.8 for lateral canal, and presence of overt saccades (<200ms) or posterior/anterior slope lower than 0.7. ResultsIn HC, decreased gain on horizontal canals was found in 8 out of 78 ears (11%), while 16 out of 58 ears (38%) had pathological results in the MS group. Mean gain of the lateral canals (60ms) was significantly reduced in MS group compared to HC (0.874±0143 vs. 0.954±0,170, p=0.004, respectively). Compared to HC overt saccades <200ms in the lateral canals (p=0.018) and in the posterior canals (p=0.011), overt saccades >200ms in lateral (p<0.001), anterior (p=0.019) and posterior canals (p=0.009), and covert saccades in the anterior (p=0.042) and posterior canals (p=0.046) were more frequent in the MS group. There was statistically significant association between the presence of BS MR lesions and bilateral pathology on vHIT for lateral semicircular canal (χ(1)=3.982, p=0.046). ConclusionThese results indicate that vHIT can detect brainstem dysfunction in patients with MS.