Unfortunatley I don't know where it is for sure. Dad will find out in a few days when he has a meeting with the neurosurgeon. I know it's 4mm by 5mm saccular towards the rear of the brain on the left side... I'm not sure what artery it's on at all. The neurosurgeon said something about he would be using the brain's rear arteries to push the coiling through to the aneurysm and that is why he wants the carotid cleared because the front arteries will need to be working at their fullest. We first thought they would be doing clipping but he seems to be leaning towards coiling now. I don't have any records as they are at my dads place.

So I still haven't found out exactly on what artery the aneurysm is located but it is near the left ear and actually embedded in the brain. They are going to do an angiogram on him to see more detail about it because they are not sure if they can even operate on it as they think it might be too risky.

I have found out it's on the middle cerebral artery. If that is not enough information, he is going for an angiogram on Tuesday so they can get better detail of the aneurysm then. Is it possible for me to leave this question open for a few days until I have more details about it? I would appreciate it so much.