Affiliations: [a] Department of Physical Therapy and Rehabilitation Science, University of Maryland, Baltimore, MD, USA | [b] Department of Otolaryngology Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, MD, USA | [c] Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, MD, USA
Correspondence:
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Corresponding author: Michael C. Schubert, PT, PhD, Department of Otolaryngology – Head and Neck Surgery, Johns Hopkins University School of Medicine, 601 N. Caroline St, 6th Fl, Baltimore, MD 21287, USA. Tel.: +1 410 955 9567; Fax: +1 410 955 6526; E-mail: [email protected]
Abstract: While active dynamic visual acuity (DVA) has been shown to improve with gaze stabilization exercises, we sought to determine whether DVA during {passive} head impulses (pDVA) would also improve following a rehabilitation course of vestibular physical therapy (VPT) in patients with unilateral and bilateral vestibular hypofunction. VPT consisted of gaze and gait stabilization exercises done as a home exercise program. Scleral search coil was used to characterize the angular vestibulo-ocular reflex (aVOR) during pDVA before and after VPT. Mean duration of VPT was 66 ± 24 days, over a total of 5 ± 1.4 outpatient visits. Two of three subjects showed improvements in pDVA with a mean reduction of 43% (LogMAR 0.58 to 0.398 and 0.92 to 0.40). Our data suggest improvements in pDVA may be due in part to improvements in aVOR velocity and acceleration gains or reduced latency of the aVOR. Each subject demonstrated a reduction in the ratio of compensatory saccades to head impulses after VPT. Preliminary data suggest that active gaze stability exercises may contribute to improvements in pDVA in some individuals.
