Effect of blink reflex in diagnosis of central vertigo and its comparison with brain MRI

Background and Objective: Vestibulitis and VIII nerve lesions are the final diagnosis in most of the patients presenting with acute true vertigo, but central vertigo due to brainstem lesions must always be considered. In most of the patients, brain MRI is the only available solution. In this study, blink reflex (BR) abnormalities in acute true vertigo were compared with MRI findings. Methods: 105 patients who were presented with acute true vertigo without other signs of brainstem involvement, and who had normal neurologic examination were evaluated. In 18 patients in whom new neurologic signs were appeared or their symptoms were lasted for more than 72 hr, BR and brain MRI were requested and their results were compared. Findings: From 18 patients, in 5 patients BR and brain MRI were normal and central vertigo was ruled out. In 8 patients both BR and brain MRI were abnormal. 3 patients had normal BR and abnormal brain MRI. In the last 2 patients, brain MRI was normal but BR was abnormal. Conclusion: Abnormal response of BR (76.9%) were well correlated with abnormal MRI findings (84.6%), and the results of the 2 tests were additive. Therefore, BR can be a good accompaniment for brain MRI in evaluation of central vertigo