Utility measures of health-related quality of life in patients treated for benign paroxysmal positional vertigo.

OBJECTIVES: Comparing the effects of different disorders and interventions on health-related quality of life (HRQoL) is important for healthcare policy and accountability. There are two basic approaches to measure HRQoL: questionnaires derived from psychometrics and preference-based measures or utilities derived from econometrics. While disease-specific HRQoL questionnaires, such as the Dizziness Handicap Inventory (DHI), are important because they focus on the impact of a specific problem and its treatments (i.e., vestibular disorders), economic comparisons of the impacts of diseases/disorders and their treatments are typically based on utility assessment. The utility measures for audiology application (UMAA) were developed to measure utilities for various audiologic conditions using a standard computer. The purpose of this study was to determine if the UMAA provides stable, valid, and sensitive utility measures of the effects of benign paroxysmal positional vertigo (BPPV) and its treatment on HRQoL. It was hypothesized that utilities, as measured by the UMAA, would indicate improvement in HRQoL post-treatment for BPPV comparable to a disease-specific health status measure (DHI). DESIGN: The UMAA incorporates three techniques to measure utility: rating scale, standard gamble, and time tradeoff. A utility is a cardinal measure of strength of preference and is measured on a continuum basis from 0.0 (incapacitating dizziness) to 1.0 (no dizziness). Fifty-two adults with BPPV of the posterior semicircular canal completed the UMAA and DHI before treatment and again post-treatment. A subgroup of 15 participants completed the UMAA on two occasions before treatment to assess test-retest stability and to establish critical difference values. RESULTS: Results from this investigation demonstrate that utilities as measured through the UMAA are stable, valid, and comparable to the DHI. Post-treatment utilities were also significantly higher than pretreatment utilities, indicating that the utilities, as measured through the UMAA, are sensitive to improvement in HRQoL after BPPV treatment. CONCLUSIONS: Utilities as measured through the UMAA seem sensitive to changes in HRQoL after treatment of BPPV. Since the UMAA can be used to measure patient preference (i.e., utility), it may be useful for comparison of specific audiologic conditions, such as BPPV, to nonaudiologic conditions, such as cardiovascular disease and kidney disease.

Vestibular Toxicity: Causes, Evaluation Protocols, Intervention, and Management.

The loss of vestibular function, typically bilateral, due to chemical solvents and pharmacological agents is not rare and has been investigated and reported for many years. The successful treatment of bacterial infections and sepsis with IV antibiotics and cancer-fighting drugs like cisplatin makes the decision to use these life-saving drugs less of a debate, despite their potential deleterious effect on balance and equilibrium. The purpose of this article is to provide the reader with an overview of the more common substances found in industry and medicine which may decrease or permanently destroy peripheral and/or central vestibular function. A review of bedside and clinical evaluation protocols will be discussed as well as best practice intervention with balance retraining therapy. Finally, the role of the audiologist and opportunities for participation in an interdisciplinary approach to evaluation and management will be presented.

Comparison of horizontal and vertical dynamic visual acuity in patients with vestibular dysfunction and nonvestibular dizziness.

Blurred vision with head movement is a common symptom reported by patients with vestibular dysfunction affecting the vestibulo-ocular reflex (VOR). Impaired VOR can be measured by comparing visual acuity in which there is no head movement to visual acuity obtained with head movement. A previous study demonstrated that dynamic visual acuity (DVA) testing using vertical head movement revealed deficits in impaired VOR. There is evidence that horizontal head movement is more sensitive to impaired VOR. The objective of this investigation was to compare horizontal and vertical DVA in participants with normal vestibular function (NVF), impaired vestibular function (IVF), and participants with nonvestibular dizziness (NVD). Participants performed the visual acuity task in a baseline condition with no movement and also in two dynamic conditions, horizontal head movement and vertical head movement. Horizontal DVA was twice as sensitive to impaired VOR than vertical DVA. Results suggest that horizontal volitional head movement should be incorporated into tasks measuring functional deficits of impaired VOR.

Computerized dynamic visual acuity with volitional head movement in patients with vestibular dysfunction.

