Magma: Magma, molten or partially molten rock from which igneous rocks form. It usually consists of silicate liquid, although carbonate and sulfide melts occur as well. Magma
There are three main types of stroke: transient ischemic attack, ischemic, and hemorrhagic. Itâs estimated that 87 percent of strokes are ischemic. Doctors also call a transient ischemic attack (TIA) a warning or ministroke. A clot that temporarily blocks blood flow to your brain causes a TIA.
The two types of hemorrhagic strokes are intracerebral (within the brain) hemorrhage or subarachnoid hemorrhage. Hemorrhagic stroke occurs when a weakened blood vessel ruptures. Two types of weakened blood vessels usually cause hemorrhagic stroke: aneurysms and arteriovenous malformations (AVMs). View a detailed animation of hemorrhagic stroke. 1  An aneurysm is a ballooning of a weakened region of a blood vessel. If left untreated, the aneurysm continues to weaken until it ruptures and bleeds into the brain. 2  An arteriovenous malformation (AVM) is a cluster of abnormally formed blood vessels.