video Head Impulse Test (vHIT) を用いた中耳病変を伴う病態における半規管機能評価

抄録

　The video Head Impulse Test (vHIT) is a novel test that allows evaluation of the functions of the semicircular canals, including of the vertical semicircular canals. vHIT has many advantages over caloric testing; for example, it is both less invasive and less time-consuming than caloric testing. In addition, vHIT allows evaluation of the functions of the semicircular canals in patients with lesions in the external or middle ear, as the semicircular canal functions in this test are evaluated by recording the head and eye movements during the vestibulo-ocular reflex (VOR). It is important to evaluate vestibular functions for making appropriate treatment decisions. However, caloric testing might be inappropriate for patients with external or middle ear pathologies, as in these patients, stimulation with cold water might not be transmitted appropriately to the horizontal semicircular canal; as examples, patients with cholesteatoma, otitis media with ANCA-associated vasculitis, acute otitis media, otitis media with effusion and facial nerve schwannoma have been cited. In this review, evaluation of the functions of the semicircular canals in patients with middle ear pathologies by vHIT are described.