OBJECTIVES: Patients with uncompensated vestibular dysfunction frequently report blurred vision during head movement, a symptom termed oscillopsia. One way to measure the functional deficit associated with an impaired vestibulo-ocular reflex is by comparing visual acuity from a baseline condition in which there is no head movement to visual acuity obtained during a dynamic condition with head movement. A previously described test incorporated a treadmill upon which patients walked during assessment of visual acuity. The objective of the current investigation was to evaluate an alternative method of assessing dynamic visual acuity that uses volitional head movement instead of walking on a treadmill. METHODS: Fifteen participants with normal vestibular function and 16 participants with impaired vestibular function were enrolled. All participants performed the visual acuity task under baseline conditions with no movement and also under dynamic conditions that included 1) walking on a treadmill and 2) volitionally moving their head in the vertical plane. RESULTS: No difference in performance was observed between the treadmill task and the volitional head movement task. Participants with impaired vestibular function performed more poorly under the dynamic conditions than did participants with normal vestibular function. CONCLUSIONS: The results suggest that the volitional head movement paradigm may be useful in identification of patients with functional deficits of the vestibulo-ocular reflex.

Efficacy of a new treatment maneuver for posterior canal benign paroxysmal positional vertigo.

Existing treatment maneuvers for posterior canal benign paroxysmal positional vertigo (PC-BPPV) include the Semont liberatory maneuver (SLM) and canalith repositioning maneuver (CRM). Independent investigations reveal that these maneuvers provide an excellent outcome for most patients. However, certain aspects of these maneuvers, such as hyperextension of the neck for CRM and brisk lateral motion for the SLM, are contraindicated for patients with vertebrobasilar insufficiency, cervical spondylosis, back problems, and so forth. A hybrid approach, the Gans repositioning maneuver (GRM) was developed for use with these patients. The purpose of this project was to assess efficacy of the GRM for treatment of PC-BPPV. Two-hundred seven participants were enrolled in this prospective study. All participants were treated with the GRM. Six different clinicians performed the treatments. Participants returned for follow-up at one-week intervals until it was determined that the PC-BPPV was clear. On average, 1.25 GRM treatments were required to resolve the PC-BPPV. The majority of the participants (80.2%) were cleared with one GRM treatment, and 95.6% were clear after two treatments. Recurrence rate was 5%. There was no difference in outcome based on clinician. The GRM is an efficacious treatment maneuver for PC-BPPV and may be preferential for use in patients with neck, back, hip, and/or mobility issues that contraindicate the use of SLM or CRM.

Treatment of benign paroxysmal positional vertigo: necessity of postmaneuver patient restrictions.

Benign paroxysmal positional vertigo (BPPV) is the most common cause of vertigo, resulting from migration of otoconia into the semicircular canals. Several treatment methods involving positioning maneuvers that return the otoconia to the utricle have been described. Following treatment, most patients are provided with a variety of activity restrictions. Previous studies suggest that, overall, BPPV treatment may be successful without these restrictions. The purpose of this study was to determine the necessity of postmaneuver restrictions using an experimental and control group with participants matched for age, gender, involved ear, and symptoms. A canalith repositioning maneuver was used to treat the BPPV. During postmaneuver instruction, the 21 participants assigned to the restricted group were provided with typical activity restrictions. Twenty-one participants assigned to the nonrestricted group were given no postmaneuver restrictions. Only one participant in the restricted group and two participants in the nonrestricted group were not clear at the one-week follow-up appointment. Results indicated that postmaneuver restrictions do not improve treatment efficacy.

Differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV).

This article presents an approach to differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV). Such an approach is essential because of the difference in intervention between the two disorders in question. Results from evaluation of the case study presented here revealed a persistent ageotropic positional nystagmus consistent with MPV or a cupulolithiasis variant of HC-BPPV. The patient was treated with liberatory maneuvers to remove possible otoconial debris from the horizontal canal in an attempt, in turn, to provide further diagnostic information. There was no change in symptoms following treatment for HC-BPPV. This case was diagnosed subsequently as MPV, and the patient was referred for medical intervention. Treatment has been successful for 22 months. Incorporation of HC-BPPV treatment, therefore, may provide useful information in the differential diagnosis of MPV and the cupulolithiasis variant of HC-BPPV.

Prevalence of vestibulopathy in benign paroxysmal positional vertigo patients with and without prior otologic history.

The purpose of this study was to determine the prevalence of reduced or absent labyrinthine reactivity (vestibulopathy) in two groups of participants with posterior canal BPPV. One group had prior diagnosis of otologic disease (positive history group). No one in the second group had ever been diagnosed with otologic disease (negative history group). Caloric responses were retrospectively analyzed for the two groups. Patients with a positive history exhibited a greater prevalence of vestibulopathy than patients with a negative history. The positive history group, on average, also exhibited a larger unilateral weakness than those patients in the negative history group. We conclude that patients with BPPV and a history of otologic disease are more likely to present with vestibulopathy, than patients with BPPV and no history of otologic disease. This finding supports the benefit of complete vestibular evaluation in patients with BPPV to ensure comprehensive and successful treatment outcome.