I can really sympathise with you. I first went to a neuro in 2005 with numbness. MRIs an LP negative. I had an attack in 2008 but GP would not refer me to neuro as all scans had been clear. With the development of footdrop in 2010 I eventually saw a neuro in 2011 and lesions were seen on my spinal cord - brain & LP were again clear. I was told I was suffering from delayed radiation myelopathy from cancer treatment that I had in 1990. In 2012 I saw a different neuro as I was referred from the private sector into the NHS. New neuro said not radiation myelopathy but I had had transverse myelitis. In 2012 I did have one small brain lesion seen but the LP was still negative. My scans in 2013 and 2014 were stable and I had no new symptoms. In 2015 I started B12 injections and gradually all my sensory symptoms cleared up but I still had the foot drop. In 2016 I heard about HSCT. I asked my neuro and he just laughed saying that I did not have MS. So I went down to London and saw one of the BARTs neuros and he looked at my scans and reports and said that I had MS and it had been clear from 2011 - even though I did not make the McDonald criteria. He wanted me to go on a DMD. So I went back to my own NHS neuro and he said I did not satisfy the criteria for the drug and he still said this was not MS.
But with the DX of MS from the London neuro I applied to Mexico. I had an MRI before I went, took the disc with me and the neuro was shaking his head as the large lesions on my cord were no longer visible on the scan. I had brought a copy of older ones for him to compare and he was confused. The one small lesion was still there. He said that MS could not have caused the cord lesion as it would not have repaired so well - but however he did say the brain lesion was typical of MS and maybe whatever had first happened in the spine had cause the MS. I reckon the B12 has helped me.
If I were you before you have any permanent damage get them to give you B12. B12 deficiency can cause PPMS type symptoms. I would not be happy with an injection 4 times a year. I do mine myself once a week. Too much of B12 will do you no harm. Dont go by blood work as mine was fine I just pressurised them to give me the injections and it has paid off. If you have difficulty go on the Pernicious Anemia website. People go to Wales to see a doctor there who can give you a transfusion of B12 and then supply you with treatment that you can inject yourself. I went there and felt that I was trasformed after the infusion which is why P presuaded my neuro to precribe me the weekly injections. I have been left with the foot drop as I was not treated early enough. The axons had been left to exposed due to demyelination for too long.
Finally, buy the book “Could it Be B12”
What symptoms are you having?