A 56-year-old female complained of diplopia immediately after surgical excision of a recurrent left skull base tuberculum meningioma. She was found to have a left sixth nerve palsy, which was subsequently treated with botulinum toxin injection to the medial rectus muscle. Three months post injection, the patient had partial recovery of the sixth nerve palsy and new-onset ocular neuromyotonia.
Keywords: Botulinum toxin; ocular neuromyotonia; sixth nerve palsy; skull base tumour.