Ptosis is an important side effect of frown correction by botulinum toxin type A (BTX-A). The most likely reason of eyelid ptosis is the diffusion of the toxin to levator palpebrae superioris muscle through orbital septum while the toxin is injected into the corrugator muscle.Objectives
In this pilot study, to prevent ptosis, we evaluated the efficacy of BTX-A injection at superior middle aspect of the corrugator muscle instead of the common injection site located above the medial eyebrow head.Methods
Fifteen patients were selected from those referred to our clinic with history of eyelid ptosis due to previous BTX-A (dysport; Ipsen) injection. They received three injections of BTX-A; 10 U into the procerus muscle and 20 U into the superior middle aspect of each corrugator muscle, instead of injecting into the belly of the corrugator muscles.Results
We observed excellent, good and moderate responses in 66.66%, 13.33% and 20% of our patients 2 weeks post-injection respectively. The outcomes were improved to excellent in the latter two groups by injecting 5 U of BTX-A (dysport; Ipsen) into the contractible corrugator in patients with good and 5 U in each corrugator (total of 10 U) in patients with moderate responses.Conclusion
Employing this method a very satisfactory outcome was obtained while no ptosis was observed. Therefore, we recommend this safe technique for treating patients with a history of eyelid ptosis.