Can brain aneurysms be found with ct scan and contrast or must mri be used to diagnose. i was told my a&e ct scan with contrast 20 yrs ago showed good blood vessels as my brother was recently diagnosed with aneurysms would i need tests again?

Both can be used to diagnose brain aneurysms. If you are worried or have a strong family history then have it done.

Although resolution may vary amongst CAT scans, CTA's, MRI's, and MRA's, any or all can identify suspicious lesions consistent with a significant aneurysm. If your brother's aneurysm is a congenital berry type, unlikely with your history that you will also have. But if you, or a family member, has polycystic kidney disease, then, screening is important. Inquire about this situation.