Efficacy of intergrating vestibular rehabilitation and cognitive behaviour therapy in persons with persistent dizziness in primary care- a study protocol for a randomised controlled trial.

BACKGROUND: Dizziness is a common complaint, and the symptom often persists, together with additional complaints. A treatment combining Vestibular Rehabilitation (VR) and Cognitive Behaviour Therapy (CBT) is suggested. However, further research is necessary to evaluate the efficacy of such an intervention. The objective of this paper is to present the design of a randomised controlled trial aiming at evaluating the efficacy of an integrated treatment of VR and CBT on dizziness, physical function, psychological complaints and quality of life in persons with persistent dizziness. METHODS/DESIGN: The randomised controlled trial is an assessor-blinded, block-randomised, parallel-group design, with a 6- and 12-month follow-up. The study includes 125 participants from Bergen (Norway) and surrounding areas. Included participants present with persistent dizziness lasting for at least 3 months, triggered or exacerbated by movement. All participants receive a one-session treatment (Brief Intervention Vestibular Rehabilitation; BI-VR) with VR before being randomised into a control group or an intervention group. The intervention group will further be offered an eight-session treatment integrating VR and CBT. The primary outcomes in the study are the Dizziness Handicap Inventory and preferred gait velocity. DISCUSSION: Previous studies combining these treatments have been of varying methodological quality, with small samples, and long-term effects have not been maintained. In addition, only the CBT has been administered in supervised sessions, with VR offered as home exercises. The current study focusses on the integrated treatment, a sufficiently powered sample size, and a standardised treatment programme evaluated by validated outcomes using a standardised assessment protocol. TRIAL REGISTRATION: www.clinicaltrials.gov, ID: NCT02655575 . Registered on 14 January 2016.

Feasibility of integrating vestibular rehabilitation and cognitive behaviour therapy for people with persistent dizziness.

PURPOSE: To evaluate the feasibility of integrating vestibular rehabilitation and cognitive behaviour therapy (VR-CBT) for people with persistent dizziness in primary care. DESIGN: Prospective single-group pre- and post-test study. PARTICIPANTS: Adults (aged 18-70) with acute onset of dizziness and symptoms lasting a minimum 3 months, recruited from Bergen municipality. METHODS: Participants attended eight weekly group sessions of VR-CBT intervention. Feasibility outcomes consisted of recruitment and testing procedures, intervention adherence, and participant feedback, besides change in primary outcomes. The primary outcomes were Dizziness Handicap Inventory (DHI) and preferred gait velocity. RESULTS: Seven participants were recruited for the study. All participants completed the pre-treatment tests, five participants completed the intervention and answered post-treatment questionnaires, and three completed post-treatment testing. Of the five participants, three attended at least 75% of the VR-CBT sessions, and two 50% of the sessions. Participants reported that the VR-CBT was relevant and led to improvement in function. DHI scores improved beyond minimal important change in two out of five participants, and preferred gait velocity increased beyond minimal important change in two out of three participants. CONCLUSION: The current tests and VR-CBT treatment protocols were feasible. Some changes are suggested to optimise the protocols, before conducting a randomised controlled trial. TRIAL REGISTRATION: NCT02655575. Registered 14 January 2016-retrospectively registered.

Short-term information pattern in optokinetic nystagmus amplitude time series.

In this paper we analyzed optokinetic nystagmus (OKN) signals for underlying information patterns. Fourteen OKN signals were recorded in five healthy subjects. First, we tested the correlation between nystagmus slow and fast phases. Previously, it has been suggested that the correlation is higher between the amplitude of the slow phase and the following fast phase, compared to the correlation between the fast phase and the following slow phase. However, we found no such difference. This is in agreement with the view that the saccade performed by the eye is not determined by the previous slow phase, but is free to move voluntarily in order to focus on an object of interest. Second, we analyzed the information entropy contained in the sequence of optokinetic nystagmus amplitudes, and found a short-term information pattern. Further analysis of these patterns could eventually lead to more knowledge about the vestibular and oculomotor systems.

Postural control in a simulated saturation dive to 240 msw.

INTRODUCTION: There is evidence that increased ambient pressure causes an increase in postural sway. This article documents postural sway at pressures not previously studied and discusses possible mechanisms. METHODS: Eight subjects participated in a dry chamber dive to 240 msw (2.5 MPa) saturation pressure. Two subjects were excluded due to unilateral caloric weakness before the dive. Postural sway was measured on a force platform. The path length described by the center of pressure while standing quietly for 60 seconds was used as test variable. Tests were repeated 38 times in four conditions: with eyes open or closed, while standing on bare platform or on a foam rubber mat. RESULTS: Upon reaching 240 msw, one subject reported vertigo, disequilibrium and nausea, and in all subjects, mean postural sway increased 26% on bare platform with eyes open (p < 0.05) compared to predive values. There was no significant improvement in postural sway during the bottom phase, but a trend was seen toward improvement when the subjects were standing with eyes closed on foam rubber (p = 0.1). Postural sway returned to predive values during the decompression phase. DISCUSSION: Postural imbalance during deep diving has been explained previously as HPNS possibly including a specific effect on the vestibulo-ocular reflex. Although vertigo and imbalance are known to be related to compression rate, this study shows that there remains a measurable increase in postural sway throughout the bottom phase at 240 msw, which seems to be related to absolute pressure.