Thyroid associated ophthalmopathy:: botulinum toxin A in the treatment of upper eyelid retraction -: a pilot study

Purpose: Eyelid retraction in patients with thyroid associated ophthalmopathy is a common cause of eye discomfort and a disfigured facial appearance. The aim of this pilot study was to evaluate the effects and safety of inducing a temporary partial ptosis of the eyelid through injection of botulinum toxin A into the levator palpebrae superioris muscle. Methods: Nine patients were treated. They were followed up with ophthalmologic examinations and self-assessment questionnaires until the point at which they either required renewed treatment or had no residual effect of the first injection. Maximum follow-up time was twenty weeks. Results: In all eyes but one there was a lowering off the eyelid position one week after treatment and all these patients reported ani improvement of eye appearance and symptoms. There was variability in the degree of lowering of the eyelid with the same dose of injected botulinum toxin A. It was also difficult to predict the time interval needed for re-treatment. Ptosis impairing visual acuity was not a consequence of the treatment in any of the patients. One week after treatment two patients experienced increased diplopia but only one showed transient change in Lees screen measurement of eye motility. Conclusion: Botulinum toxin A injection may be used to lower the upper eyelid position in patients awaiting eyelid surgery. The treatment safely relieved symptoms and improved eye appearance. However, treatment was short term and difficult to predict. There is also an inherent risk of transient diplopia.