Suppression Head Impulse Test (SHIMP) versus Head Impulse Test (HIMP) When Diagnosing Bilateral Vestibulopathy

Area of Science:

• Vestibular Neuroscience
• Ophthalmology
• Neurology

Background:

• The Head Impulse Paradigm (HIMP) is challenged by covert saccades affecting Vestibulo-Ocular Reflex (VOR) gain calculation.
• The Suppression Head Impulse (SHIMP) test was developed to mitigate these challenges.

Purpose of the Study:

• To compare the efficacy of SHIMP versus HIMP in reducing covert saccades in Bilirubin Encephalopathy (BV) patients.
• To assess the diagnostic agreement between SHIMP and HIMP for BV.

Main Methods:

• A comparative study involving 98 BV patients.
• Quantification and comparison of covert saccades and VOR gain between SHIMP and HIMP.
• Evaluation of diagnostic agreement for BV (defined as horizontal VOR gain <0.6).

Main Results:

• SHIMP demonstrated a significant reduction in covert saccades compared to HIMP (p < 0.001).
• A statistically significant lower VOR gain was observed during SHIMP testing.
• Despite statistical significance, the clinical relevance of these differences was minimal.

Conclusions:

• SHIMP effectively reduces covert saccades in BV patients compared to HIMP.
• Both SHIMP and HIMP exhibit high agreement (93%) in diagnosing BV.
• SHIMP is a valuable alternative for assessing VOR gain in BV patients, offering improved saccade suppression.