My uncle had a stroke and hasn't woken up in almost a week. what's the difference between a normal and severe stroke?

So sorry: A severe stroke is one in which you don't wake up. My deepest sympathy.

Most serious: The level of seriousness depends on the size and effects of the stroke. Strokes may be very small,medium-sized, or they can be large and cause many, serious symptoms, including loss of consciousness. Sometimes even a small stroke can cause serious symptoms if it affects a small, important area. As my colleagues have stated, may you have my deepest sympathy.