Ask your average layman about the complications of thyroid disease and chances are that they won’t realize it can affect the eyes. Indeed, thyroid diseases are frequently misunderstood and a pervasive poor understanding of the condition exists in many countries. It is usually most associated with weight gain problems.
However, thyroid disease has many possible complications far beyond the neck, the location of the thyroid gland. Of particular note to ophthalmology is thyroid eye disease (TED), a condition which is beginning to generate the attention it deserves. You may have heard of the condition via it’s other names of Graves’ orbitopathy or ophthalmopathy.
At its core modus operandi, TED causes the eye muscles, eyelids, tear glands and fatty tissues behind the eye to become inflamed. This usually causes the eyes and eyelids to become red, swollen and uncomfortable, pushing them forward to make them appear bulged. In some cases the swelling and stiffness becomes so severe that they can no longer move in sync, causing double vision.
The symptoms of TED usually begin to manifest with the aforementioned bulging eyes, combined with a feeling of grittiness. The eyes become watery, sensitive to light, swollen and red. Bags will begin to appear under the bulged eyes, pain will become more severe and the eyes will become difficult to move, causing the aforementioned double vision.
TED is an autoimmune condition which often occurs in conjunction with Graves’ disease. Indeed, in most patients, the same autoimmune condition that causes TED also affects the thyroid gland, resulting in Graves’ disease. TED can also occur in patients who suffer from overactive and underactive thyroids, and in some cases, with normal thyroids.
Lifestyle Risk Factors and Surprising Epidemiology
TED is a particularly important condition in the developing world and in countries like India. Dr. Sneha Thapliyal from the Vision Multispeciality Hospital in Kudal, Maharashtra, India, recently published a highly informative video lecture on TED.1 In her video, Dr. Thapliyal examined TED in great detail and highlighted the condition’s risk factors.
She reported that ophthalmologists should look for patients with a history of smoking, who are the most likely category of patients to develop TED. Hypothyroidism is also a major risk factor, particular in those with uncontrolled hyperthyroidism following radioactive iodine. Other common risk factors include age over 50, diabetes, high cholesterol levels and stress.
Dr. Thapliyal’s lecture is well worth watching if you are interested in TED, as a clinician, patient or for any other reason. It covers a number of various aspects of the disease from the aforementioned risk factors to diagnosis, treatment and other areas. Of particular note are the sections Dr. Thapliyal devotes to epidemiology and TED surgery.
There is a considerable discrepancy between men and women, as 16 women per 100,000 suffer from TED per year, whereas only 3 men per 100,000 have the condition. Given lifestyle factors are a risk factor this would seem to buck an international trend, where lifestyle choices are more likely to affect men. Severe cases are also more common among women than men.
The other standout of Dr. Thapliyal’s presentation were the various segments covering TED surgery, which are likely to be highly enlightening for ophthalmologists. In particular, the sections on techniques including orbital decompression, strabismus surgery and eyelid repair.
TED treatment is undergoing considerable change as novel therapies emerge to treat the condition. In particular, in 2019 a group of researchers based in California and mainland China examined novel treatment ideas.2 They noted that TED and its course were discovered over 60 years ago, but little development in treating the condition has subsequently taken place.
Teprotumumab: A New Frontier in TED Treatment?
Pointing to improvements in understanding TED’s molecular biology, the researchers reported that in randomized placebo-controlled trials, teprotumumab rapidly achieved improvement in clinical endpoints defining TED, including improved proptosis and diplopia. They also reported that dramatic improvement in clinical outcomes achieved after teprotumumab therapy during active TED are singular and comparable only to surgical therapies achieved during the inactive phase of TED.
Their success was corroborated by another study which was published in May of this year. Early Experience with Teprotumumab for Chronic Thyroid Eye Disease was carried out by a group of researchers also based in California, primarily in San Diego, who studied a 50-year-old female with a 3-year history of Graves’ disease, who presented with bilateral exophthalmos (greatest on the left side). She was followed for 2 years with stable proptosis measurements (23 mm OD, 28 mm OS).3
They concluded that teprotumumab may be used in patients with chronic TED and a low clinical activity score. Improvement in the proptosis and reduction in extraocular muscle volume suggest that teprotumumab may alter disease course, even in patients with inactive or quiescent TED. More research covering TED and various methods to treat the condition are reported to be in development.
References
- Thyroid Eye Disease. Available at https://www.youtube.com/watch?v=x_6Y-6IhrWI&feature=youtu.be. Accessed on September 9, 2020.
- Wang Y, Patel A, Douglas RS. Thyroid Eye Disease: How A Novel Therapy May Change The Treatment Paradigm. Therapeutics and Clinical Risk Management. 2019; 15: 1305–1318.
- Ozzello DJ, Kikkawa DO, Korn BS. Early Experience with Teprotumumab for Chronic Thyroid Eye Disease. The American Journal of Ophthalmology Case Reports. 2020; 19: 100744.
