1 If a lot of blood leaks out, it can cause a buildup of pressure in the brain because the brain is enclosed in the skull. There is no room for brain tissue to expand, and so the leaked blood can compress and kill important areas of the brain.  Hemorrhagic strokes tend to be more serious than ischemic strokes.
Horizontal definition, at right angles to the vertical; parallel to level ground. See more.
Vertically definition, being in a position or direction perpendicular to the plane of the horizon; upright; plumb. See more.