Hi there. Unruptured cerebral aneurysm can be investigated with cerebral arteriogram or angiogram. A doctor inserts a long thin tube into an artery in your legs and guides it through your blood vessels to the arteries in your neck that lead to your brain. A specialist injects dye into the arteries, which creates a map of your arteries and the aneurysm on xrays. CT can reveal blood flow in your brain and show aneurysm location. Sometimes a dye may be injected into a vein to highlight blood flow in your arteries and veins, CT angiogram and provide additional detail regarding appearance of brain aneurysm. MRI can create detailed images of your brain and show aneurysm’s location. Hope this helps. Take care.
In general, a contrast MRA will provide far more detailed information. A dye contrast scan is the appropriate method of ruling our an aneurysm. There are fewer side effects from the dye used in an MRA than with the dye used in a CT scan.
There are few risks with a dye-contrast MRA, and if your neurologist feels this is necessary do not hesitate to undergo the procedure. Often the protocol is recommended for cranial nerve palsy's (one eye being frozen in position) to determine if the cause is an aneurysm.