This is a study of the blood vessels of the brain. With this information the exact size and configuration of the neck and dome of the aneurysm can be determined. A consultation with a neurosurgeon should then be obtained. There are risks and benefits with each method of treatment, and these should be discussed with your neurosurgeon. A magnetic resonance imager is capable of showing both nerves and blood vessels.
Most newer scanners can perform magnetic resonance imaging, and magnetic resonance angiography .
These are non-invasive studies and should provide the information that you seek. An arteriovenous malformation is an abnormal association of arteries and veins which has less resistance than normal capillaries. More blood flows through the vessels leading to this low resistance malformation, and as such, these vessels are more likely to develop an aneurysm. It is difficult to determine the actual percentage increase risk, but someone with an untreated AVM should be monitored by a neurosurgeon who can watch for the development of an aneurysm on a vessel leading to the malformation, or on a vessel within the malformation. Either of these increases the risk of subsequent hemorrhage which can be eliminated with proper treatment.