− | Myasthenia gravis is a disease of the neuromuscular junction that occurs due to a defect or absence of nicotinic acetylcholine receptors on the post-synaptic membrane (in the congenital form) or due to the presence of antibodies that bind to the receptors and prevent them from functioning normally (in the acquired form). Acquired myasthenia Gravis is the most common form of the disease. The classical '''focal''' form of myasthenia gravis affects only the extraocular muscles, the cranial oesophagus and the muscles innervated by cranial nerves V, VII and IX. 80% of animals diagnosed with myasthenia gravis have megaoesophagus at presentation. | + | Myasthenia gravis is a disease of the neuromuscular junction that occurs due to a defect or absence of nicotinic acetylcholine receptors on the post-synaptic membrane (in the congenital form) or due to the presence of antibodies that bind to the receptors and prevent them from functioning normally (in the acquired form). Acquired myasthenia Gravis is the most common form of the disease. The classical '''focal''' form of myasthenia gravis affects only the extraocular muscles, the cranial [[Oesophagus - Anatomy & Physiology|oesophagus]] and the muscles innervated by [[Cranial Nerves - Anatomy & Physiology|cranial nerves]] V, VII and IX. 90% of animals diagnosed with myasthenia gravis have [[Megaoesophagus|megaoesophagus]] at presentation. |