Before performing any vestibular test, taking a thorough medical history and ascertaining the patient's symptoms constitute the first steps in caring for a patient with a vestibular disorder. Sometimes the patient history alone may suggest a diagnosis.
Taking a patient history should include determining the patient's symptoms, including balance, hearing, vision, somatosensation, and motor function. The first task for a neurotologist is to allow the patient to describe what he or she senses. The clinician may help the patient in choosing the correct terms to describe his complaints.
Vertigo can be described as an unreal sense of rotationary movement. It should be distinguished from dizziness, which describes any kind of altered sense of orientation. A history of vertigo is of great value in identifying the presence of vestibular pathology but not in localizing its origin. Vertigo results from impaired tonic symmetry in the inputs of the vestibular nuclei. Therefore, a vestibular lesion can occur anywhere within the vestibular end-organs, the vestibular nuclei, the cerebellum, the pathways connecting these structures in the brainstem, and, rarely, within the cortex.
The differentiation between peripheral and central nervous system (CNS) lesions may be based on detailed features of vertigo, even though these features may not apply to every patient. The clinician should determine whether the vertigo occurs in episodes or continuously. If it is episodic, it should be ascertained how often the episodes occur and how long they last. In peripheral causes, vertigo occurs in episodes with an abrupt onset. It disappears in varying time periods, from seconds to days, based on the underlying pathology. The origin of intensive, episodic vertigo that lasts up to a minute is more likely benign paroxysmal positional vertigo (BPPV) if it is provoked with particular positions. Another cause of brief but recurrent vertigo or dizziness, especially if precipitated by body straining, is perilymph fistula. Vertigo that lasts 2–20 minutes is consistent with a transient ischemic attack, which affects the posterior circulation if it is associated with visual deficits, ataxia, and localized neurologic findings. Meniere disease causes recurrent vertigo attacks that can last between 20 minutes and 24 hours. An isolated attack of vertigo that lasts more than 24 hours is suggestive of vestibular neuronitis. Autonomic symptoms such as nausea, vomiting, and sweating are common presenting symptoms. Generally, the more intense symptoms a patient has, the more likely it is that the vertigo is caused by a peripheral lesion.
Lightheadedness describes the sensation of unsteadiness and falling or the symptoms similar to those preceding syncope, such as blurred vision and faded facial color. It should be distinguished from both vertigo and visual disorientation. Most often, lightheadedness occurs with nonvestibular causes such as cardiac or vasovagal reflex.
Imbalance is described as the inability to maintain the center of gravity. ...