michael178

One of the characteristics of Cadasil is an extremely bad MRI, showing extensive diffuse damage that is symetrical, so that both sides of the brain have mirrored damages. The usual cadasil presenting symptoms are migraines, along with typical MS body symptoms. Cadasils is a disease typlifilied by dementia, it is often classified, not as an autoimmune disease, but a vascular disease because damage to the brain is caused by the break down of the walls of micro blood arteries in the deep portion of the brain. The ensuing strokes damage the nerves of the brain, and in later stages, undamaged white matter is hard to find. MS presents with isolated nonsymetrical damage to myelin, usually with a few isolated spots, caused by the body's immune system attacking nerves in the brain.
If you have Cadasil there is no way to have a clean MRI. You will have a clean spinal tap, however.
As for other white matter diseases, next in probability are the family of leukodystrophies, most of which are fatal children's diseases. Less often they strike adults. You might want your neurologist to consider one of these, but they all present with typically bad MRIs, never clean ones. After that, I do not have a clue. Symptoms are so vague, certainly not to you, but to those you attempt to describe them to. The same ones apply to multiple diseases. The best bet is to have your neurologist take his best guess, test the ones that can be tested for, and move on when tests are not conclusive. And it is best for you to simplify your descriptions, how many times for what symptoms, how long they lasted, when they started and when they stopped. Keep a diary, and skip the long narratives. The narratives just confuse the issues at hand.