A case of botulinum toxin injections for the management of chronic 3rd and 4th nerve palsies

A 66-year-old female presented with exotropia and hypertropia of her left eye. She had a previous history of lateral rectus recession and medial rectus resection of her left eye 20 years prior to old oculomotor and trochlear nerve pareses. She was treated with a botulinum toxin injection in the inferior oblique and lateral rectus muscles of her affected eye. In this case, the patient’s exotropia and hypertropia of her affected eye were greatly reduced after injections. Botulinum toxin chemodenervation can be considered as a subsidiary treatment option to the ultimate surgery not only for acute paralytic strabismus but also for chronic paralytic strabismus and further study may be necessary.