| DIZZINESS
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Injury 101 ]
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.
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