Radioactive Iodine Therapy for Progressive Malignant Exophthalmos

Eighteen euthyroid patients with progressive malignant exophthalmos, of whom 16 had been treated by other forms of therapy, were treated with large therapeutic doses of radioactive iodine in an effort to ablate their thyroid glands. In four of the patients no functioning thyroid tissue could be demonstrated; in the others thyroid tissue can still be demonstrated with 5 mc doses of 131I preceded by thyrotrophin. In all patients, marked improvement of the infiltrative changes of ophthalmopathy resulted. Proptosis improved but in none of them did it regress completely to normal. The doses of radioactive iodine required to destroy thyroid remnants were much larger than the doses employed in the treatment of hyperthyroidism. It is suggested that the thyroid gland plays an important part in the complex problem of progressive exophthalmos and the presence of LATS, although its precise role remains to be determined.