VELOCITY ANALYSIS OF THE SWAY IN THE CENTER OF GRAVITY OF THE BODY
LATERAL SWAY VELOCITY IN PERIPHERAL VESTIBULAR DISORDERS
1986 Volume 89 Issue 6 Pages 754-762
Details
1986 Volume 89 Issue 6 Pages 754-762
The bodily sway may be quantitatively evaluated in detail when the data are subjected to a computer analysis. Such analyses are feasible for diverse aspects of the phenomenon of "bodily sway" including the distance, extent, direction, velocity, acceleration velocity, and power spectrum. Among these, our interest has been to investigate the change in velocity of laterally-directed bodily sway in vestibular disorders and its correlation with the direction and magnitude of nystagmus. When our velocity analysis method for 8 directions was employed, there was a close correlation between the velocity of lateral sway and the direction of nystagmus when the eyes were closed.
This report deals with velocity of the bodily sway and lateralized velocity, correlatively studied in patients with peripheral vestibular disorders.
In acute monophasic peripheral vestibular disorders, the velocity of lateral bodily sway and the difference in counter-directed velocity were both greater than the corresponding control value. However, even among patients with acute vestibulopathies, patients during the first attack and those during an episode of repeated attacks showed a different response; specifically, for those who were in an acute phase of repeated attacks, the bodily sway to the lateral directions was smaller while the nystagmus appeared to be the same in intensity. In bilaterally-involved vestibulopathies in which caloric response was moderately reduced, the velocity of lateral bodily sway and the
velocity difference were close to a normal value. Those patients who did not respond to 50ml of ice-cold water introduced into the each external meatus and were Romberg phenomenon positive, revealed a large lateral sway velocity, while the velocity difference was rather small both when the
eyes were opened and closed. Therefore, the postural controls may be maintained rather effectively even in those with bilateral vestibulopathy when the caloric response is only modestly or moderately impaired. These results indicate that the bodily sway as assessed by the velocity of lateral directions and the velocity difference should be interpreted in a different way.
