Recovery from unilateral vestibular nerve section in human subjects evaluated by physiological, psychological and questionnaire assessments

Measuring outcome from Vestibular Rehabilitation, Part I: Qualitative development of a new self-report measure

Research suggests that Vestibular Rehabilitation (VR) is an effective treatment for dizziness, but there is currently no measure specifically designed to assess treatment outcome. A review of existing self-report measures of dizziness indicates that no measure has been designed for longitudinal application and all suffer from limitations which restrict their usefulness in measuring VR outcome. A need for a psychometrically robust patient-oriented measure of quality of life benefit from VR is identified. The aim of the present study was to explore dimensions relevant to VR with a view to developing a measure of outcome. Eighteen adults receiving VR participated in interviews about the quality of life impact of dizziness. Qualitative analysis revealed 64 themes describing self-perceived quality of life impact. Themes were developed into potential questionnaire items and 35 were selected to represent the quality of life impact of dizziness in a prototype questionnaire. A quarter of items in the prototype questionnaire refer to issues not addressed by existing measures; the remaining items draw together issues covered by the range of questionnaires currently in use.

Literature review of questionnaires assessing vertigo and dizziness, and their impact on patients' quality of life

OBJECTIVES

Vertigo and dizziness, which are major symptoms of diseases affecting the vestibular system, drastically impair patients' health-related quality of life (QoL). Patient's perspectives are thus essential to symptom assessment. We sought to make a critical review of published questionnaires measuring vertigo or dizziness, and/or their impact on QoL.

METHODS

Twenty-nine articles reporting the validation or use in clinical trials of vertigo- or dizziness-specific questionnaires were identified over the 1991-2004 period, and reviewed using a methodological and a Patient-Reported Outcomes specific checklist. Questionnaires were classified into three categories according to content: QoL (or handicap), mixed (assessing both symptoms and QoL), and symptom questionnaires.

RESULTS

Four QoL, three mixed questionnaires, two symptoms, and one Meniere's disease-specific questionnaire were identified. QoL questionnaire validation was usually not complete. The structural validity of the Dizziness Handicap Inventory is not established, although this questionnaire is considered to be the reference questionnaire in the QoL domain. Moreover, QoL questionnaires were not very specific to vertigo or dizziness. Similarly, the Vertigo Handicap Questionnaire appeared to have the most pertinent content, but its validation remains to be completed. Mixed questionnaires have the same imperfections. The Vertigo, Dizziness, Imbalance (VDI) Questionnaire had the best validation score from the checklist, but its responsiveness appears to be weak. Regarding symptom questionnaires, the European Evaluation of Vertigo questionnaire evaluated the five major symptoms of vestibular syndrome satisfactorily.

CONCLUSION

The present literature review failed to find any relevant and validated questionnaire assessing the impact of vertigo or dizziness on QoL.

Neuro-otological emergencies

PURPOSE OF THE REVIEW

Physicians find acute vertigo a diagnostic challenge. This article review recent evidence outlining the clinical presentation of acute central and peripheral dizzy syndromes and suggest when clinicians may consider acute neuro-imaging.

RECENT FINDINGS

Recent evidence highlights the difficulty that acute vertigo may sometimes pose to the clinician. For example, migrainous vertigo may have oculomotor abnormalities suggestive of either central neurological or peripheral vestibular dysfunction. Furthermore, vertebrobasilar stroke syndromes may mimic peripheral disorders such as vestibular neuritis, or when there is hearing involvement may be misdiagnosed as Meniere's disease. In addition to the need for identifying serious conditions in acute vertigo, recent evidence suggests that early steroid treatment in vestibular neuritis may improve long term outcome. Further trials regarding symptomatic outcome are required, however, before routine use of steroids can be recommended in this condition.

SUMMARY

Recent findings have not made the assessment of acute vertigo any easier for the nonspecialist. Although the commonest vertigo syndromes are benign, serious conditions such as stroke may masquerade as a peripheral labyrinthine disorder and conversely benign conditions such as migrainous vertigo may have clinical characteristics of central disorders. These findings re-emphasize the need for a thorough clinical evaluation of the acutely dizzy patient.

The relationship between the activities-specific Balance Confidence Scale and the Dynamic Gait Index in peripheral vestibular dysfunction

BACKGROUND AND PURPOSE

People with vestibular dysfunction experience dizziness, vertigo and postural instability. The persistence of these symptoms may result in decreased balance confidence. The purpose of the present study was to examine the relationship between decreased balance confidence and gait dysfunction in patients with unilateral peripheral vestibular dysfunction.

