What is the reoperation rate for strabismus surgery in patients with thyroid eye disease?

Short answer: Approximately 25%

I’d like to share a paper I’ve been working on recently that was just published by the American Journal of Ophthalmology!

I had the opportunity to observe numerous strabismus surgeries during my ophthalmology rotation this summer. This included several operations for patients with thyroid eye disease (aka Graves’ disease), one of which was a reoperation. Working with my mentor, Dr. Lambert, I developed a project using insurance databases to examine risk factors for reoperation after strabismus surgeries among patients with thyroid eye disease. I’d previously worked on some projects investigating the cost of various treatments for non-infectious uveitis using insurance databases, making this project much easier.

As some background, Graves’ disease is an autoimmune disease in which the body produces an antibody that overstimulates the thyroid. This can cause symptoms including swelling in the neck, diarrhea, heat intolerance, irregular heartbeat, fatigue, and insomnia. In a minority of patients, Graves’ disease also leads to scarring of the muscles of the eye and expansion of the tissue behind the eye (retro-orbital tissue). Scarring of the muscles of the eye leads to misalignment of the eyes (strabismus or squint) and double vision (diplopia). Expansion of the tissue behind the eyes can lead to the eyes bulging forward (proptosis). Famously, the actress Bette Davis was suspected to suffer from thyroid eye disease.

In some cases of strabismus that leads to double vision, surgery may be required. Some previous studies have examined the rate of strabismus surgery reoperation – however, our study is the largest reported in the literature thus far. More specifically, our study examined patients in a large commercial insurance claims database between 2003 and 2019 with thyroid eye disease who underwent at least one strabismus operation. We extract information about patient characteristics (age at diagnosis, sex, race), primary surgery characteristics (number of muscles operated on, which muscles were operated on, use of adjustable sutures), and timing of reoperations. We then used this information to examine associations between time to reoperation and patient/surgery characteristics.

The headline findings are that 111/448 patients in our study (24.8%) underwent a reoperation. The number of muscles operated on initially was the only independent predictor for undergoing a reoperation. Similarly, the number of muscles operated on initially was associated with a shorter time to the first reoperation. Other factors such as age at diagnosis of thyroid eye disease, the time between diagnosis of thyroid eye disease and surgery, gender, race, and other characteristics of the primary surgery were not associated with a time to reoperation.

Overall, I think our work contributes to the literature by providing an unbiased look at the rates of strabismus reoperation in thyroid eye disease. It also confirms that disease severity (which dictates the number of muscles operated on initially) likely drives the rate of reoperation. Finally, adjustable sutures did not reduce the rate of reoperations in patients with thyroid eye disease, which is consistent with previous work. Hopefully, this work will help with patient education and surgical decision-making!

I wish I could discuss the paper in more detail, but it’s still an “Article in Press” and only the abstract is available for non-subscribers to the American Journal of Opthalmology. If you have institutional access and have an interest in strabismus surgery, I encourage you to check out the paper!

Bonus quiz:

1. For which movies did Bette Davis win Best Actress?
2. Who sang “Bette Davis Eyes” (1981)?
3. Which new treatment for thyroid eye disease was FDA approved in 2020?

References:

1. Hwang B, Heo H, Lambert S. Risk Factors for Reoperation after Strabismus Surgery among Patients with Thryoid Eye Disease. American Journal of Opthalmology. November 2021. https://doi.org/10.1016/j.ajo.2021.11.022
2. https://eyewiki.aao.org/Thyroid_Eye_Disease
3. https://www.smartvisionlabs.com/blog/bette-davis-eyes/#:~:text=Those%20’Bette%20Davis%20eyes’%20could,eyes%20which%20makes%20them%20swell.
4. https://www.reviewofoptometry.com/article/thyroid-eye-disease-in-your-exam-lane
5. https://aapos.org/glossary/strabismus-surgery
6. Zhang MS, Hutchinson AK, Drack AV, Cleveland J, Lambert SR. Improved ocular alignment with adjustable sutures in adults undergoing strabismus surgery. Ophthalmology. 2012;119(2):396-402. doi:10.1016/j.ophtha.2011.07.044

Quiz Answers

1. Dangerous (1935) and Jezebel (1938). A scene from Jezebel is pictured above.
2. Kim Carnes
3. Tepezza (teprotumumab-trbw). IT’s an IGF-1R antagonist.