Video head impulse testing: Pitfalls in neurological patients.

The video head impulse test (vHIT) assesses the vestibulo-ocular reflex (VOR) during a rapid high-velocity low amplitude (10°-20°) head rotation. Patients with peripheral vestibulopathy have a reduced VOR gain with corrective catch-up saccades during the head turn. There are several pitfalls, mainly technical, which may interfere with interpretation of vHIT data. In addition, intrusive eye movement disorders such as spontaneous nystagmus that affect normal eye position and tracking can affect the vHIT results. To date there has been little study of neurological saccadic eye movements that may interfere with the interpretation of vHIT data. Here, in ten patients with a range of central neurological disorders, we describe oculomotor abnormalities on vHIT in the presence of normal range VOR gain values, recorded at a tertiary vestibular neurology service.

Are Cervical Collars a Necessary Postprocedure Restriction in Patients With Benign Paroxysmal Positional Vertigo Treated With Particle Repositioning Maneuvers?

INTRODUCTION: Benign paroxysmal positional vertigo (BPPV) is managed with particle repositioning maneuvers (PRM), following which patients are advised of activity restrictions to prevent recurrence. This can include wearing a cervical collar. OBJECTIVE: Does the use of BPPV postprocedure restriction with a cervical collar impact on the number of PRMs required to resolve a patient's symptoms? METHOD: Combination of retrospective and prospective review of 624 patients treated in a tertiary UK hospital. All were diagnosed with posterior canal BPPV and received a modified Epley maneuver (PRM). The "with cervical collar" (WC) retrospective group 2002 to 2009 (n = 263) were advised to wear a cervical collar for 48 hours postprocedure, and the "no cervical collar" (NC) prospective group 2010 to 2014 (n = 361) were not. The main outcome measure was the resolution of patient symptoms following a PRM for BPPV. Quantitative and statistical analysis using χ test was undertaken. RESULTS: In the WC group, 84% (n = 221) had resolution of symptoms after the first PRM, versus 82.8% (n = 299) in the NC group. After the second PRM 11% (n = 29) resolved, versus 13.6% (n = 49) in the NC group. After the third PRM 4.9% (n = 13) resolved, versus 3.6% (n = 13) in the NC group. Both clinically and statistically there was no significant difference in outcome between groups. CONCLUSIONS: Our review of 624 patients is the largest study in this subject and the results demonstrate that wearing a cervical collar following PRM for BPPV concedes no significant benefit. Excluding this from postprocedure guidance allows patients to manage without the inconvenience of wearing a cervical collar, and allows departments to update clinical guidance.