Changes in Facial Expression With Myasthenia Gravis

The autoimmune condition myasthenia gravis (MG) may cause changes in a person’s facial expressions. These changes are especially noticeable around the eyes and mouth. In severe cases, the changes can affect other abilities such as speaking, swallowing, and breathing.^1-4

What is myasthenia gravis?

Myasthenia gravis is an autoimmune disorder. This means that the body’s immune system cannot tell the difference between healthy cells and invaders, like viruses or bacteria. Because it cannot tell the difference, the body starts to attack healthy cells.^1-3

MG is a rare disorder that occurs in 1 or 2 of every 10,000 people. It can occur at any age, but it is most common in women under 40 and men over 60.^2-3

Why does myasthenia gravis cause changes in facial expression?

MG is a neuromuscular condition. This means that it affects the muscles – in this case, the muscles of the face. The extraocular muscles (around the eyes) and the bulbar muscles (in the head and neck) may become weak and easily fatigued.^1-3

Because the muscles become weaker and harder to control, a person with MG may notice changes in their facial expressions. Their eyes may droop. Weakness in their lower face may mean they cannot smile or show other expressions. This weakness may affect one or both sides of the face.^1-4

When MG affects the muscles in the face, changes in expression are the most common result. In severe cases, the muscle weakness can also cause problems with speaking, swallowing, and even breathing.^1-2

How are facial changes with myasthenia gravis diagnosed?

MG can be hard to diagnose, especially in minor cases. In general, doctors use a combination of blood tests, physical exams, and electrodiagnostic tests to make a diagnosis. Blood tests may show high levels of pathologic antibodies, but these antibodies are not present in all people with MG.²

Physical exams can check eye movement and coordination. Electrodiagnostic tests can also be used. In these tests, tiny pulses of electricity are sent to the nerves to see how the muscles respond.²

Since 2020, several studies have tried using computer software to measure the changes in facial expression caused by MG. The results have varied since more severe cases are easier to notice.^3-4

What can I do about facial changes?

There is no cure for MG, but your doctor can advise you about various treatment options. These options may include:²

• Medicines to improve messages between the nerves and the muscles
• Immunosuppressant drugs that help prevent production of antibodies
• Medicines to prevent production of certain proteins that can worsen MG
• Surgery to remove the thymus gland, which experts think is linked to MG
• Therapy to remove harmful antibodies
• Gentle exercise to help strengthen muscles

In some cases, MG can go into remission on its own. If this happens, treatment is no
longer needed and facial muscles will likely correct themselves. Remission can be temporary or permanent.²