Abstract
POLGON (polarized light goniometer) was used to evaluate relative angular changes of shoulders while stepping in patients with unilateral acoustic neurinoma.
The mean angular change of shoulders (M. A. C. S.) and its coefficient of variation (C.V.) were selected as parameters of stepping.
1. M. A. C. S. was larger on the affected than on the intact side in patients with those with small tumors (1.0 to 1.9 cm).
2. In those with advanced tumors, both M. A. C. S. were increased.
3. In those with tumors large enough to exert pressure on the midbrain, M. A. C. S. was increased on the affected side.
4. The C. V. was influenced by vision.
These results suggest that POLGON is useful for determining the stage of acoustic neurinoma from the viewpoint of disequilibrium.
