Diplopia, commonly known as double vision, is a condition in which a person perceives two distinct images of the same object. This anomaly can be particularly confusing and uncomfortable and has a variety of causes. One of these, although fairly specific, is Graves' disease, an autoimmune condition that affects the thyroid gland.
What is Graves' disease?
Graves' disease is an autoimmune disorder in which the immune system mistakenly attacks the thyroid gland, causing it to produce excess thyroid hormones. This dysregulation leads to hyperthyroidism, with symptoms such as:
- Unexplained weight loss,
- Nervousness or irritability,
- Heart palpitations,
- Heat intolerance,
- Prominent or swollen eyes are a characteristic symptom known as Graves' ophthalmopathy.
It is this last point that links Graves' disease to diplopia.
Graves' disease occurs when the immune system attacks the tissues and muscles around the eyes. This leads to inflammation and swelling, which can affect the position and mobility of the eyeballs.
The eye muscles become stiff or dysfunctional, preventing the eyes from aligning correctly for binocular vision. As a result, the brain receives two different images instead of one, causing double vision.
Specific symptoms
Graves' disease diplopia is often intermittent initially, for example, when a person looks in a specific direction. Over time, it may become constant if the inflammation is left untreated. Other associated ocular signs include:
- Dry eyes,
- A feeling of pressure or pain behind the eyes,
- Photophobia (sensitivity to light),
- Ocular protrusion (exophthalmos), which can aggravate visual symptoms.
How is diplopia diagnosed and treated in this context?
Diagnosis is based on a thorough clinical evaluation, including:
- A complete visual examination with your optometrist,
- Imaging tests (MRI) to evaluate the orbital muscles,
- Blood tests to check thyroid hormone levels and detect antibodies specific to Graves' disease.
Treatment aims to manage both thyroid and ocular symptoms:
- Control of hyperthyroidism: Antithyroid drugs, radioactive iodine or surgery.
- Treatment of ocular inflammation.
- Surgical interventions: In severe cases, orbital decompression or eye muscle surgery may be required.
- Optical prisms: Integrated into glasses to temporarily correct double vision.
Graves' disease diplopia is an unpleasant but treatable complication. Early, multidisciplinary and appropriate treatment can relieve symptoms and prevent long-term complications. If you or someone you know suffers from diplopia or other symptoms associated with Graves' disease, don't hesitate to consult an Optometrist for an accurate diagnosis and appropriate treatment.
