Bell's palsy vs Stroke
How to tell Bell's palsy and Stroke apart when a board question makes them look alike.
Step 2 CK pairs are in open beta while clinical review finishes. Spot an issue? Tell us.
Forehead movement, spared forehead suggests stroke while weak forehead indicates Bell's palsy.
Side by side
Acute unilateral lower motor neuron facial weakness including the forehead without limb deficits indicates Bell's palsy.
Facial droop with forehead sparing or additional focal neurologic deficits indicates central stroke until proven otherwise.
Inflammatory edema of the facial nerve in the facial canal causes peripheral CN VII dysfunction.
Focal cerebral ischemia or hemorrhage damages corticobulbar pathways, producing central facial weakness pattern.
Bell's palsy is a clinical diagnosis with complete ipsilateral forehead weakness, inability to close the eye, and normal brain imaging when obtained for atypical findings.
Stroke is supported by acute infarct or hemorrhage on neuroimaging and may show NIHSS elevation with additional cortical or motor deficits.
The trap
Learners label any facial droop as Bell's palsy and delay stroke workflow; forehead sparing, dysarthria, arm drift, or gaze findings should trigger immediate stroke protocol and head imaging.
The repair move
Next best step: activate stroke protocol, obtain emergent noncontrast head CT and glucose, assess last-known-well time, and if no bleed and within 4.5 hours evaluate alteplase eligibility; use Bell's palsy treatment with prednisone 60 mg daily for 5 days then taper only when deficits are isolated peripheral CN VII findings.
Try a free question
CoreA 58-year-old woman has abrupt left facial droop and difficulty speaking for 30 minutes. BP 166/92 mm Hg, HR 88/min, temp 37.0 C. Exam shows left mouth droop, left arm weakness, and preserved left forehead wrinkling. What is the next best step in management?
Show answer and explanation
Answer: B. Urgent stroke evaluation with immediate brain imaging. Forehead sparing plus arm weakness indicates central stroke and mandates emergent stroke workup.
Why the other choices are tempting
- A. Wrong because this is not isolated peripheral CN VII palsy.
- C. Wrong because EMG is not part of emergent management of possible acute stroke.
- D. Wrong because antivirals alone do not treat acute cerebrovascular ischemia.
- E. Wrong because observation risks missing reperfusion windows.
Flashcards
Tap a card to flip it.
Which facial exam feature most rapidly separates Bell's palsy from a central stroke pattern?
Forehead involvement separates them: Bell's palsy weakens the whole hemiface including forehead, while central stroke usually spares the forehead.
What associated neurologic finding strongly argues against Bell's palsy?
Any additional focal deficit such as arm weakness, aphasia, neglect, or visual field loss argues for stroke.
Quick answers
What is the fastest way to tell Bell's palsy from Stroke?
Forehead movement, spared forehead suggests stroke while weak forehead indicates Bell's palsy.
What is the key clue for Bell's palsy?
Acute unilateral lower motor neuron facial weakness including the forehead without limb deficits indicates Bell's palsy.
What is the key clue for Stroke?
Facial droop with forehead sparing or additional focal neurologic deficits indicates central stroke until proven otherwise.
What is the common trap with Bell's palsy vs Stroke?
Learners label any facial droop as Bell's palsy and delay stroke workflow; forehead sparing, dysarthria, arm drift, or gaze findings should trigger immediate stroke protocol and head imaging.