Steven C. Dresner, M.D.
Cosmetic Eye Surgery,
Blepharoplasty
June 2000 Ophthalmic Management
of Facial Nerve Paralysis by Steven C. Dresner, M.D. Illustrations by Christine Gralapp Introduction Patients with facial nerve paralysis may present to the ophthalmologist primarily with symptoms of corneal exposure related to poor eyelid closure, or may be referred by a colleague for the management of these symptoms. An understanding of the anatomy of the facial nerve and the etiology of the facial nerve paralysis is essential in managing the patient's symptoms with medical treatment or surgical rehabilitation. Anatomy The facial nerve, cranial nerve VII, is divided into four anatomic segments: supranuclear, nuclear, fascicular, and peripheral nerve. The supranuclear neurons that innervate the facial nerve nucleus lie in the precentral gyrus of the frontal lobe (see Figure 1).
Figure 1. Topographic anatomy of the facial nerve.
Discharges from the motor face area are carried through fascicles of the corticobulbar tract to the internal capsule, descending through the upper mid-brain to the lower brain stem, where they synapse in the facial nerve nucleus located in the pons. The corticobulbar tracts for the upper face cross and recross in reaching the facial nerve nucleus. The tracts for the lower face are crossed only (see Figure 2a). | |
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