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Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
Botulinum Neurotoxin for Postoperative Facial Nerve Paralysis: A Technical Note
Nitish Kamble1, Dhaval Shukla2, Dhananjay Bhat2
1Department of Neurology, National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru, Karnataka, India.
Neurology India
|July 21, 2026
Summary
Botulinum neurotoxin (BoNT) injections effectively prevent exposure keratitis in patients with postoperative lower motor neuron (LMN) facial nerve paralysis by inducing eyelid ptosis. This treatment offers a safe alternative to tarsorrhaphy with no observed complications.
Area of Science:
- Neurosurgery
- Ophthalmology
- Neurology
Background:
- Vestibular schwannoma excision can risk facial nerve injury, leading to lower motor neuron (LMN) facial nerve paralysis.
- Postoperative facial nerve paralysis can result in exposure keratitis due to incomplete eyelid closure.
- Tarsorrhaphy is a traditional method to protect the cornea but can be cosmetically undesirable.
Purpose of the Study:
- To evaluate the efficacy of botulinum neurotoxin (BoNT) injections in preventing exposure keratitis in patients with postoperative LMN facial nerve paralysis.
- To assess BoNT as an alternative to tarsorrhaphy for corneal protection.
Main Methods:
- Retrospective evaluation of 18 patients with postoperative LMN facial nerve paralysis.
- Patients received botulinum neurotoxin (BoNT) injections into the upper eyelid.
- Eyelid ptosis induction and development of exposure keratitis were monitored.
Main Results:
- Botulinum neurotoxin (BoNT) successfully induced ptosis in 14 out of 18 patients (78%).
- Partial ptosis occurred in ten patients, and complete ptosis in four.
- None of the patients who received BoNT injections developed exposure keratitis.
Conclusions:
- Botulinum neurotoxin (BoNT) is an effective and safe therapy for preventing exposure keratitis in patients with postoperative LMN facial nerve palsy.
- BoNT offers a viable alternative to tarsorrhaphy, with no immediate or late complications reported.
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