Magnetic resonance imaging results in patients with central electronystagmography findings

Do central vestibular findings predict abnormal findings on magnetic resonance imaging?

Objective

To determine whether central findings from vestibular tests predict abnormal findings on magnetic resonance imaging.

Method

This study was a retrospective case series at a tertiary referral centre. The main outcome measure of this diagnostic intervention study was the positive predictive value of central vestibular findings in relation to magnetic resonance imaging abnormalities.

Results

Central vestibular findings had a 50.9 per cent positive predictive value for magnetic resonance imaging abnormalities across all age groups although they varied according to age group. Optokinetic nystagmus (p < 0.05) and abnormal findings on videonystagmography tests (p < 0.05) were the main predictors of magnetic resonance imaging abnormalities. White matter lesions constituted the bulk of the central lesions on magnetic resonance imaging followed by cortical and cerebellar atrophy.

Conclusion

Central vestibular findings had a 50.9 per cent positive predictive value for magnetic resonance imaging abnormalities across all age groups. Magnetic resonance imaging is medically justified to further evaluate patients with central findings on vestibular studies. Therefore, it is reasonable to request magnetic resonance imaging in these patients.

Central vestibular dysfunction in an otorhinolaryngological vestibular unit: incidence and diagnostic strategy

Introduction Vertigo can be due to a variety of central and peripheral causes. The relative incidence of central causes is underestimated. This may have an important impact of the patients' management and prognosis. Objective The objective of this work is to determine the incidence of central vestibular disorders in patients presenting to a vestibular unit in a tertiary referral academic center. It also aims at determining the best strategy to increase the diagnostic yield of the patients' visit. Methods This is a prospective observational study on 100 consecutive patients with symptoms suggestive of vestibular dysfunction. All patients completed a structured questionnaire and received bedside and vestibular examination and neuroimaging as required. Results There were 69 women and 31 men. Their ages ranged between 28 and 73 (mean 42.48 years). Provisional videonystagmography (VNG) results were: 40% benign paroxysmal positional vertigo (BPPV), 23% suspicious of central causes, 18% undiagnosed, 15% Meniere disease, and 4% vestibular neuronitis. Patients with an unclear diagnosis or central features (41) had magnetic resonance imaging (MRI) and Doppler studies. Combining data from history, VNG, and imaging studies, 23 patients (23%) were diagnosed as having a central vestibular lesion (10 with generalized ischemia/vertebra basilar insufficiency, 4 with multiple sclerosis, 4 with migraine vestibulopathy, 4 with phobic postural vertigo, and 1 with hyperventilation-induced nystagmus). Conclusions Combining a careful history with clinical examination, VNG, MRI, and Doppler studies decreases the number of undiagnosed cases and increases the detection of possible central lesions.

Evaluation of patients with vertigo of vertebrobasilar insufficiency origin using auditory brainstem response, electronystagmography, and transcranial Doppler

OBJECTIVES

Vertigo can be a manifestation of underlying vertebrobasilar stroke in older adults. The study objectives were to investigate the correlation, sensitivity, and specificity of the auditory brainstem response (ABR), electronystagmorgraphy (ENG), and transcranial Doppler (TCD) collectively to distinguish between vertigo due to vertebrobasilar insufficiency (VBI) and vertigo due to non-VBI.

DESIGN

Prospective experimental study comparing ENG, ABR, and TCD battery findings between two groups of patients with vertigo and a control group.

STUDY SAMPLE

Participants included 14 patients with vertigo of VBI origin, 14 patients with vertigo of non-VBI, and 11 matched controls.

RESULTS

Participants with VBI had more abnormal findings in the ENG (86%), TCD (72%), and ABR (64%) compared to the non-VBI group (64%, 21%, and 7%, respectively) and the control group. The combined battery revealed positive correlations, 64% sensitivity, and 84% positive predictive value (PPV) in the VBI group, and 100% specificity with lack of correlations in the non-VBI group.

CONCLUSIONS

The modest sensitivity and PPV helps with early detection of VBI, thus preventing risk of vertebrobasilar stroke in 84% to 64% of patients. The 100% specificity in the non-VBI group rules out VBI, thus reducing the referral rate for unnecessary, diagnostic evaluations and ineffective treatment.

Relative diagnostic importance of electronystagmography and magnetic resonance imaging in vestibular disorders

OBJECTIVE

The aim of this study was to investigate the contribution of electronystagmography and magnetic resonance imaging to the aetiological diagnosis of vertigo and unsteadiness, in a population in which the history and clinical examination provide no conclusive diagnosis of the origin of the dysfunction (i.e. peripheral or central).

PATIENTS AND METHODS

This retrospective study included 102 patients, who underwent full ENT clinical evaluation, history and neurotological assessment (including pure tone audiography, auditory brainstem response testing, electronystagmography and magnetic resonance imaging).

RESULTS

Electronystagmography contributed to establishment of a diagnosis in 53/102 patients (52 per cent), whereas magnetic resonance imaging did the same in four of 102 patients (3.9 per cent).

CONCLUSION

Electronystagmography remains the most useful examination for aetiological diagnosis of patients with vertigo and unsteadiness, since the actual number of patients with vertigo and unsteadiness of central origin is small (3.9 per cent), even in a population in which history and clinical examination may indicate an increased probability of central nervous system dysfunction.

Evaluation of vertigo by auditory brain stem response

The authors examined the hypothesis that abnormal patterns of the auditory brain stem response (ABR) could supplement the neuro-otological evaluation and assist in localizing the site of vestibulocerebellar dysfunction. This project is based upon the fact that the sources of waves I through V have been regionally identified. Absent or delayed patterns can be referenced to the normal data, and the site of a lesion generating vertigo can be established. We found absence of waves or prolonged interpeak latencies in 25% of the vertiginous subjects with normal hearing and magnetic resonance images of the brain. We conclude that in selected cases, lesions affecting the vestibular system can influence the ABR, and the electrophysiological tests of audition may suggest regionalization of the dysfunction in the hindbrain and midbrain.