Vestibular Dysfunction

Vestibular dysfunction is a disturbance of the body's balance system. Etiologies of this disorder are broadly categorized into peripheral and central causes based on the anatomy involved. The symptoms of peripheral and central vestibular dysfunction can overlap, and a comprehensive physical examination can often help differentiate the two. Vestibular disorders usually present acutely, and the most common form of acute peripheral vestibular dysfunction is benign paroxysmal positional vertigo (BPPV).

The most common cause of severe central vestibular dysfunction is an ischemic stroke of the posterior fossa, which contains the brainstem and cerebellum. Acute ischemic stroke accounts for up to 25% of patients who present with central vestibular dysfunction. Since acute stroke is treated differently from other causes of disequilibrium, it is essential to recognize this process promptly. Vertebrobasilar artery disease can lead to stroke in 5% of patients, and patients with this condition often present initially with syncopal episodes and/or vestibular dysfunction. The second most common cause of central vestibular dysfunction is a demyelinating disease.

Symptoms of vestibular dysfunction include a variety of complaints: vertigo, nausea and vomiting, intolerance to head motion, spontaneous nystagmus, unsteady gait, and postural instability. The prevalence of each of these symptoms varies, and there is no single symptom that is pathognomonic for vestibular dysfunction. The presentation of these symptoms as a cluster should raise the level of clinical suspicion for vestibular dysfunction. A complete history and physical examination is the best way to differentiate peripheral from central vestibular dysfunction.

Identifying which type of vestibular dysfunction a patient has is crucial, as this determines the therapeutic approach and the urgency of initiating treatment. The mainstay of treatment for peripheral vestibular disorders is symptomatic therapy, but the treatment for central vestibular dysfunction caused by an ischemic stroke can include emergent intravenous thrombolytic therapy and interventional clot retrieval. Early identification of demyelinating disorders, such as multiple sclerosis, is essential so that treatment can be initiated to prevent the rapid decline and development of disability.

This article will review the epidemiology, history and physical examination, evaluation, differential diagnosis, treatment, complications, and critical points in diagnosing and managing vestibular dysfunction and differentiating peripheral from central vestibular disorders.