Thyroid eye disease

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management

Definition

Thyroid eye disease (TED), also known as thyroid-associated orbitopathy, is an autoimmune condition causing inflammation and remodelling of the orbital tissues, typically associated with Graves' disease.

Aetiology

  • Autoimmune dysfunction: associated with hyperthyroidism (Graves' disease) but can also occur in euthyroid or hypothyroid patients.
  • Inflammatory infiltration: autoantibody-mediated attack on orbital fibroblasts and extraocular muscles.
  • Smoking: major risk factor for disease severity.

Pathophysiology

  • Thyroid-stimulating immunoglobulins (TSIs) target fibroblasts and extraocular muscles, leading to inflammation.
  • Fibroblast activation results in deposition of glycosaminoglycans and tissue expansion.
  • Increased orbital volume causes proptosis and compressive effects on the optic nerve.

Risk Factors

  • Graves' disease.
  • Smoking.
  • Female sex.
  • Radioiodine therapy (may exacerbate TED).
  • Genetic predisposition.

Signs and Symptoms

  • Proptosis: forward protrusion of the eyes.
  • Eyelid retraction: characteristic staring appearance.
  • Diplopia: due to extraocular muscle involvement.
  • Periorbital oedema: swelling around the eyes.
  • Optic neuropathy: vision loss in severe cases.

Investigations

  • Thyroid function tests: assess for hyperthyroidism or hypothyroidism.
  • TSH receptor antibodies: confirm autoimmune aetiology.
  • Orbital imaging (CT/MRI): evaluates extraocular muscle enlargement and optic nerve compression.

Management

1. Conservative Management:

  • Smoking cessation: crucial in reducing disease severity.
  • Lubricating eye drops: relieve dryness and irritation.
  • Sunglasses: protect from photophobia.

2. Medical Management:

  • Immunosuppressive therapy: corticosteroids for moderate to severe inflammation.
  • Biologic therapy: teprotumumab for refractory cases.

3. Surgical Management:

  • Orbital decompression surgery: for severe proptosis or optic nerve compression.
  • Strabismus surgery: for persistent diplopia.
  • Eyelid surgery: to correct eyelid retraction.

4. Referral:

  • Endocrinology: for thyroid disease optimisation.
  • Ophthalmology: for monitoring and management of TED complications.
  • Oculoplastic surgery: if surgical correction is required.
Eye DiseasesmypanotesThyroid eye disease