What is the Head Impulse Test?
The Head Impulse Test, also known as the head thrust test, is a clinical examination used for detecting vestibular hypofunction and assessing the function of the semicircular canals in the inner ear. It is a crucial diagnostic tool for identifying vestibular dysfunction, particularly in patients with dizziness, vertigo, or balance disorders.
This test is typically administered to patients experiencing unsteady gait, unexplained falls, or acute vestibular syndrome. The primary goal is to evaluate the patient's head and eye velocity responses to sudden head movement, providing insights into their vestibular function.
Advantages and limitations of the test
The test is simple and can be performed at the bedside without specialized equipment. Moreover, the examiner can instantly observe and interpret the patient's response, making it a great tool for screening. It also has high clinical value because of its moderate sensitivity (63%) and high specificity (93%).
However, the test primarily assesses high-frequency vestibular function and may not detect low-frequency abnormalities. The accuracy of the test can depend on the examiner's skill and experience. Additionally, high acceleration head rotations required during the test may pose a risk of injury or exacerbate existing neck issues.










