Clinical features, evaluation, and management of ophthalmic complications of facial paralysis: A review.

The purpose of this review was to study the evaluation, diagnosis, and management of ophthalmic complications associated with facial nerve palsy and to discuss the current and future interventions. The ophthalmic complications of facial paralysis include lagophthalmos, ectropion, exposure keratopathy, ocular synkinesis, and crocodile tears. Evaluation by an ophthalmologist skilled in recognizing and managing complications of facial paralysis shortly after its initial diagnosis can help identify and prevent long-term complications. Several types of grading scales are used to evaluate, measure the severity, and track surgical and patient-reported treatment outcomes. Lagophthalmos or ectropion are managed using temporary measures aimed at lubricating and covering the eye, including scleral lenses; however, these measures can be expensive and challenging to acquire and maintain. Temporary surgical interventions include lateral tarsorrhaphy, weighted eyelid implants, lateral canthoplasty, and other procedures that tighten or lift the eyelid or surrounding tissues. Management of flaccid facial paralysis due to iatrogenic injury or neoplasm requires neurorrhaphy or graft repair. The most common techniques for dynamic reconstruction in chronic facial paralysis are regional and free muscle flap transfer. Future directions for the management of ophthalmic complications aim to induce blinking and eye closure by developing systems that can detect blinking in the normal eye and transmit the signal to the paralyzed eye using mechanisms that would stimulate the muscles to induce eyelid closure. Blink detection technology has been developed, and a study demonstrated that blinking can be stimulated using electrodes on the zygomatic branch of the facial nerve. Further studies are needed to develop a system that will automate blinking and synchronize it with that of the normal eye.