Be careful what you wish for! By that, I mean listening to people dx stories!!

No two cases of MS are ever alike, they are like fingerprints, individual to each case..so, youre getting more than you bargained for asking for that information to be shared!

But its a good question. Youll get lots of posts.
First of all, welcome to our board. We are a wealth of information....if you use the search engine above, specifically for Healthboards, and type in key words like MS dx youll get TONS of posts on this.
Im not going to bore you with my story, instead Ill just give you some facts. For some people, it takes YEARS to get a MS dx. For others, (like me) the diagnosis comes in a matter of weeks. It depends on what the MRI shows at the first round of testing, and also how your doctor proceeds. Let me suggest that you see a good MS doctor, not a regular Neurologist. Youll get a faster answer on YES or NO to MS. You asked how good an MRI is as a diagnostic tool. AT this time, its one of the few available. You can do a LP (lumbar puncture or spinal tap) which is usually done to confirm MS- O-bands show in the spinal fluid....however, in two years any NUMBER of things could change in an MRI. You should be getting another one for comparison sake. I have over 50 legions in my brain. Normally both a brain and spine are MRI'ed in the beginning. Legions can show in either place. Legions, are scar tissue. Formed by the disease itself. As the disease attacks the myelin sheath, the legions are formed...so, they show as white matter on an MRI. BUT, white matter and scar tissue can also be formed by head trauma or even migranes, so just having them isnt enough, They are usually specifically in certain areas of the brain, and in a certain pattern. THere is specificic criteria used to determine if MS is a possiblity. Apparently, you didnt meet that criteria 2 years ago.
At this time, though, what you describe definately sounds neurological. You should seek a good Neurologist and as I suggested earlier, you might want to try to get an appt with an MS specialist to start further evaluation. Your doctor may NOT have ruled it out too early, but in two years LOTS can and probably has changed...
Wishing you luck. Please ask questions if anything I said, you arent understanding..
Nikki