OHCM - Bell's Palsy Flashcards Preview

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Flashcards in OHCM - Bell's Palsy Deck (37):
1

Bell's palsy - Features distinguishing it from other causes are ...?

1. Abrupt onset (overnight or after a nap) with complete unilateral facial weakness at 24-72h.
2. Ipsilateral numbness or pain around the ear.
3. Decr. taste (ageusia).
4. Hypersensitivity to sounds (ie hyperacusis from stapedius palsy).

2

Bell's palsy - Other pathologies may be indicated by ...?

1. Bilateral symptoms.
2. UMN signs.
3. Other cranial neuropathies (eg V or XII, but also seen in 8% of idiopathic cases!).
4. Limb weakness.
5. Rashes.

3

Common causes of bilateral facial weakness:

1. Lyme.
2. Guillain-Barre.
3. Leukemia.
4. Sarcoidosis.
5. EBV.
6. Trauma.
7. Myasthenia gravis.

4

Bell's palsy - Incidence:

15-40/100.000/yr (1 patient/2yr/GP).

5

Female:Male =...?

1

6

Increased risk?

3x in pregnancy.
5x in diabetes.

7

Other symptoms of VII palsy (from any cause):

1. Unilateral sagging of the mouth, which is drawn upwards on the normal side on smiling, causing a grimace.
2. Drooling of saliva.
3. Food trapped between gum and cheek.
4. Speech difficulty.
5. Failure of eye closure may cause a watery or dry eye.
6. Ectropion (sagging and turning-out of the lower lid).
7. Injury from foreign bodies.
8. Conjunctivitis.

8

Signs:

1. Ask him to wrinkle his forehead and close his eyes forcefully (under bilateral cortical control so spared in UMN lesion).
2. Whistling/blowing out the cheeks tests buccinator (buccina = trumpet in Latin).

9

VII palsy - Etiology - General:

1. Bell's palsy (70%).
2. Ramsey Hunt syndrome.
3. Lyme disease.
4. Meningitis (eg fungal).
5. TB.
6. Viruses (HIV, polio).
7. Mycoplasma (rare).

10

VII palsy - Etiology - Brainstem lesions:

1. Stroke.
2. Tumor.
3. MS.

11

VII palsy - Cerebello-pontine angle:

1. Acoustic neuroma.
2. Meningioma.

12

VII palsy - Etiology - Systemic disease:

1. DM.
2. Sarcoidosis.
3. Guillain-Barre (often bilateral).

13

VII palsy - Etiology - ENT and other causes:

1. Orofacial granulomatosis.
2. Parotid tumors.
3. Otitis media or cholesteatoma.
4. Trauma to skull base.
5. Diving (barotrauma + temporal bone pneumocele).
6. Intracranial HYPOTENSION.

14

Tests - Blood:

1. ESR, glucose.
2. UP Borrelia antibodies in Lyme disease (indistinguishable clinically from Bell's).
3. UP VZV antibodies in Ramsay Hunt syndrome.

15

Tests - MRI:

1. SOLs.
2. Stroke.
2. MS.

16

Tests - CSF:

Rarely done - For infections.

17

Tests - Nerve conduction tests:

At 2 wks predict slow recovery by showing axon degeneration but don't influence treatment, so not routinely done.

18

Tests - Nerve conduction tests:

At 2wks predict slow recovery by showing axon degeneration but don't influence treatment, so not routinely done.

19

Prognosis - Incomplete paralysis:

Without axonal degeneration usually recovers completely within a FEW WEEKS.

20

Prognosis - Complete paralysis:

80% --> Full spontaneous recovery.
15% --> Have axonal degeneration (50% in pregnancy) - Delayed recovery, starting after 3 months + may be complicated by aberrant reconnections.

21

Aberrant reconnections?

1. Synkinesis: Eye blinking causes synchronous upturning of the mouth.
2. Misconnection of PNS fibers --> Crocodile tears (gusto-lacrimal reflex) - When eating stimulates unilateral lacrimation, not salivation (intra-lacrimal gland botox may help).

22

Management - Within 72h of onset:

1. Prednisolone (eg 60mg/d PO for 5d, tailing by 10mg/d) speeds recovery - 95% make full recovery.
2. Perhaps by reducing axonal edema, and thus damage.

23

Management - Antivirals:

Don't help, although some "Bell's cases" are thought to be associated with HSV-1, no-one has shown actively replicating virus.

24

Management - After 72h?

Little data to guide treatment if presenting after 72h of onset, but corticosteroids are widely used (remember: high doses can cause psychosis and hyperglycemia).

25

Management - In pregnancy?

No advice on the use of steroids is universally agreed in pregnancy.

26

Management - Protect the eye:

1. Dark glasses and artificial tears (eg hypromellose) if evidence of drying.
2. Encourage regular eyelid closure by pulling down the lid by hand.
3. Use tape to close the eyes at night.

27

Management - Surgery:

1. If eye closure remains a long-term problem (lagophthalmos), a lid loading procedure (eg with gold) to the upper lid may help.
2. If ectropion is severe --> Lateral tarsorrhaphy (partial lid-to-lid suturing) can help.
3. If no recovery in 1 YEAR --> Plastic surgery to help lid closure and to straighten the drooping face can be tried.

28

3 rare VII eponyms:

1. Ramsay Hunt syndrome.
2. Foville's syndrome.
3. Millard-Gubler syndrome.

29

Ramsay Hunt syndrome:

Described by James Ramsay Hunt in 1907 - Occurs when latent VZV reactivates in the geniculate ganglion of the VII nerve.

30

Ramsay Hunt syndrome - Symptoms:

1. Painful vesicular rash on the auditory canal: Herpes zoster oticus +/- on drum, pinna, tongue palate, or iris (--> hyphema, ie blood under the cornea).
2. Ipsilateral facial palsy.
3. Loss of taste.
4. Tinnitus/vertigo.
5. Deafness.
6. Dry mouth and eyes.

31

Ramsay Hunt syndrome - Incidence:

5/100.000 (higher if >60yr).

32

Ramsay Hunt syndrome - Diagnosis:

Clinical, as antiviral treatment is thought to be most effective within the 1st 72h, while the virus is replicating.

33

Ramsay Hunt syndrome - Treatment:

Antivirals (acyclovir 800mg PO 5x daily for 7 days) + Prednisolone as for Bell's palsy (according to a small retrospective analysis).

34

Ramsay Hunt syndrome - Prognosis:

If treated within 72h, 75% recover well; if not:
1/3 --> good recovery.
1/3 --> reasonable recovery.
1/3 --> poor recovery.

35

Foville's syndrome:

Pontine lesion giving VII palsy.
1. Ipsilateral horizontal gaze palsy.
2. Contralateral hemiparesis.
3. Hemisensory loss.
4. Internuclear ophthalmoplegia.

36

Millard-Gubler syndrome:

Occlusion of basilar artery branches in the pons gives:
1. Lateral rectus palsy (VI).
2. Ipsilateral facial paralysis.
3. Contralateral hemiplegia.

37

Bell's palsy is partly a diagnosis of ...?

Exclusion - 30% of facial palsies have a defined cause.