Head Impulse Test: Understanding the Diagnostic Pathology Test

The Head Impulse Test is a diagnostic procedure used to evaluate the function of the vestibulo-ocular reflex (VOR), which is responsible for stabilizing the eyes during head movements.

During the test, the patient is instructed to fixate on a target while the examiner rapidly rotates their head to one side.

The goal is to assess the ability of the eyes to remain focused on the target despite the sudden head movement.

The vHIT test, also known as video Head Impulse Test, is a modern version of the Head Impulse Test that uses video goggles to record eye movements during head impulses.

This allows for more precise and objective measurements of the VOR function.

The vestibular health evaluation, balance function test, and eye movement testing are all components of the Head Impulse Test that help assess the integrity of the vestibular system and its impact on balance and eye coordination.

What is the Purpose of Performing a Head Impulse Test Test?

The primary purpose of performing a Head Impulse Test is to assess the function of the VOR, which is essential for maintaining clear vision during head movements.

A healthy VOR helps prevent blurred vision and dizziness during activities such as walking, running, or driving.

The test is particularly useful in diagnosing vestibular disorders such as benign paroxysmal positional vertigo (BPPV), vestibular neuritis, and Meniere's disease.

By evaluating the VOR function, healthcare providers can determine the underlying cause of symptoms such as vertigo, dizziness, and imbalance.

In cases of head trauma or neurological conditions, the Head Impulse Test can also provide valuable information about the integrity of the vestibular system and guide treatment decisions.

What are the Costs of Head Impulse Test Tests in India?

The cost of a Head Impulse Test in India can vary depending on the healthcare facility, location, and additional services included in the evaluation. On average, the price range for a vHIT test is between INR 2000 to INR 5000.

Factors that may influence the cost of the test include the expertise of the healthcare provider, the use of advanced technology such as video goggles, and the need for additional consultations or follow-up evaluations.

It is essential to compare prices and services offered by different healthcare providers to ensure that you receive a comprehensive and accurate assessment of your vestibular health.

What is the Normal Range and All Values of Head Impulse Test?

The normal range for Head Impulse Test values may vary slightly depending on the specific protocol used by the healthcare provider.

However, in general, a normal result indicates that the VOR is functioning correctly, and the eyes can maintain focus during head movements.

Below is a table showing the ranges of Head Impulse Test values and their meanings:

Head Impulse Test Value

Interpretation

Normal

VOR function is intact

High

Hyperactive VOR reflex

Low

Hypoactive VOR reflex

Absent

Absence of VOR reflex

What Do High Head Impulse Test Levels Indicate?

High Head Impulse Test levels, indicating a hyperactive VOR reflex, may be associated with conditions such as vestibular migraine, labyrinthitis, or superior canal dehiscence syndrome.

  • Possible causes of high Head Impulse Test levels include:
  • Inner ear infections
  • Inflammation of the vestibular nerve
  • Structural abnormalities in the inner ear

Risks associated with high Head Impulse Test levels may include increased sensitivity to head movements, vertigo, and difficulty maintaining balance during activities.

If you have high Head Impulse Test levels, your healthcare provider may recommend further evaluation to identify the underlying cause and develop an appropriate treatment plan.

What Do Low Head Impulse Test Levels Indicate?

Low Head Impulse Test levels, indicating a hypoactive VOR reflex, may be indicative of conditions such as vestibular hypofunction, bilateral vestibular loss, or acoustic neuroma.

  • Possible reasons for low Head Impulse Test levels include:
  • Damage to the vestibular organs
  • Degenerative conditions affecting the inner ear
  • Side effects of certain medications

Conditions associated with low Head Impulse Test levels may result in symptoms such as imbalance, unsteadiness, and visual disturbances during head movements.

If you have low Head Impulse Test levels, your healthcare provider may recommend vestibular rehabilitation therapy to improve balance and coordination, or further diagnostic tests to determine the underlying cause of your symptoms.

In conclusion, the Head Impulse Test is a valuable diagnostic tool for evaluating vestibular function and assessing the integrity of the VOR.

By understanding the purpose, costs, normal range, and implications of Head Impulse Test results, individuals can work with their healthcare providers to address vestibular issues and improve balance and coordination.

If you experience symptoms such as vertigo, dizziness, or imbalance, consider discussing the possibility of a Head Impulse Test with your healthcare provider to determine the best course of action for your vestibular health.