Vestibular Consequences of Concussion/TBI Flashcards
What is a concussion?
A type of traumatic brain injury (or TBI) caused by a bump, blow, or jolt to the head or by a hit to the body that causes the head and brain to move rapidly back and forth
This sudden movement can cause the brain to bounce around or twist in the skull, creating chemical changes in the brain and sometimes stretching and damaging brain cells
When can concussions occur?
Head strike another object
Fall w/ contact ground
Quick acceleration/deceleration w/o head contact (whiplash)
More severe concussions caused by indirect blows where brain sustains more rotational sheer force leading to more severe symptoms
Can nerve signals in the brain be disrupted for months after a single concussion?
Yes
During this time frame, people are more likely to have a secondary injury
Can get cascades of cellular changes or death
Can trauma to the brain affect the vestibular system?
Yes
Causing abnormal signals regarding position and movement of the head in space (CNS or labyrinthine dysfunction (trauma to the inner ear) or mixed)
Do concussions signs often appear on a CT or MRI?
No
There is no standard diagnostic test for concussion
Diagnosis is based upon a group of symptoms or signs that may be immediately present or arise over weeks after
Some people however, develop no symptoms at all after a concussive event and some take weeks
What are some common symptoms of concussions?
Difficulty thinking clearly
Feeling slowed down
Difficulty concentrating
Difficulty remembering new information
Headache
Fuzzy or blurry vision
Nausea or vomiting (early on)
Dizziness
Sensitivity to noise or light
Balance problems
Feeling tired, having no energy
Irritability
Sadness
More emotional
Nervousness or anxiety
Sleeping more than usual
Sleeping less than usual
Trouble falling asleep
Is there currently ongoing research that attempts to determine the best way to diagnose concussion?
Yes
And when a person is cleared to return to activity (like sports)
Are there a lot of common symptoms between concussion and vestibular disorders?
Yes
What are some current ways to assess concussion?
Tests of oculomotor function
Subjective Self-Report Measures: Dizziness Handicap Inventory (DHI), Vertigo handicap questionnaire, Vestibular Disorders Activities of Daily Living Scale
Postural Stability / Gait (BESS, CTSIB, SOT, Tandem Gait)
Usually a neuro or cognitive related assessment
Do the incidences of vestibular abnormalities stay constant regardless or severity of head injury?
Yes
Did most patients have vestibular findings after head injury?
Yes
Some had central findings
What vestibular pathology can mimick concussion?
BPPV, labyrinthine concussion, perilymphatic fistula
How do we differentiate TBI and vestibular etiology?
Common Vestibular Symptoms (uncommon in TBI):
Vertigo as opposed to dizziness
Positionally-evoked dizziness
Changes in hearing
Onset of Tinnitus (ringing in ear) - people with head injury can also develop this, but it’s more common in vestibular etiology
Presence of spontaneous nystagmus
VOR deficiencies (vHIT) - corrective saccades
Is there a growing body of research regarding the incorporation of vestibular assessments into initial concussion evaluations?
Yes because many vestibular abnormalities share common symptoms with concussion
May not actually be TBI
Neurophysiologic tests may be more objective than neuropsychological tests in diagnosing concussion because the latter partly rely on patient input (susceptible to bias)
Neurophysiologic tests may help localize lesion when CT, MRI or other imaging are ‘normal’
Can vestibular therapies be an effective rehab tool for concussion/TBI?
Yes
So proper assessment is crucial for therapy and for documentation of progress
Are there new oculomotor subtests on the horizon specifically aimed at increasing efficacy for diagnosing concussion/mTBI?
Yes
3-D torsional tracking oculography (vergence abnormalities)
Saccadometry (predictive saccades, anti-saccades - make the equal and opposite eye movement; look left when the dot moves right)
System judges the accuracy of the metric (error rate) and how fast they can do that
*Someone with TBI will make more accuracy errors and will take longer
*These metrics will be on the new systems
