acquired white matter desiese???

[Gayathiri]

hi....
my husband of 27 yrs old over a perriod of time went through a sence of numbness on his left side starting from foot up to chest.This has already happened before about 6 months but disappeared on its own, making this the second episode.After consultation with doctor,we went through a few tests such as MRI,lumbar puncture,VEP,EMG and blood tests.The MRI of spine and the brain with gado was done which showed multifocal patchy hyperintensities involving short segments of the cevical and dorsal chord and the bilateral frontal centrum semiovale, the leftcapsuloganglionic region,periventicular white matter,left caudo-thalmic region,peritrigonal white matter and body of corpus callosum.Few patchy hyperintensities were also seen to involve right superior cerebellarpeduncle,crus cerebri and medulla withot any significant enhansement or diffusion restriction.the cervical chord lesion showed mild emnhansement.The workup for vasculitis was normal.VEPs showed left side optic nerve disfunction.
In view of 2 episodes of dorsal myelopathy with electrophysiological evidnce of left side optic nerve involvement and neuroimaging showing whitematter lesions,the possibility of acquired white matted desiese was considered.He was also detected to have low vitamine B12 and Im suplimentation of the same was started.he was put on long term immunomodulation in the form of mycophenolate.He was also given iv methylprednisolone.
PLease advise the seriousness of the case and accuracy of diagnosis.Is it somthing to be worried about? Might he encounter any problems in future??? what about his left eyesight???
Verry worried.PLease advice.