What is the purpose of Bell’s phenomenon in assessing facial weakness?

What is the purpose of Bell’s phenomenon in assessing facial weakness?

Bell’s phenomenon is a useful test to determine whether a patient is genuinely trying to close their eyes. When the orbicularis oculi muscles contract forcefully (as in blinking), the eyes naturally roll upward unless there is paralysis of the extra-ocular muscles. This phenomenon helps assess the integrity of these muscles during facial weakness evaluations.

Verified by Dr. Petya Stefanova