In order to evaluate the predictability of the results in the treatment of myopathy in cases with the clinical signs of muscle involvement, 177 extraocular muscles of 27 cases whose oedematous status was detected by MRI and who were given antiinflammatory treatment according to the data of this method, were studied. The nature of involvement was detected in respect with the signal intensity and thickness of each rectus muscle prior to the treatment and at the end of the sixth month following a three months' application of combined treatment of steroids and irradiation of 2000 rads. When the initial and final results were compared, the signal intensities of four involved recti showed significant decrease at the end of the treatment, as they were evaluated separately or together. Besides the thicknesses of these groups of involved recti which were evaluated separately showed significant decrease. The evaluation of the signal intensities by MRI is a way that enables noninvasive detection of the edema and prediction of the anti-inflammatory treatment's results of dysthyroid myopathy. Therefore a systematic follow up by MRI is recommended for the treatment choice in dysthyroid myopathy.