Persistent vertigo and dizziness after mild traumatic brain injury.

Vertigo, dizziness, and disequilibrium are common symptoms following concussion or mild traumatic brain injury (mTBI). Dizziness and vertigo may be the result of trauma to the peripheral vestibular system or the central nervous system, or, in some cases, may be due to anxiety, depression, or posttraumatic stress disorder; these mechanisms are not mutually exclusive. While most peripheral vestibular disorders can be identified by testing and examination, those without inner-ear causes that have persisting complaints of dizziness and motion sickness are more difficult to understand and to manage. Some of these patients exhibit features compatible with vestibular migraine and may be treated successfully with migraine-preventative medications. This paper reviews the nonotogenic causes of persisting dizziness, the possible mechanisms, and the pathophysiology, as a framework for patient management and for future research.