Thyroid eye disease is a syndrome of clinical and orbital imaging abnormalities caused by deposition of mucopolysaccharides and infiltration with chronic inflammatory cells of the orbital tissues, particularly the extraocular muscles. It usually occurs in association with autoimmune hyperthyroidism. Clinical or laboratory evidence of thyroid dysfunction and thyroid antibodies may not be detectable at presentation or even on long-term follow-up, but their absence requires consideration of other disease entities. Radioiodine therapy, possibly indirectly due to induction of hypothyroidism, and cigarette smoking increase the severity of thyroid eye disease, and ethanol injection of thyroid nodules have been reported to be followed by severe disease (see Chapter 26-08). Ocular myasthenia and thyroid eye disease are associated and may coexist, the presence of ptosis rather than lid retraction being more characteristic of the former.
The primary clinical features are proptosis, lid retraction and lid lag, conjunctival chemosis and episcleral inflammation, and extraocular muscle dysfunction (Figure 7–5) (eFigure 7–69). Resulting symptoms are cosmetic abnormalities, surface irritation, which usually responds to artificial tears, and diplopia, which should be treated conservatively (eg, with prisms) in the active stages of the disease and only by surgery when the disease has been static for at least 6 months. The important complications are corneal exposure and optic nerve compression, both of which may lead to marked visual loss. The primary imaging features are enlargement of the extraocular muscles, usually affecting both orbits (eFigure 7–70). The clinical and imaging abnormalities of thyroid eye disease may be mimicked by dural carotico-cavernous sinus fistula.
Thyroid eye disease (Graves ophthalmopathy). Proptosis, lid retraction, and vertical and horizontal squint. (Used, with permission, from M R Vagefi.)
CT scan of thyroid eye disease (Graves ophthalmopathy). A: Axial section showing markedly enlarged medial recti and left lateral rectus (arrows) and distortion of right optic nerve (arrowhead). B: Coronal section showing optic nerves (arrowheads) and markedly enlarged medial recti and left inferior rectus (arrows).
Thyroid eye disease. Inferior rectus fibrosis causing (A) downward deviation and (B) limitation of elevation of right eye. (Reproduced, with permission, from Riordan-Eva P, Augsburger JJ. Vaughan & Asbury’s General Ophthalmology, 19th ed. McGraw-Hill, 2018.)
See Graves Ophthalmopathy, Chapter 26-08. Treatment options for optic nerve compression or severe corneal exposure are intravenous pulse methylprednisolone therapy (eg, 1 g daily for 3 days, repeated weekly or monthly for up to 3 months), oral prednisolone 80–100 mg/day, radiotherapy, or surgery (usually consisting of extensive removal of bone from the medial, inferior, and lateral walls of the orbit), either ...