Mri scan

I wonder if someone on here could advise. I was diagnosed with RRMS approximately 2 years ago, now on Tec. At my last nurse appointment I asked if the mri I’d had a little while ago had been reported on. Apparently it had, the good news is I’m classed as stable, with no new additional lesions compared to the last scan. However, the report now mentions I have a few black holes, I don’t think this has been mentioned on earlier mri reports and I was just wondering if anyone on here would kindly explain. I’m due to see the neuro in a month and was going to ask then, but it would be great if anyone could advise in the meantime.

thanks in advance.