Pathological and clinical study of Müller's muscle in Graves' ophthalmopathy.

Specimens of Müller's muscle from patients with Graves' disease were examined for evidence of morphologic, histochemical, immunohistochemical and electron microscopic changes. No scarring, significant inflammation or shared antigenicity between Müller's muscle and thyroglobulin-related antigens was found. There were moderate numbers of mast cells in 48 of 66 specimens. Computed tomography in 16 patients with Graves' ophthalmopathy showed enlargement of the superior rectus-levator complex in 17 of 28 orbits with lid retraction. However, no correlation was found between the amount of lid retraction and the degree of enlargement of the muscle complex.