3D Brain MRI
The lesion in my brain that diagnosed me with PPMS, has not moved or grown in size. Blessing.
But my sinuses showed up on my MRI
And neurologist advised only come in once a year for another MRI
Less monitoring of it is not sitting well with me ...

I have PPMS and only get an MRI anytime I have new or worsening symptoms. That ends up being every 2-3 years. I think that the symptoms are more telling than the MRI. I don't think that monitoring a lesion more often will provide much value unless you're having issues. So, I wouldn't worry about doing it only once a year.
@Karen51 thank you for making it more clear.