I have been having lightheadedness for a while. Would a CT of head and an MRI with contrast of brain detect blockages in arteries?
Might, but has high . Head ct/mr may should arterial blockage. Would be better seen with brain mra.
No. Assuming the other more common causes of lightheadedness such as medication, etc. Have been excluded...A cta (ct angiogram) of the head and neck should show any arterial narrowing/blockage. An mra of the head and neck (no contrast) will similarly show arterial narrowing. Ct head without contrast will only show calcific atherosclerosis and MRI brain with contrast is not used to evaluate arteries.