What is thyroid eye disease? Know symptoms and preventive measures
Thyroid eye disease usually affects people with over-active thyroid gland and may cause symptoms like dry eye, redness in eyes or sometimes blurry vision.
Thyroid eye disease (TED) is a rare autoimmune disease where eye muscles and fatty tissue behind the eye become inflamed. While it's mostly seen in patients with hyperthyroidism or over-active thyroid gland due to Graves’ disease, it can in very few cases also affect people who do not have thyroid disorder. While complete vision loss is extremely rare in this disorder, people suffering from thyroid eye disease may have blurred or double vision, dry or excessively watery eyes, red eyes or eye pain. People suffering from this eye disorder may feel colours do not appear as bright as before, when seeing from one or both eyes. One can manage the symptoms of the eye disease by quitting smoking, taking selenium supplements, and maintaining normal levels of thyroid hormones. (Also read: Thyroid Awareness Month: Common signs of thyroid in kids to watch out for)
What is thyroid eye disease
"Thyroid eye disease (TED) is a rare chronic immune mediated inflammation involving soft tissues, optic nerve, orbital vessels and extraocular muscles of the orbit. Seen in 25-50% of the patients with Graves’ disease, it is sometimes seen in euthyroid patients also. The systematic thyroid status unpredictably alters the cause of TED," says Dr Neeraj Sanduja, MBBS, MS, Ophthalmology.
Symptoms of thyroid eye disease
"The clinical Signs of TED most commonly are eyelid retraction, lagophthalmos or lid lag, altered contour of the upper eye lid (lateral flare), persistent dry eye with exposure keratopathy, corneal ulceration, perforation and endophthalmitis in very severe cases. Due to hypertrophy of soft tissues, there is raised intraocular pressure, proptosis or forward protrusion of the eye ball, venous congestion causing redness swelling and chemosis. Raised IOP can lead to a form of open angle glaucoma," says Dr Sanduja.
- Excessive watering
- Ocular pain and discomfort
- In extreme cases patient may also complain of blurring of vision and double vision. It can be unilateral or bilateral.
Dr Sanduja says due to inflammatory changes involving the orbital muscles, the person suffering from the condition may develop a squint or restriction of eye movements, diplopia or loss of binocularity.
"When the disease involves the optic nerve there is blurring of vision, altered colour vision, diminished contrast sensitivity and constriction of visual fields," he says.
Stages of TED
"Typically, there are three stages of TED - an initial phase when there is a steep rise in disease severity lasting 6 months to 5 years, the inflammatory phase or active disease and finally the stable inactive phase. However, the disease never returns to baseline and residual changes persist," says Dr Sanduja.
Some preventive measures which can be taken to decrease the chances and severity of disease and its sequalae are:
- Cessation of smoking
- Early detection of any dysthyroid state and its prompt management
- Prompt restoration of enthyroid state
- Aggressive immune suppressive therapy to prevent sequalae.