Our experience with 500 patients with benign paroxysmal positional vertigo: Reexploring aetiology and reevaluating MRI investigation

Objective

To explore the aetiology of and to evaluate the importance of MRI investigation on the posterior semicircular canal benign paroxysmal positional vertigo in an Irish population.

Methods

A retrospective observational study of 500 patients with posterior semicircular canal benign paroxysmal positional vertigo, diagnosed and treated by the senior author over a 10-year period. Most patients underwent an MRI brain and inner ear, following the same scan protocol. This included T1 weighted sagittal IR-FSPGR volume, axial T2 weighted, gradient echo T2 weighted and FLAIR sequences plus time of flight cerebral angiography.

Results

The average age of presentation was 56 years; with the overall female to male ratio was 1.6:1, which was largely the net results of 2 age groups. Over 30% of our patients recalled distinct aetiological triggers, of which the top 3 were trauma, infection, and surgery. These accounted for 16%, 6%, and 5%, respectively. More than 25% of the patients were discovered to have abnormal intracranial findings on MRI. The 2 most common non-infarct incidental findings were neoplasia and vascular abnormalities. Although fewer than 20 patients had acute intracranial haemorrhage or malignant tumours, most of them were urgently referred to neurosurgeon due to the life-threatening nature of the condition. One round of particle repositioning manoeuver was successful in treating 84% of the patients, and the 2-year recurrence rate was only 2.2%.

Conclusion

The diagnosis of posterior semicircular canal benign paroxysmal positional vertigo is thought to be relatively easy to make, and the treatment is highly effective. Clinicians should be fully aware of and prepared for the diverse aetiology, and thus have no hesitation in requesting MRI scan as an important investigation.