Treatment of Thyroid Eye Disease-Associated Ophthalmopathy and Myopathy With Intraorbital Injection of 5-Fluorouracil and Triamcinolone Acetonide

PURPOSE: The authors report a technique of local application of anti-metabolite and corticosteroid mixture in the orbit for treatment of thyroid orbitopathy with moderate-severe inflammation and muscle involvement. METHODS: Patients of one orbital surgeon seen between March 2019 and May 2020 with active thyroid eye disease and restrictive strabismus were considered for local treatment of the myopathic component of the disease. A mixture of 1 ml 5-FU 50 mg/ml, 0.25 ml triamcinolone 40 mg/ml, and 1 ml lidocaine 2% is injected through the skin using a 25-gauge, 1.5-inch needle into the orbit adjacent to the affected extraocular muscle. Six patients were treated in the outpatient setting and 3 patients have been treated with this intervention intraoperatively at the time of orbital decompression. One was treated with the mixture reconstituted with hyaluronic acid (Healon GV) to address postoperative medial rectus fibrosis to the medial wall, this mixture was applied topically in the operative field and not injected. RESULTS: All patients had subjective improvement in the eye movement limitation and 2 patients had a change in motility on exam that was temporally correlated to injections. One patient did not disclose high-dose aspirin intake before injection and experienced a retrobulbar hemorrhage immediately following injection which was successfully treated. No complications were noted as a result of the medication itself. DISCUSSION: The combination of 5-fluorouracil and triamcinolone acetonide for orbital treatment may be a useful adjunct in treating patients with ongoing inflammatory activity, both in the office and in the operating room. The novel combination may optimize ophthalmic outcomes, modifying disease course in some patients.