Abby,

CT's and MRI's are not definitive, especially if done in the first few days after the insult. Also, if done without contrast (dye) the infarct can be difficult to see. Given some time, the infarct will usually show itself as the brain tissue atrophies. I can't tell you how many patients I saw who'd gone into ER with the initial symptoms and were sent home because of a clear CT, only to have a massive stroke shortly thereafter. Not trying to scare you, but if the medical pro's said possible stroke, please know that the chances of a second event are increased in the next weeks and months and it probably would be good for her to be followed up (which it sounds like is happening.)

Hope your aunt continues to recover!