Can I Prevent Ocular MG From Progressing to Generalized MG?

Ocular myasthenia gravis is a type of myasthenia gravis (MG) that mainly affects the eye and eyelid muscles. If you have ocular MG, you may be concerned about developing generalized MG. With generalized MG, weakness can occur in many other muscles in the body.¹

What are the symptoms of ocular MG?

Eye problems are a common early sign of both ocular and generalized MG. For people with generalized MG, muscle weakness may gradually spread to other muscles in the face, arms, or legs. Unlike generalized MG, people with ocular MG do not have muscle weakness in other parts of the body.^1,2

Ocular MG causes the eye muscles to get tired and weak easily. People with ocular MG may have vision problems due to drooping eyelids and double vision. Symptoms can vary from mild to severe and tend to get worse at the end of the day. However, vision problems may improve after rest.¹

Does ocular MG commonly progress to general MG?

Ocular MG can progress to generalized MG, but experts do not know exactly how likely this is. Estimates of how many people with ocular MG progress to generalized MG vary widely, from 20 to 85 percent of cases.^1,2

In general, the risk of progression from ocular MG to generalized MG varies according to how long you have had MG symptoms:^1,2

• 1 year – About half of people with eye symptoms related to MG will develop generalized MG within 1 year.
• 5 years – Most people with only eye symptoms after 5 years will not progress to generalized MG.
• Overall – About 15 percent of people with MG will have only ocular MG.

Risk factors that may make people more likely to progress to generalized MG include:²

• Positive blood test for acetylcholine receptor (AChR) antibodies
• Abnormal thymus gland
• Age over 50
• Severe symptoms
• Abnormal nerve stimulation tests

People of Asian descent seem to have a lower risk of progression compared to the general population.²

How is ocular MG treated?

The most common treatment for ocular MG is a medicine called pyridostigmine. The brand name of this drug is pyridostigmine (MestinonⓇ). This drug treats the symptoms of ocular MG, but it does not affect the progression of ocular MG to generalized MG.^1,3

Oral steroids, like prednisone and prednisolone, are often used to treat ocular MG if pyridostigmine is not effective. People with milder symptoms tend to respond better to steroids. It can take several months of steroid treatment before eye symptoms resolve.³

Doctors may recommend additional immunosuppressive drugs for people whose symptoms do not respond to pyridostigmine or steroids. Other treatment options for persistent ocular MG symptoms may include:^1,2

• Thymus gland removal
• Eye patch or eyelid taping
• Dark glasses
• Eyeglass prisms
• Eye surgery

Can I prevent ocular MG from progressing to generalized MG?

Some studies suggest that the steroid prednisolone and other immunosuppressive therapies may reduce the risk of ocular MG progressing to generalized MG. However, there is limited research on the impact of steroids and other immunosuppressive drugs on changing the natural course of ocular MG. To address this, randomized clinical trials of immunosuppressive therapies in ocular MG are needed.^1,2,4

How do I know if ocular MG is progressing to generalized MG?

Muscle weakness in other areas of the body could be a sign of progression. Talk to your doctor right away if you experience the following symptoms:⁵

• Trouble speaking, chewing, or swallowing
• Trouble moving your neck or holding your head up
• Weakness in the arms or legs
• Trouble walking
• Breathing problems