Myasthenia gravis is an autoimmune neuromuscular disorder that causes fluctuating muscle weakness, often affecting the eye and eyelid muscles first. It results from impaired communication between nerves and muscles at the neuromuscular junction.
Ocular Features
Common eye-related symptoms include variable drooping of one or both eyelids and double vision that worsens with sustained use of the eyes. Symptoms typically improve with rest and may fluctuate throughout the day.
- Ptosis and diplopia can change in severity from hour to hour
- Brow or head posture may adjust to compensate for drooping lids
- Pupils are usually normal, helping distinguish from other conditions
- Some patients develop more generalised muscle weakness over time
Diagnosis and Treatment
Diagnosis involves clinical examination, blood tests for specific antibodies, electrophysiological studies, and sometimes pharmacological tests. Treatment aims to improve neuromuscular transmission and modulate the immune response, using medications such as acetylcholinesterase inhibitors and immunosuppressive agents.
- Thymus imaging may be performed to look for thymic enlargement or thymoma
- Crisis with breathing or swallowing difficulty is a medical emergency
- Regular monitoring adjusts therapy according to symptom control
- Eye-specific measures such as prisms or eyelid supports may relieve diplopia and ptosis
