Your imbalance can originate from the beginnings of myelopathy but can derive from peripheral neuropathy. See the website for an explanation of this disorder.
I never like to understand an image of an MRI from someone else’s description as their choice of works does not paint a picture for me. If there is a rind of CSF around the cord at every level including the “tight” level and the cord is not deformed, the stenosis at that level would be considered “mild” in my classification scheme. Cord deformation or loss of one sided CSF would make the stenosis “moderate” in my reading.