What can a mra detect that a brain mri cannot detect?

Vascular disease: Mra looks at moving blood in the arteries of the brain and can help in the diagnosis of vascular narrowing from atherosclerosis, or anerysms, and arteriovenous malformations (avm). Though an MRI may detect large aneurysms and if contrast is given suggest avm, mra is much more sensitive than MRI when investigating vascular anatomy. Mra does have its limits, small aneurysms can't be detected.

MRA shows arteries: Mr angiography (mra) is an MRI which uses special sequences/techniques to highlight the arteries in the area scanned to look for abnormalities such as aneurysms. Like any test, it is not 100% accurate, but performed correctly and interpreted by a qualified radiologist, it is a great test to screen for arterial abnormalities.

Vascular disease: In a standard set of MRI images, the blood vessels can be tortuous or poorly seen, and this can obscure blood vessel diseases such as dissection, occlusion and aneurysm. This limitation can be overcome with special techniques, especially on the newest MRI machines. However, almost all the MRI machines can do MRA studies, with or without IV contrast, for a better evaluation of the blood vessels.