Bell’s Palsy (Facial Palsy)

Palsy means paralysis.  Bellโ€™s Palsy (named after a Dr. Bell from the early 1800โ€™s) is when one side of the face becomes partially- or fully-paralyzed.  Itโ€™s due to a problem with the Facial Nerve, the 7th of our 12 Cranial Nerves which begin in the brain and control movement and/or sensation of the head and neck.

The term Bellโ€™s Palsy is well-known, but it technically means that we donโ€™t know why it happens.  Yet nowadays, it seems that up to 70% of cases are due to Herpes simplex virus (HSV; see below).  So we more properly say โ€œFacialโ€ or โ€œ7th Nerveโ€ Palsy instead, although most people still call it โ€œBellโ€™sโ€.

Itโ€™s easy to identify a Facial Nerve Palsy on physical exam.ย  A patient:

  • canโ€™t raise their eyebrow well (or at all)
  • canโ€™t close their eye completely
    • we see the eyeball turn upward as they try to squeeze it shut
  • canโ€™t grimace / smile / frown well
  • has a droopy face

Facial Palsy is usually due to inflammation within a tiny opening in the bone right in front of the ear, where the nerve which has already exited the brain finally reaches the face.ย  Itโ€™s more common among persons with Diabetes, and pregnant women.ย  But before we ascribe it to HSV, we run through a number of other possibilities:

**  Herpes Zoster (Shingles)  —  Reactivation of the Varicella (chickenpox) virus, which has remained dormant in a nerve but awakens years later.  We suspect this if along with the palsy, thereโ€™s also ear or facial pain, ringing in the ear, or vertigo.

**  Lyme Disease  —  We suspect this in high-risk areas during high-risk seasons (see link).  Weโ€™d especially suspect Lyme in children with Facial Palsy, since they otherwise get the symptom so rarely.  In areas with lots of Lyme Disease, clinicians treat for it whenever a child has โ€œBellโ€™s Palsy.โ€

**  Acute (Primary) HIV  —  This refers to symptoms during the very first month after being infected with HIV.  Weโ€™d do various tests for the virus if a patient with Facial Palsy might have been at high risk, especially if they also have a fever, or have the palsy on both sides.  See the link.

**  Ear Tumors / Infections  —  Very rare causes.  Weโ€™d be able to feel something right at the opening to the ear canal, or see an infection looking inside.

**ย  Strokeย  —ย  As noted, Facial Palsy is from compression of the 7th Cranial Nerve after it has left the brain.ย  We tell patients, โ€œItโ€™s not a Stroke.โ€ย  But in rare cases, a stroke in the brain itself can be responsible, and thereโ€™s a way to tell.ย  When Stroke is the cause, the eyebrow isnโ€™t affected, only the lower face.ย  We have a patient raise their eyebrows, & we count the wrinkles on each side.ย  Fewer wrinkles on the affected side means eyebrow weakness, so no stroke.ย  See the pictures below.

Not a Stroke: entire half of face is weak (woman’s left side, man’s right side)……………………………………………………………………………………………

Stroke: able to raise both eyebrows fully, but lower left half of face weak when smiles

If none of the above conditions seem likely, we diagnose idiopathic Facial Palsy, i.e. โ€œBellโ€™s.โ€  Idiopathic is a fancy medical term for โ€œjust happens on its own, donโ€™t know why.โ€  But since the 1980โ€™s, weโ€™ve learned that 70% of cases seem due to Herpes simplex virus, Type-1 (HSV-1).  Thatโ€™s the type we get as children, and which causes cold sores / fever blisters on the lip; not the STD (type-2).  HSV-1 is transmitted to the mouth or nose by saliva (microscopic drops); initial symptoms (if any) disappear on their own, but the virus never goes away.  It remains latent (dormant) in a nerve, but can reactivate later in life.

Without treatment, 85% of patients with Facial Palsy begin to recover within 3 weeks, and achieve full or almost-complete recovery within 6 โ€“ 12 months.  Those with more severe weakness at the beginning may have some permanent weakness.  The most important part of treatment is high-dose steroid medication (e.g. prednisone) for 10 days; anti-Herpes medicine (at high doses, as given for Herpes Zoster) may also help, but isnโ€™t as important. 

Treatment should be begun as soon as possible.  Another important component is having the patient tape their eyelid shut, certainly during the night, and the day too if theyโ€™re willing.  Since the eyelid doesnโ€™t close completely, the cornea can be injured from dryness.  The patient should tape a small gauze pad over the lid, to maintain just the very tiniest bit of pressure (the purpose isnโ€™t to keep light out, but to keep the lid closed).

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