Audiology News

State of Kuwait

ICS Impulse vHIT

The video head impulse test (vHIT) is a useful clinical tool to detect semicircular canal dysfunction. ICS Impulse is the world’s first vHIT device with studies supporting its ICS-impulse-3accuracy, speed in testing and unrivaled patient comfort. Fast, simple and precise, ICS Impulse is now recommended as the first step in analysis, helping to improve workflow and patient care. Some of the advantages of the ICS Impulse vHIT are:

1. ICS Impulse provides precise, accurate data based on real-life stimuli. The high-frequency stimuli used in HIT is similar to that used in daily activity that occurs when crossing the street, sitting in a restaurant or quickly turning to a sound

2. Head Impulse test is the only test available to assess all six semicircular canals (lateral, anterior, and posterior).

3. ICS Impulse increases test quality by displaying head velocities which assists in the performance of unpredictable head impulses. Training curves provide a guide to assist you in performing quality head impulses of varying velocities.

4. Superior Pupil detection provides error free data. Calibration can be performed anywhere using Impulse goggles with built-in lasers. All you need is a small surface for which to project the laser dots. In seconds, you are ready to test.

5. View analysis in 2D or 3D. Both display a gain graph with built-in published normative data. A clear 3-D picture facilitates easy identification of saccades. Comparison of test sessions allows for validation of vestibular rehabilitation success.

6. Due to the sophisticated cameras smaller velocity head impulses of only 15 to 20 degrees are used, making the test more pleasant for the patient.

7. ICS Impulse detects more abnormalities than visual observation and reduces false negatives.

Clinical Significance

This video method of recording eye movements during vertical head impulses provides evaluation of vertical semicircular canal function in patients in a clinical setting, even at the bedside.The non-invasive and short (about 10–15 min) nature of vHIT also facilitates follow-up examinations to document recovery of patients e.g. after vestibular neuritis.

vHIT allows the physician to refine the clinical diagnosis and determine whether the entire vestibular nerve is affected, or just branches of it. Vestibular neuritis, for example, can affect the superior vestibular nerve, damaging the anterior and lateral canal, the inferior vestibular nerve, damaging only the posterior canal, or both. So involvement of both the anterior and lateral canal confirms the diagnosis of ‘classic’ superior vestibular neuritis. Evidence of isolated loss of posterior canal function, on the other hand, confirms the diagnosis of inferior vestibular neuritis, differentiating this condition from a central vestibular disorder. Furthermore, the method helps evaluating superior canal function in patients with superior canal dehiscence or confirming posterior canal occlusion after surgery for intractable benign paroxysmal positional vertigo. Combined with the vestibular evoked myogenic potential testing (VEMP) for otoliths, it means that the function of all vestibular sense organs can now be tested.