Facial nerve exam and the House–Brackmann scale
- Examination
Testing the forehead, eyes and mouth tells a stroke from a facial nerve palsy; the House–Brackmann scale grades how weak the face is.
What it is
The facial nerve exam answers three questions: is the weakness central (brain) or peripheral (facial nerve), where along the nerve is the lesion, and how severe is it? The forehead is the key: it is spared in central lesions because the upper face has a bilateral cortical supply. Tears, taste and hyperacusis help locate a peripheral lesion. The ear, parotid and mouth are examined for a cause, and the House–Brackmann scale (grades I to VI) records severity and tracks recovery. Most acute peripheral palsies are idiopathic (Bell palsy), but only about half of all facial palsies are, so the exam looks for the others.
Findings and interpretation
- Peripheral lesion: forehead, eye closure and mouth are all weak on one side.
- Central lesion: the lower face is weak while forehead wrinkling and tight eye closure are largely preserved.
- A lesion proximal to the geniculate ganglion also reduces tears, saliva and taste and may cause hyperacusis.
- Weakness that progresses over weeks to months, or comes with other neurological signs, suggests a tumour or central cause: MRI.
- Bilateral facial palsy suggests Lyme disease or sarcoidosis rather than Bell palsy.
- After complete paralysis, about 90% recover fully if the nerve remains electrically excitable, and about 20% if it does not.
How it is done
- Inspect at rest: forehead lines, width of the palpebral fissure, nasolabial fold and corner of the mouth on each side.
- Ask the patient to raise the eyebrows: the key test for central versus peripheral weakness.
- Ask for tight eye closure, then try to open the eyes against resistance; note incomplete closure and the eye rolling upward.
- Ask the patient to show the teeth, puff out the cheeks and purse the lips; compare both sides.
- Grade the weakness with House–Brackmann (I to VI) and record it with the date and time of onset.
- Examine the auricle, ear canal and eardrum (vesicles, discharge, mass), the parotid gland and the mouth.
- When the site of the lesion matters, ask about taste, dry eye and sensitivity to loud sounds (hyperacusis).
- Complete a neurological exam: other cranial nerves, limbs, speech and gait.
House–Brackmann facial nerve grading
| Grade | Description | Eye closure |
|---|---|---|
| I | Normal facial function | Complete |
| II | Mild weakness seen only on close inspection | Complete |
| III | Obvious but not disfiguring asymmetry; synkinesis may be present | Complete with effort |
| IV | Obvious weakness or disfiguring asymmetry; normal tone at rest | Incomplete |
| V | Barely perceptible movement; asymmetry at rest | Incomplete |
| VI | Total paralysis, no movement | Incomplete |
Common mistakes
- Calling every facial palsy «Bell palsy»: only about half are idiopathic.
- Testing only the mouth: without the forehead test a stroke can be missed.
- Forgetting eye protection in a patient who cannot close the eye, which leads to corneal drying.
- Not looking in the ear, where otitis media, cholesteatoma or herpes zoster may be the cause.
Next step / Initial management
- Facial weakness with forehead sparing or any other stroke sign: emergency stroke pathway (call the emergency number).
- Idiopathic peripheral palsy: an oral corticosteroid started within 3 days, eye lubricants and taping the eye closed at night; herpes simplex antivirals alone give no benefit.
- Facial palsy with acute otitis media, cholesteatoma, trauma or ear vesicles: urgent same-day referral to ENT.
- Gradual onset, progression over weeks to months, other cranial nerve signs or bilateral palsy: priority referral for MRI and specialist workup.
Test yourself
Think of the answer, then tap the question to see it.
A patient cannot raise the right eyebrow, close the right eye or smile on the right. Central or peripheral lesion?
Peripheral (right facial nerve): the whole half of the face, including the forehead, is weak.
A 70-year-old has sudden right lower facial droop with normal forehead movement and a weak right arm. What is the concern?
Stroke (central lesion): forehead sparing plus limb weakness; emergency stroke pathway.
Where is the eye-closure dividing line on the House–Brackmann scale?
Grades I to III close the eye completely (III with effort); from grade IV eye closure is incomplete.
Which findings suggest a facial nerve lesion proximal to the geniculate ganglion?
Reduced tears and saliva, loss of taste and hyperacusis, in addition to facial weakness.
Connections
Educational content; it does not replace a medical assessment and is not a clinical instruction. For a real case, follow current guidelines and specialist advice.
Sources: Facial Nerve Palsy (MSD Manual Professional Edition, 2025); Signs and Symptoms of Stroke (Centers for Disease Control and Prevention, 2026); Acute Facial Palsy: Grading Severity (House–Brackmann) (RCEMLearning, Royal College of Emergency Medicine, 2026); Otitis Media (Acute) (MSD Manual Professional Edition, 2026).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.