Infrared Video Goggle Positional Test (IRV)
Purpose: To observe and record on videotape any abnormal eye movements which may be consistent with positional vertigo.
Procedure: The patient wears goggles placed over their eyes which are equipped with an infrared video camera and a microphone. The patient is in darkness throughout the testing and is placed on an examination table in various head and body positions. Eye movements and patient instructions are recorded on a video tape. This is a painless test which takes approximately 20 minutes. The patient may experience dizziness in certain positions, however, the dizziness usually subsides quickly.
Posturography
Purpose: To evaluate a patient's ability to maintain balance under various conditions and to identify which system is causing the balance problems.
Procedure: The patient stands in a semi-enclosed space while the floor and visual surroundings are gradually moved. The patient is advised of each upcoming movement. Small sensors under the floor board assist in evaluating how the body responds to various environmental changes. This is a painless test that takes approximately 45 minutes. The patient muse be able to stand unsupported for a short time.
Electrocochleography
Purpose: To evaluate the cochlea's response to sound. ECOG is most often used to confirm the presence of Meniere's Disease.
Procedure: A small monitor is placed in the ear canal, behind both ears and on the forehead. Sound is delivered by earphones while the monitors pick up how the cochlea/auditory nerve respond to sound. Throughout the procedure, the patient rests comfortably. The test is painless, and requires no response from the patient. Test time is approximately 1 hour.
Electroneurography (ENOG)
Purpose: To evaluate the integrity of the facial nerve.
Procedure: Small monitors are placed on the nose and forehead. The patient sits quietly while a stimulator stimulates the facial nerve. The response is recorded on a computer and a comparison is made between the right and left side of the face. ENOG is very fast: actual test time is less than 5 minutes.
Otoacoustic Emissions (OAES)
Purpose: A fast non-invasive method of testing for a cochlear pathology.
Procedure: A small probe containing a speaker and microphone are inserted into the ear canal. An acoustic signal is sent he middle ear into the cochlea where the outer hair cells react by generating and emitting an acoustic signal back where it is detected by the microphone. Testing is completed within several minutes.
Central Auditory Testing
Purpose: Evaluate the status of the auditory system beyond the inner ear to rule out a functional problem processing auditory information.
Procedure: The patient is asked to repeat words or sentences heard through earphones. The information is presented -with background noise, competing information, and filtered speech in an attempt to stress the auditory system. A battery of age appropriate tests are completed. Approximately 2-3 hours are needed to complete the testing.
Visual Reinforcement (VRA)
Audiometry-behavioral testing used with infants to determine the type and severity of hearing loss.
Vestibular Evoked Myogenic Potential (VEMP)
Purpose: Evaluate the presence or absence of semicircular canal dehisence (SCD) which can cause noise induced dizziness.
Procedure: Monitors are placed on the neck muscles and forehead. Soft earphones are inserted into the ear canals. The patient lifts his/her head while in a supine position and also rotates the head to the side. Sounds of varying, but moderate intensities are played in the ears while the patient elevates and rotates the head at one minute intervals. This is a painless test lasting about 30 minutes, however, the patient may experience fatigue of the neck muscles briefly.