Dynamic echography of extraocular muscles

The role of dynamic echography in the study of the optic nerve is well established and thanks to this technique it is easy to differentiate solid and fluid lesions. The study of the extraocular muscles, on the contrary, has been mainly static thus far. The problem is that it is difficult to evaluate the absolute thickness of a muscle because despite numerous percentile tables, muscle thickness is affected by various factors (sex, age, weight, height, occupation, etc.). We have measured the thickness of the muscle in the primary position, in contraction and relaxation, and have evaluated the differences in normal subjects and in various kinds of disorders that affect muscles (Graves' disease, myasthenia, abducens paralysis, atrophy, strabismus, etc.).