MRI w/out contrast

Hello! Just had a question about MRIs. I had a brain and cervical MRI but when it came time to insert the contrast, they couldn't get it in my vein. (I'm a pain to stick). The room was so cold, I was shivering badly, and they had stuck me a few times... so the techs called the dr and asked if they could just finish without.

My question is - I have a clear MRI. I have a lot of neuro symptoms and am in the beginning of my diagnosis journey, but I wonder ... how important is that contrast when looking for lesions, etc?

Thanks all!

From what I understand, contrast identifies "active" lesions--ones that are currently experiencing inflammation. Non-contrast MRIs will still show all lesions but won't identify if any are active or not.