Bells Palsy & Trigeminal Neuralgia Flashcards
Bells Palsy
what is the most common etiology?
unilateral facial nerve palsy
Bells Palsy
epidemiology (age, gender, seasonality)
- usually adults, peak ages 20-40 y/o
- men and women equally affected
- rarely occurs in the summer
Bells Palsy
risk factors?
5
- DM
- immunocompromised
- pre-eclampsia
- recent URI
- recent pfizer vax
Bells Palsy
differentiate upper and lower motor neuron lesions
- UMN: lesions affecting the corticobulbar tract
- LMN: lesions affecting individual branches
Bells Palsy
pathophys
may affect any/all four fiber types carried by facial nerve
* somatomotor axons to facial muscle (presents as facial weakness)
* axons supplying stapedial muscle (hyperacusis)
* gustatory fiber insult (hypo or dys geusia)
* sensory fiber insult (otalgia and post-auricular pain, lacrimal/salivary gland dysfunction)
Bells Palsy
describe the HSV hypothesis
- cause causing primary infection on the lips (cold sores), the virus travels up sensory nerve axons and then reactivates and causes damage to myelin
Bells Palsy
may be secondary to?
- autoimmune reactions that cause facial nerves to demyelinate
Bells Palsy
within how long do sx evolve?
72 hours
Bells Palsy
presentation of illness
5 components
- unilateral facial palsy of acute onset
- ipsilateral post-auricular pain, mild to mod otalgia, hyperacusis, or phonophobia
- hypo or dysgeusia
- subjective tongue or facial hypoesthesia
Bells Palsy
PE Exam components which will be unremarkable
- focused neuro exam
- complete head/neck exam (CN exam, otoscopy, tuning fork exams)
Bells Palsy
what is Bell Phenomenon
L eye rolls upward and inward
Bells Palsy
which side of the face is usually affected?
R side of the face
Bells Palsy
sparing of the brow on PE indicates?
upper motor neuron lesion
Bells Palsy
essentials of dx
3 essentials +/- 2 others
- sudden onset of lower motor neuron facial palsy
- hyperacusis or impaired taste
- no other neurologic abnormalities
- post-auricular pain or trigeminal neuralgia
Bells Palsy
diagnosis to exclude
- facial palsy of known etiology or a palsy that is progressive, waxing, waning, or affects facial zones in an uneven fashion
IS NOT BELLS PALSY
Bells Palsy
what would uneven distribution of weakness indicate?
neoplasm
Bells Palsy
what if it was vesicular palsy?
zoster
Bells Palsy
diagnostics
3 components
- “if it looks like a horse, it’s probably a horse”
- imaging PRN to r/o stroke or neoplasm
- Lyme testing if indicated
Bells Palsy
differentials
8
- Herpes Zoster
- Lyme Disease
- Benign Facial Nerve Tumor
- Malignant Facial Nerve Tumor
- Delayed onset palsy from facial trauma
- chronic otitis media or cholesteotoma
- otitis externa
- CVA