METHOD

A retrospective review of 137 charts with the Activities-specific Balance Confidence (ABC) Scale and the Dynamic Gait Index (DGI) scores was completed. Spearman rank-order correlation analysis was performed of the total sample, by age group and by degree of vestibular weakness.

RESULTS

A moderate correlation of r = 0.58 (p < 0.001) was found between the ABC Scale score and the DGI score in the total sample. Those with mild or moderate vestibular weakness had a correlation of r = 0.72 (p < 0.001) between the ABC Scale score and the DGI score, compared with a correlation of r = 0.48 in those with severe or total vestibular weakness.

CONCLUSIONS

Decreased balance confidence and increased fall risk are critical issues for people with vestibular dysfunction. The effects of aging did not have a significant impact on the relationship. The correlation between balance confidence and gait dysfunction was stronger in those with mild or moderate vestibular weakness, although those with severe or total weakness were more disabled by their vestibular symptoms.

Vestibular effects of cochlear implantation

OBJECTIVES/HYPOTHESIS

Cochlear implantation (CI) carries with it the potential risk for vestibular system insult or stimulation with resultant dysfunction. As candidate profiles continue to evolve and with the recent development of bilateral CI, understanding the significance of this risk takes on an increasing importance.

STUDY DESIGN

Between 1997 to 2001, a prospective observational study was carried out in a tertiary care medical center to assess the effects of unilateral CI on the vestibular system.

METHODS

Assessment was performed using the dizziness handicap inventory (DHI), vestibulo-ocular reflex (VOR) testing using both alternate bithermal caloric irrigations (ENG) and rotational chair-generated sinusoidal harmonic accelerations (SHA), and computerized dynamic platform posturography (CDP) at preoperative, 1-month, 4-month, 1-year and 2-year postimplantation visits. CI was carried out without respect to the preoperative vestibular function test results.

RESULTS

Specifically, 86 patients were entered into the study after informed consent. For the group as a whole, pair wise comparisons revealed few significant differences between preoperative and postoperative values for VOR testing (ENG and SHA) at any of the follow-up intervals. Likewise, DHI testing was also unchanged except for significant reductions (improvements) in the emotional subcategory scores at both the 4-month and 1-year intervals. CDP results demonstrated substantial improvements in postural sway in the vestibular conditions (5 and 6) as well as composite scores with the device "off" and "on" at the 1-month, 4-month, 1-year, and 2-year intervals. Device activation appeared to improve postural stability in some conditions. Excluding those patients with preoperative areflexic or hyporeflexic responses in the implanted ear (total [warm + cool] caloric response <or= 15 deg/s), substantial reductions (>or=21 deg/s maximum slow phase velocity) in total caloric response were observed for 8 (29%) patients at the 4-month interval. These persisted throughout the study period. These changes were accompanied by significant low frequency phase changes on SHA testing confirming a VOR insult. Of interest, no significant changes were detected in the DHI or CDP, and there were no effects of age, sex, device manufacturer, or etiology of hearing loss (HL) for these patients.

CONCLUSIONS

Unilateral CI rarely results in significant adverse effects on the vestibular system as measured by the DHI, ENG, SHA, and CDP. On the contrary, patients that underwent CI experienced significant improvements in the objective measures of postural stability as measured by CDP. Device activation in music appeared to have an additional positive effect on postural stability during CDP testing. Although VOR testing demonstrated some decreases in response, patients did not suffer from disabling vestibular effects following CI. The mechanism underlying these findings remains speculative. These findings should be considered in counseling patients about CI.

[Nystagmographic findings in pontocerebellar angle tumors]

OBJECTIVE

To determine the diagnostic and prognostic value of vestibular function tests in cerebellopontine angle tumors

METHODS

Analysis of preoperative nystagmographic findings in 29 patients affected of cerebellopontine angle tumors and its possible correlation with anatomical and progressive patterns

RESULTS

Tumor size and growth pattern were statistically significantly related to auditory and vestibular functions and to central findings on nystagmography. Age, gender, tumor size and central findings on nystagmography did not show influence upon postoperative dysbalance. However, alterations related with adaptation of the vestibular system (positional nystagmus and asymmetry on rotational tests) correlated significantly with postsurgical dysbalance.

CONCLUSIONS

The tests for vestibular function reflect a the characteristics of growth of the cerebellopontine angle tumors and can help to identify the patients susceptible of prolonged postoperative dysbalance.

Outcomes in vestibular ablative procedures

OBJECTIVE

To assess dizziness handicap and postural recovery in 17 patients undergoing a vestibular ablative procedure.

STUDY DESIGN

Outcomes were compared between nine patients who underwent selective vestibular neurectomy and eight patients who underwent a transmastoid labyrinthectomy.

