Following a TBI complaints of dizziness are very common for a period of days or weeks. Sometimes the dizziness lasts for months. Sometimes it never goes away. When physicians speak of “dizziness,” they generally mean “positional vertigo” (having the room spin or tilt with a change in head position) rather than lightheadedness (from anxiety or low blood pressure) or dysequilibrium (postural abnormalities with imbalance).
A blow to the head can cause dizziness by stretch injury to the vestibulo-cocchlear nerve; inflammation of the membraneous tissue of the labyrinth of the inner ear accompanied by hearing loss or nystagmus (called labyrinthine concussion); physical displacement of the calcified ear stones (otoliths) which sit atop the hair cells in the utricle of the inner ear, causing them to migrate into other parts of the ear; cerebellar damage; brainstem damage; or cervical injury (called cervical vertigo).
Brainstem damage causing vertigo comes from diffuse axonal injury, which cannot be visualized on structural imaging. About one third of all migraine patients experience vertigo with their headaches. Post-traumatic migraine is no different, and our office has clients with PTM combined with vertigo.
With severe head trauma dizziness can arise from temporal bone fracture with bone or blood invading the ear canal. When blood gets inside the inner ear it can cause scarring with fluid blockage, a condition known as hydrops or post-traumatic Meniere’s Syndrome that is accompanied by dizziness with noises in the ear, fullness or hearing changes. Severe head trauma can cause perilymph fistula, a blow-out of the membrane between the inner and middle ear. Someone with this condition is likely to become dizzy upon hearing loud noise (Tullio’s phenomenon). People with perilymph fistula can provoke dizziness by straining or blowing the nose. If the head trauma is severe enough it will trigger the death of hair cells in the cochlea, and cause impairment of hearing in direct proportion to the number of hair cells killed (all the way from mild hearing loss to total deafness).
Diagnosis of post-traumatic vertigo is made by taking a history of onset and symptoms; by visual examination of the inner ear; by a pressure sensitivity test for perilymph fistula; by a hearing test (audiogram); by a tilt table test (to check cardiac output); caloric test (squirting ice water into the ear); by electronystagnogram, by platform posturography and other means. Persistent dizziness can be disabling. It is vital to tell your doctor about your dizziness and make sure you get tested if it does not go away. You can help your doctor diagnose the precise cause of your post-concussional dizziness by keeping a journal noting down which activities or events trigger it.
For some patients only aerobics, jogging or other activities which jostle the head bring it on. For others the dizziness is relatively constant. Dizziness can also accompany post-traumatic headaches, especially post-traumatic migraine, which produces transient increases in the diameter of brain arteries with diminished blood flow and blood pressure. Treatment typically involved medication, changes in lifestyle (such as activity restrictions), physical therapy and more rarely surgery.