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Frequently Asked Questions Computerized Dynamic Plate Testing:

 

• What is a Computerized Dynamic Plate testing? • Who should be balance tested?  VNG Testing :

 

• Does the VNG test cause any side effects?

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• How long does it take to get the VNG test results back?

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• How long does a VNG test take from start to finish?

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• What is a VNG test?

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• What is a Balance test?

 

 The Computerized Dynamic Plate test is an agility and balance (equilibrium) test.

 

   Who should be balance tested?

 

Every adult patient over the age of 50 should be screened by taking a subjective self-assessment balance questionnaire. If the patient has a positive screening, then the next step is a Computerized Dynamic Plate test, and/or a Videonystagmagraph (VNG) test.

 

   Does the VNG test cause any side effects?

 

   Some individuals become dizzy for 2-3 minutes, but most are able to drive home after the test without difficulty. (See Patient Consent Form)

 

   How long does it take to get the VNG test results back?

 

 Once the test is done the report will be read by one of our Otolaryngologists/Neuro -Otologists/Neurologists or Audiologists. The results will be sent back to your office typically within 3-5 business days from the date of the test.

 

   How long does a VNG test take from start to finish?

 

It takes approximately 45 to 60 minutes.

 

   What is a VNG/VAT/CDP complete test?

 

  The patient sits in an armchair or an exam table approximately 50cm from a determined point.

 

   We use an infrared VNG video goggle assembly that does not require the use of electrodes but performs the same tasks with a mini ocular camera that tracks the movement of the patients eyes as they follow the instructions of the technician.

 

   The results of the stimuli are recorded and processed by the computer to be analyzed and interpreted by the physician.

 

   A full history and symptomology is also collected. Smooth Pursuit is tested by having patients keep their head still while smoothly following a moving target with their eyes. Saccades are tested by having patients keep their head still while moving only their eyes from target to target (typically, the target will appear middle, then left, middle, then right, etc). Optokinetic is tested by having patients keep their head still while trying to focus on stripes (targets) that move rapidly across the patients’ field of vision, disappearing on one side and appearing on the other.

 

    In the Vestibular Autorotation Test (VAT) (CPT code 92546, one to six units), minimum of six distinct tests of the VOR is tested by the patient moving his/her head at speeds of between 2-6 Hz in rhythm to an alternating tone while keeping his eyes fixed on a target. Statistical reliability in the VAT requires at least 3 separate horizontal and 3 separate vertical tests to achieve the level of confidence established in the normative data. The VAT is distinct in its measurements, with specific physiologic foundations, providing not only information about differential diagnosis but also site of lesion, allowing it to be used effectively in the diagnosis, treatment plan and objective monitoring of vestibular and balance disorders.

 

    One other test sometimes requested by physicians to verify the VAT result and BPPV is the Caloric test (CPT code 92543, 4 units), usually consisting of four distinct tests stimulating the inner ear system by use of Bithermal Calorics.

 

   Another test confirming a central nervous system or peripheral problem is the Computerized Dynamic Posturography (CDP) test (CPT code 92548). Durations for normative values for eyes opened and eyes closed as well as limits of stability give the physician important information regarding the orientation of the patient for balance and, in future re-tests, measure progress of medical intervention or therapy.

 

   Testing verifies vestibular functioning of the VOR, the Optokinetic system via oscillating horizontal and vertical movements, Gaze, fixation ability and CNS visual-vestibular response. More importantly, the test results aid the physician in referring the patient to the professional who can formulate the best treatment protocols. In most cases, this comprehensive testing eliminates the need for costly CT Scans or MRI’s, and reduces the fall risk potential of the patient