AUTHOR=Li Ming , Leng Yangming , Liu Bo 

TITLE=Clinical Implication of Caloric and Video Head Impulse Tests for Patients With Enlarged Vestibular Aqueduct Presenting With Vertigo

JOURNAL=Frontiers in Neurology

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2021.717035

DOI=10.3389/fneur.2021.717035

ISSN=1664-2295

ABSTRACT=Background: By examining the clinical features and results of video head impulse test (vHIT) and caloric tests in patients with enlarged vestibular aqueduct (EVA) presenting with vertigo, we aimed to investigate the function of angular vestibulo-ocular reflex (VOR) and its clinical implications. 
Methods: Nine patients with EVA manifesting with vertigo were enrolled. The medical history, audiological examination, imaging, and the results of the caloric test and the vHIT were analyzed. 
Results: Of the 9 patients with EVA (8 bilateral and 1 unilateral case), 5 were pediatric cases. All 17 ears exhibited sensorineural hearing loss. EVA patients can present with recurrent (7 cases) or single (2 cases) vertigo attack, trauma-induced (2 cases) or spontaneous (7 cases) vertigo. Diminished caloric responses were observed in 77.8% (7/9) of the patients (4 cases unilaterally and 3 bilaterally), while unilateral abnormal vHIT results in 11.1% (1/9) patients. Abnormal caloric and normal horizontal vHIT responses were found in 66.7% (6/9) of EVA patients. 
Conclusions: Vestibular manifestations in EVA are diverse. EVA patients with vertigo can present with a reduced caloric response and normal horizontal vHIT, and this pattern of angular VOR impairment was also found in other hydropic ear diseases.