Is Devic's disease a type of multiple sclerosis?

Is Devic's disease a type of multiple sclerosis?

Until recently, Devic's disease was thought to be a kind of MS that caused more severe problems with the optic nerves and spinal cord. Recent research has suggested that Devic's disease is probably a different disease in which there is a specific immune attack on a molecule known as aquaporin 4. Our understanding of Devic's disease is changing quickly at the present time due to new research in this important disorder.