Chronic symptoms after vestibular neuritis and the high velocity vestibulo-ocular reflex

Hypothesis: As the anterior and posterior semicircular canals are vital to the regulation of gaze
stability, particularly during locomotion or vehicular travel, we tested whether the high velocity
vestibulo‐ocular reflex (VOR) of the three ipsilesional semicircular canals elicited by the
modified Head Impulse Test would correlate with subjective dizziness or vertigo scores after
vestibular neuritis (VN).
Background: Recovery following acute VN varies with around half reporting persistent
symptoms long after the acute episode. However, an unanswered question is whether chronic
symptoms are associated with impairment of the high velocity VOR of the anterior or posterior
canals.
Methods: Twenty patients who had experienced an acute episode of VN at least three months
earlier were included in this study. Participants were assessed with the video head impulse test
(vHIT) of all six canals, bithermal caloric irrigation, the Dizziness Handicap Inventory (DHI) and
the Vertigo Symptoms Scale short‐form (VSS).
Results: Of these 20 patients, 12 felt that they had recovered from the initial episode whereas 8
did not and reported elevated DHI and VSS scores. However, we found no correlation between
DHI or VSS scores and the ipsilesional single or combined vHIT gain, vHIT gain asymmetry or
caloric paresis. The high velocity VOR was not different between patients who felt they had
recovered and patients who felt they had not.
Conclusions: Our findings suggest that chronic symptoms of dizziness following VN are not
associated with the high velocity VOR of the single or combined ipsilesional horizontal, anterior
or posterior semicircular canals.