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Facial nerve paralysis: the ENT approach

In peripheral facial palsy three questions are asked: is the palsy complete or partial, did it appear at once or gradually, and what is the cause (Bell, Ramsay Hunt, trauma, tumour or infection); complete palsy is assessed with electrical testing (ENoG) between day 3 and day 14, and the speed of recovery depends on the degree of nerve injury under Sunderland.

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Why it matters in the exam

The exam tests the distinction between central and peripheral (central spares the forehead), House-Brackmann grading from I (normal) to VI (complete palsy), and the reading of electrical tests. ENoG compares the response of the affected side with the healthy side: degeneration of 90% or more within 14 days of complete palsy predicts poor recovery, and in some centres justifies nerve decompression in Bell palsy or trauma. EMG after 14 days looks for voluntary potentials or signs of reinnervation. Electrical testing is not needed in partial palsy.

Under Sunderland: grade I — neurapraxia (conduction block without axonal damage), grade II — axonotmesis with intact endoneurium; in both, recovery can be complete. Grade III — endoneurial injury, partial recovery with synkinesis; IV — perineurial injury; V — complete transection of the nerve. Nerve segments: intracranial, meatal, labyrinthine (narrowest, at the meatal foramen — where compression arises in Bell palsy), tympanic, mastoid and extratemporal. Branches: the greater superficial petrosal nerve (tears), the nerve to stapedius and the chorda tympani (taste to the anterior two-thirds of the tongue).

Facial palsy that progresses gradually over weeks, recurrent palsy on the same side or palsy with a parotid lump are warning signs of a tumour and require imaging. Bilateral palsy raises suspicion of Lyme disease, Guillain-Barré, sarcoidosis or leukaemia. A nerve cut during surgery and recognised at once is repaired by direct suture or a nerve graft (great auricular or sural). After long-standing palsy: nerve transfer (hypoglossal or masseteric), cross-face nerve graft or free muscle transfer (gracilis); static measures such as an eyelid gold weight. In every palsy — protect the eye: artificial tears, ointment and night cover.

Key points

• Central spares the forehead; peripheral does not.
• House-Brackmann I to VI.
• ENoG between day 3 and day 14; degeneration 90% or more — poor prognosis.
• Sunderland I and II — full recovery possible.
• Gradual or with a lump — look for a tumour.

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Sources

• AAO-HNS Clinical Practice Guideline: Bell's Palsy, 2013 — Electrodiagnostic testing and surgical decompression
• Cummings Otolaryngology: Head and Neck Surgery, 7th edition (2021) — Clinical disorders of the facial nerve; facial nerve reanimation
• House JW, Brackmann DE. Facial nerve grading system, 1985 — Grading scale

Sources are given for further reading; the text is written afresh and not copied from them.

Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.