[Figure, Botulinum Toxin Injections for Blepharospasm...] - StatPearls - NCBI Bookshelf

Botulinum Toxin Injections for Blepharospasm. Botulinum toxin injections may be administered at various sites, as depicted in the image. The dosage varies depending on the severity of the blepharospasm and apraxia of eyelid opening at each specific point. Pretarsal injections are administered to specifically counteract apraxia of eyelid opening. Injections just lateral to the lateral nasal wall aim to alleviate the squeezing of the nasalis muscle, which is observed in some patients. Injections into the corrugator and procerus muscles reduce the downward movement of the brow, consequently aiding eyelid control. Injections just below the brows provide a chemical lift to the brows, thereby improving the ability to open the eyelids. Caution is warranted to inject a minimal amount over the zygomaticus major and minor muscles to prevent the appearance of lower facial weakness following injections. Contributed by BCK Patel, MD, FRCS