The word "aneurysm" comes from the Greek word meaning "to dilate." An aneurysm in the medical sense is a dilation or ballooning out of a blood vessel. When this happens, the vessel wall becomes thinner. As such, with certain insults (such as high blood pressure), the vessel wall may rupture. Aneurysms can be anywhere although the ones that we frequently hear about are either in or around the brain or of the aorta (largest artery coming off of the heart). In your mother's case, it sounds like they were concerned that an aneurysm of one of the vessels that supply blood to her brain had ruptured. This can cause people to act weird and can be considered one of the two types of stroke; this one is hemorrhagic (bleeding), the other kind is thrombotic (clot). Certain head imaging studies (like CT or MRI) can see blood in different places and at different times. Oftentimes, aneurysms stop bleeding on their own, as the vessels "know" that something is wrong. If there is continual bleeding, an interventional neurologist
or a neurosurgeon
can put small clips on the aneurysm to stop the bleeding. Other options include embolization (clotting) of the aneurysm by inserting small coils into the aneurysm that make blood clot there. I hope that this helps answer your question. As always, no doctor
can examine you over the Internet or telephone, so always erring on the side of caution and seeing a physician if you are concerned is the best course of action.