Mri,cat scan versus angiogram

Some were saying that mri's and cat scans don't always pick up avms. Does anyone know why these scans wouldn't pick them up and an angoigram would.

Hi Patricia,

I think the difference is that the angio is better able to isolate the area of interest from all the tissue surrounding it, and I think it also allows the doctor to track the rate of blood flow. That's just my best guess...but I can say for sure that the angio is definitely considered a better test for AVMs than CT or MRI is.

There are also CT-Angio and MR-Angio tests, where you have the CT or the MRI with a contrast dye. It's not as good as the angio, since it can't target the exact area of interest, but it's better than CT or MRI without dye, and less invasive than an angio.


Hi Patricia. Check this website out and scroll down to number 7…
And you may wish to check out this site too…
I do know there are several members here whose AVMs could only be seen by way of an angiogram.

Thank you JH,

I had a mri which showed my brain was clear, they did not use the dye. I thought I was in the clear but maybe not. I sometimes hear blood running through my head which the doctor said was not normal so I thought I must hear it from my tongue. The doctor said there was no way I would be hearing it from my tongue.


Thank you Barbara,

We can always count on you with your wealth of knowledge.


Every scan has his own specialisation, on the one scan you can see certain things better as with the other scan. I think an MRI is very general. I'm having a MRA in May.. it's an MRI that visualize blood vessels. When you search it up, you'll see that there are more different MRI's, all with their own specialization.
But I heard that angiograms are the best way to see the bloodvessels/AVM's etc. Because of the contrast the docs can see very specific how the blood flows trough the vessels and how fast it flows.

I hope this helps you a little bit.