Assessment of vertigo.

Vertigo is defined as a subjective sense of imbalance and includes unsteadiness as well as a sensation of rotation. Vertiginous symptoms may arise from defects in the labyrinth, the visual system, or the central nervous system, although in most patients presenting with balance problems, the lesion lies within the labyrinth or its central connections. The most important step in the diagnosis is an unhurried and detailed history, bearing in mind that many patients will have difficulty in describing their symptoms. A detailed neurological examination is usually unnecessary but one must examine the ears, cranial nerves, cerebellum, and balance function, and look for the presence of nystagmus. The common error of carrying out investigations in place of a detailed history is to be avoided. In many cases, investigations are not required at all, although it is the author's practice to do a routine pure tone audiogram with basic assessment of speech discrimination. There is no indication for routine caloric testing, imaging or blood analysis, each of which should be carried out only when there are specific indications. In the routine clinical care of patients, it is only in exceptional situations that specialised vestibular testing is required, although these are often necessary in research projects.