Quantitative Assessment of Intention Tremor after Brain Injury Using Tri-axial Accelerometry

ABSTRACT

OBJECTIVE: The aims of this study were to assess intention tremor severity caused by brain injury using tri-axial accelerometry and also to determine the reliability and the correlation with clinical measurements. METHOD: Twenty two patients with intention tremor caused by brain injury were included. The quantitative measurement of tremor was performed using tri-axial accelerometry during finger to nose test. The dominant frequency and amplitude of tremor were acquired using Fast Fourier transformation analysis. The severity of tremor was also clinically rated by clinical rating scale for tremor, hand writing test, figure drawing test, pouring water test. The correlation between clinical measurement and tri-axial accelerometry measurement, and the inter-rater reliability were assessed. RESULTS: The tri-axial accelerometry measurement showed good inter-rater reliability. The mean dominant frequency was 3.10 Hz. The amplitudes at dominant frequency were significantly correlated with clinical rating scale for tremor, pouring water test (p<0.05) but not with hand writing test, figure drawing test. CONCLUSION: Quantitative measurement of intention tremor using tri-axial accelerometry may be very useful to assess the tremor severity caused by brain injury.