BELL'S PALSY

ANATOMY

The nerve that is injured with Bell's Palsy is CN-VII (7th cranial nerve). It originates in an area of the brain stem known as the Pons. The 7th nerve passes through the stylomastoid foramen and enters the parotid gland. It divides into its main branches inside the parotid gland. These branches then further divide into 7000 smaller nerve fibers that reach into the face, neck, salivary glands and the outer ear. The nerve controls the muscles of the neck, the forehead and facial expressions, as well as perceived sound volume. It also stimulates secretions of the lower jaw, the tear glands and the salivary glands in the front of the mouth. Taste sensations at the front 2/3 of the tongue and sensations at the outer ear are transmitted by the 7th nerve.

PATHOPHYSIOLOGY

Post infectious demyelination (loss of fatty covering of the nerve coverings called 

called myelin sheath) of the facial nerve due to a prior upper respiratory infection

( INFLUENZA )

   

Inflammation within a small bony tube called the fallopian canal

   

Pressure is produced on the nerve resulting to its compression

within its bony canal

   

Inability of the damaged nerve to exit the skull and

divide into its several branches

   

Impairment of ALL functions controlled by the 7th cranial nerve

   

Interruption in the transmission of messages

the brain sends to the facial muscles

   

Idiopathic Facial Paralysis or

BELL'S PALSY

   

Facial weakness or Paralysis is to one or both sides;

drooping of the eyelid and corner of the mouth; drooling; dryness of the

eye or mouth; impairment of taste; excessive tearing in one eye;

speech difficulties and inabilityto eat on the affected area due to the relaxation of facial muscles