Diagnosis

Bell's Palsy

Etiology

Cause

• Idiopathic

• Cold exposure (chilly wind, cold air conditioning, or driving with the car window down)

• Herpes simplex virus

• Traumatic

• Neoplastic

• Congenital

• Autoimmune

Pathophysiology [stg]

• A theory: unknown trigger --> edema and ischemia --> compression of the facial nerve within its bony canal

Risk factors [ud3]

• Diabetes

• Pregnancy

• Preeclampsia

• Obesity

• Hypertension

Complications [stg]

• Keratopathy

• Decreased quality of life

Epidemiology

Incidence per 100.000 [wei][vvc]

Approach

• Blood test

• Lyme disease testing

• CT caput

• MR caput

• Electromyography (EMG)

Treatment

1. Resolves completely without treatment in 80% of cases [stg]

2. Corticosteroids: Prednisone 1 mg/kg daily up to 60 mg for 5 to 7 days [stg]

3. Antivirals [i7m]

4. Prevent or treat treat exposure keratopathy: Eye lubrication and eye patch

5. Botulinum toxin: to alleviate spasms

6. Physiotherapy:

   • neuromuscular reeducation, surface EMG biofeedback, mime therapy, video self-modeling, massage, stretching, and relaxation

7. Surgery

   • Myomectomy (platysma): longer-term solution compared to botulinum toxin

   • Improving eye closure

   • Decompression of the facial nerve

   • Nerve transfer

   • Muscle transfer

Differential diagnoses

Acoustic neuroma, Benign tumors of salivary glands, Brain tumor, COVID-19, Cytomegalovirus, Guillain-Barre syndrome, Herpes zoster, HIV, Lyme disease, Malignant tumors of salivary glands, Melkersson-Rosenthal syndrome, Mononucleosis, Multiple sclerosis, Otitis externa, Parotitis, Sarcoidosis, Sjogren syndrome, Stroke, Temporal bone fracture, Trauma, Tuberculosis, Vasculitis