Exophthalmus is a feature most commonly associated with which condition?

• A. Hypothyroidism
• B. Goiter
• C. Myxedema
• D. Graves disease

Answer: (D)

Exophthalmos is most commonly associated with Graves disease, an autoimmune hyperthyroid condition. In Graves, antibodies against the TSH receptor target not only the thyroid but also orbital tissues. These antibodies activate orbital fibroblasts, leading to inflammation, edema, and expansion of the extraocular muscles and retro-orbital connective tissue with glycosaminoglycan buildup. The enlarging tissue behind the eye pushes the globe forward, producing proptosis (exophthalmos) and sometimes diplopia. While hypothyroidism can cause myxedema (facial swelling) and goiter describes an enlarged thyroid, neither typically causes exophthalmos. Graves ophthalmopathy is the eye manifestation linked to this autoimmune process.