Abstract
BACKGROUND: The ocular adverse reactions caused by the diffusion of BoNT-A injection are self-limiting, with symptoms ameliorating over time. Thyroid-associated ophthalmopathy (TAO) is an autoimmune disease characterized by symptoms such as exophthalmos, diplopia, and eyelid retraction, which may overlap the side effects of BoNT-A injections. It is crucial to consider other ocular diseases when assessing side effects after BoNT-A injection, particularly in patients with a history of thyroid disease. AIMS: To describe a complicated case of concurrent malignant exophthalmos and unilateral blepharoptosis following an additional dosage of BoNT-A injection for glabellar wrinkles. PATIENT: A 58-year-old female patient received BoNT-A injection for glabellar wrinkles. Two weeks later, the patient requested an additional dose of BoNT-A to enhance the effects, receiving an extra 8 units BoNT-A in the brow muscles. Twenty days later, she presented with a ptosis in the left eye, which progressively manifested into symptoms of exophthalmos, uncoordinated movement, blurred vision, and double vision. Ultimately, she was diagnosed with malignant exophthalmos. RESULTS: The blepharoptosis following BoNT-A injection typically manifests a significant improvement within 1-3 months. However, if the symptoms of ptosis persist without evident amelioration and are accompanied by additional ocular discomfort, particularly in patients with thyroid disease, the potential presence of concomitant TAO should be considered. CONCLUSIONS: This report highlights the potential relationship between botulinum toxin and thyroid disease, emphasizing the complexity of complications following cosmetic injections. Clinicians should carefully take the history of a patient, thereby facilitating better identification and management of potential complications.