SETTING

Patients underwent ablative procedures at a tertiary care facility.

METHODS

Patients were tested with posturography (sensory organization test [SOT]) and the Dizziness Handicap Inventory (DHI) before and 4 to 5 weeks after their procedure.

RESULTS

The mean change scores for each of the DHI subscales and the total DHI score showed significant improvement for the labyrinthectomy group. For the neurectomy group, only the emotional DHI subscale change score showed significant improvement. No difference was noted between preprocedure and postprocedure SOT scores for either group. The results indicated that the largest proportion of significant correlations existed between DHI and the somatosensory and vestibular subtests of platform posturography. In regression analyses, a model with age (p = 0.04) and vestibular score (p = 0.001) fitted the data well and explained 52.9% of the variance. Persons who were less than 69 years old were three times more likely to report persistent episodes of dizziness after the ablative procedure, and those who had neurectomies were 2.3 times more likely to report episodes of dizziness than those who underwent transmastoid labyrinthectomy.

CONCLUSION

Dizziness handicap after an ablative procedure is influenced by the type of procedure (labyrinthectomy versus neurectomy), age, and preoperative vestibular score on the SOT. Preoperative vestibular SOT score is highly associated with the emotional, physical, and functional domains of perceived handicap and quality of life after the surgery.

Neuro-otologic history

Throughout medicine, the clinical history is the most important diagnostic tool. This is particularly true in vestibular disease, where pathologic confirmation of the disease process is rare. Many vestibular conditions are more appropriately called syndromes, rather than diseases, because the pathology is either variable or unknown. Knowledge of the anatomy and physiology provides the basis of understanding the control of balance and the symptoms that might occur should something go wrong. History taking should cover the elements of the balance system, including vestibular function, vision, hearing, somatosensation, and motor function.

Relationship between physical and psychosocial dysfunction in Mexican patients with vertigo: a cross-cultural validation of the vertigo symptom scale

The Vertigo Symptom Scale (VSS) was designed to assess and differentiate symptoms of: (a) balance disorder; and (b) somatic anxiety and autonomic arousal in patients complaining of dizziness and vertigo. Although it has been translated for use in countries other than the UK, where it was originally developed, its validity in different languages and cultures has not previously been evaluated. This study examined the structure, reliability, and discriminative power of a Spanish translation of the VSS administered to a Mexican sample of 172 dizzy patients and 40 healthy controls. Scores on the two subscales of the VSS not only discriminated between patients and controls, but were also sensitive to differences between patient groups classified on the basis of diagnosis, test results, and occupational disability. The pattern of intercorrelations between symptoms, anxiety, depression, and handicap in the Mexican sample was almost identical to that observed in the original UK sample.

The Role of Vestibular Nerve Section in Meniere's Disease

The role of vestibular nerve section (VNS) surgery in the management of Meniere's disease is considered by prospective analysis of a large series of 531 patients treated by the author over a period of 11 years. Twenty-seven percent were referred by their primary care physicians, while the rest were secondary (45.6%) or tertiary (27.3%) referrals. Overall, 62 (11.7%) Meniere's patients underwent 63 VNS procedures. This surgery was undertaken more frequently in the secondary and tertiary referral patients (14.2%) than in the primary referrals (5.5%). The retrolabyrinthine technique was the preferred approach in almost 90% of ears. The results and complications of these and other surgical options are discussed in an attempt to define the present role of VNS in intractable Meniere's disease. Vertigo was abolished after VNS in 93% of cases. Compensation was significantly impaired in 12.9%. All these patients had contralateral Meniere's disease or marked labyrinthine hypofunction. Although highly effective and associated with few postoperative complications, VNS is generally reserved for sac failures, though may be appropriate as a primary procedure in severe unilateral cases.

The outcome of vestibular nerve section for intractable vertigo: the patient's point of view

To document the outcome of vestibular nerve section from the patient's point of view we reviewed 102 patients who had undergone vestibular nerve section 1 to 10 years after operation. Only 3 patients had experienced further vertigo attacks: 2 of these were cured by a further, this time translabyrinthine vestibular nerve section; 1 patient developed multiple sclerosis. In contrast, about 50% of patients developed some subjective problem with balance while standing or walking; in 15% it was present all the time and of moderate severity. Despite this, over 85% of patients reported that they felt much better or back to normal after the operation and were satisfied with the outcome. The development and application of objective preoperative measures of vestibular and, in particular, vestibulospinal function might improve patient selection for vestibular nerve section and thus reduce the number of dissatisfied patients.

Investigations of disorders of balance

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