Medical Diagnostic Testing And Management Flashcards
- Recording eye movements by using electrodes around the eye
- Uses electrical field changes to estimate the position of eyes (indirect method)
- Used in very small children/babies or when ptosis is present
Electronystagmography
-Recording eye movements by estimating the position of the eyes (direct method)
-Video system where you can observe and record the video of eye movements
-Movements translated into a representation of yaw (horizontal) and pitch (vertical) movements
Videonystagmography
-Oculomotor examination (saccades, smooth pursuits, gaze holding)
-Assessment of nystagmus (spontaneous - fixation removed, headshake nystagmus testing - looking for rebound nystagmus)
-Positional testing (Dix-Hallpike, roll tests)
-Caloric testing
Components of an ENG and VNG tests
-Looks at one peripheral vestibular organ at a time
-Uses camera to measure eye movement
-Only evaluates horizontal canal at low frequency
-Stimulates canal with a change in temperature
Caloric irrigation testing
Cold opposite (inhibits)
Warm same (excites)
COWS
Irrigation with cool on the right results in
Left beating nystagmus (inhibitory)
Irrigation with warm on the right results in
Right beating nystagmus (excites)
Considered clinically significant results from caloric test
25-30% difference between sides (1-24% difference considered normal)
Best test for determining peripheral vestibular deficit (unilateral)
Caloric test
-Can not be used to determine bilateral vestibular loss
-Only evaluates system at a low frequency
Weaknesses of caloric irrigation test
-Gold standard for identifying bilateral vestibular loss
-Expands ability to evaluate vestibular system at higher frequencies
-Used to differentiate between compensated and uncompensated unilateral vestibular loss
Rotary chair testing
- Gain: gives the strength of the response
- Phase: timing of response
- Asymmetry: are both sides working together
What is measured during rotary chair test
Used to quantify balance -> does NOT diagnose and is not specific
Posturography (CDP)
Antivert/Meclizine
Vestibular suppressants used for acute management
Likely to affect vestibular testing (BPPV, VNG)
Possible implications from using vestibular suppressants
Zofran/compazine
Anti-nausea medication that may help to improve early tx tolerance
Anti-anxiety/anti-depressants
Medical intervention used for 3PD and vestibular migraine
Steroid pack
Medical intervention used for acute management of neuritis to decrease inflammation
Vestibular nerve resection, gentamycin injection
Surgical management used for tx of Ménière’s disease
