[Computed tomography in endocrine orbitopathy: the effects of varying gantry tilt and patient positioning on the measurement of eye muscle thickness and the possibilities for correction].

Thickening of eye muscles in endocrine orbitopathy can be demonstrated particularly impressively in coronary computed tomograms. However, when measuring the height and width of rectus eye muscles manifesting pathologic changes, the measurement is increased by a deviation from the coronary section plane; this is due to different tilting of the gantry. This often leads to an incorrect stage classification and makes objective observation of the course (e.g., under therapy) impossible. By converting the measured values into the actual extent of the muscles by means of the cosine set, appreciable changes in the pattern and frequency of affection of the rectus eye muscles were found in 121 patients examined.