How can you tell if someone had a stroke without an MRI?

A fellow caregiver asked...

If a person has a pacemaker and cannot have an MRI, are there any other ways to determine if they had a stroke?

Expert Answer

James Castle, M.D. is a neurologist at NorthShore University HealthSystem (affiliated with The University of Chicago) and an expert on strokes.

Aside from the physicians clinical impression, another diagnostic approach would be to get a CT of the brain. These are not nearly as good as MRI scan for detecting small strokes, but can be helpful, particularly if the stroke is large. Roughly 48 hours onset of symptoms, a CT should detect about 1/2 to 2/3 of all ischemic strokes (as opposed to bleeding strokes). Prior to 48 hours, that number is smaller, approaching 0 if done immediately at the onset of symptoms.

As you can see, CT can sometimes be helpful, but should not be relied upon entirely if MRI is not possible. A good clinician's judgement, however, when used in combination with a CT, should detect most strokes.