Facial Paralysis

The diagnosis of facial paralysis is often complicated. Facial paralysis may result from a disruption in the part of the brain called the motor cortex, injury to the facial nerve or damage to the muscles that control facial expression.

Diagnosis involves a consultation with a doctor, a complete physical exam and imaging studies of the brain and face. Your doctor may recommend one or more of the following imaging tests:


Complications affecting the eye are the most important concerns. The eye is constantly exposed to dry air and must be kept moist. Facial paralysis usually doesn't affect tear production, but it can affect the way the tears are distributed over the eye. There are many ways to prevent the drying effect, including taping, ointments, moisture chambers, patches, and even temporary suture-closure of the eyelid.

Potential conditions that are examined before undergoing treatment include:

  • Bell's phenomenon, a condition that causes an upward and outward movement of the eye
  • Corneal anesthesia, which causes a lack of sensation
  • History of dry eye syndrome

To assess the facial nerves affecting the eyes, electromyography (EMG) may be performed

UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.