What are the key clinical features of Bell’s Palsy?

• Unilateral facial weakness (entire upper + lower face affected).

• Sudden onset (peaks within 72 hours).

• Associated symptoms:

  • Loss of forehead wrinkling.

  • Inability to close eye (risk of corneal drying).

  • Altered taste (chorda tympani involvement).

• Absence of:

  • Limb weakness, dysarthria, or other neurological deficits (rules out stroke).

  • Rash (rules out Ramsay Hunt syndrome).

Why this matters:

• Bell’s Palsy is idiopathic (post-viral inflammation of CN VII).

• Differentiating from stroke is critical (stroke spares forehead due to bilateral innervation).

How would you differentiate Bell’s Palsy from a stroke?

Why this matters:

• Stroke is time-sensitive (needs CT/MRI and thrombolysis if ischemic).

• Bell’s Palsy is managed conservatively (steroids + eye care).

What is the first-line treatment for Bell’s Palsy?

• Prednisolone 50mg OD for 10 days (start within 72 hours of onset).

• Eye care:

  • Artificial tears (daytime).

  • Lubricating ointment (nighttime).

  • Tape eye shut if unable to close (prevent corneal abrasion).

• Antivirals (e.g., acyclovir): Only if Ramsay Hunt suspected (rash + ear pain).

Why this matters:

• Steroids reduce inflammation and improve recovery time.

• No antivirals unless herpes zoster is confirmed (NICE guidelines).

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What red flags suggest an alternative diagnosis?

• Bilateral facial weakness (Guillain-Barré, Lyme disease).

• Rash in ear/face (Ramsay Hunt syndrome).

• Hearing loss/vertigo (acoustic neuroma).

• Limb weakness/dysarthria (stroke).

• Slow progression (tumour, sarcoidosis).

Why this matters:

• Bell’s Palsy is a diagnosis of exclusion – rule out stroke, infection, and malignancy.

   

How would you counsel a patient about prognosis?

• 70% recover fully within 6-9 months.

• 30% have residual weakness/synkinesis (abnormal muscle movements).

• Recurrence risk: 5-10%.

• Reassurance: "Most people regain normal facial function with treatment."

Why this matters:

• Addresses anxiety about permanent disfigurement.

When would you refer for imaging (MRI/CT)?

• Atypical features:

  • Bilateral weakness.

  • Slow progression.

  • Other cranial nerve involvement.

• Suspected stroke: Urgent CT head.

• No improvement after 3 months.

Why this matters:

• Most Bell’s Palsy cases do not need imaging.

What safety-netting advice would you give?

• Return if:

  • Eye becomes red/painful (corneal ulcer).

  • Symptoms worsen or spread.

  • New rash/ear pain (Ramsay Hunt).

• Follow-up: GP review if no improvement in 4 weeks.

Why this matters:

• Prevents complications (e.g., vision loss from corneal exposure).

Key OSCE/PLAB 2 Tips: