Thyroid Eye Disease (Graves Ophthalmopathy)

Key Features

• 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

• Usually occurs in association with autoimmune hyperthyroidism

• Radioiodine therapy, possibly indirectly due to induction of hypothyroidism, and cigarette smoking increase its severity

• Ethanol injection of thyroid nodules has been reported to be followed by severe disease

• Ocular myasthenia and thyroid eye disease are associated and may coexist; presence of ptosis rather than eyelid retraction is characteristic of the former

Clinical Findings

• Primary clinical features

  • Proptosis

  • Lid retraction and lid lag

  • Conjunctival chemosis and episcleral inflammation

  • Extraocular muscle dysfunction

• Resulting symptoms

  • Cosmetic abnormalities

  • Surface irritation, which usually responds to artificial tears

  • Diplopia

• Important complications are corneal exposure and optic nerve compression, both of which may lead to marked visual loss

Diagnosis

• The primary imaging features are enlargement of the extraocular muscles, usually affecting both orbits

• Clinical or laboratory evidence of thyroid dysfunction and thyroid autoantibodies may not be detectable at presentation or even on long-term follow-up

• Clinical and imaging abnormalities of thyroid eye disease may be mimicked by dural carotico-cavernous fistula

Treatment

• Euthyroidism should be established and maintained in all cases

• Mild disease: Oral selenium seems to be beneficial

• Moderately severe disease: Treatment options when there is no visual loss is controversial

  • Peribulbar corticosteroid injections have been advocated

  • Surgical decompression may be justified in patients with marked proptosis

  • Lateral tarsorrhaphy may be used for moderately severe corneal exposure

• Severe disease: Treatment options for optic nerve compression or severe corneal exposure include

  • 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

  • Surgery (usually consisting of extensive removal of bone from the medial, inferior, and lateral walls of the orbit)

• Other procedures are particularly useful for correcting lid retraction but should not be undertaken until the orbital disease is quiescent and orbital decompression or extraocular muscle surgery has been undertaken

• Diplopia 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