What tests/procedures can detect tia's (mini strokes) in seniors?

Clinical diagnosis. There is no test for tias, or transient ischemic attacks. They look like a stroke, but only last 15 min or less. They can, however, be a warning of an impending stroke, so you need to be evaluated asap.
CT scan. A neurologic exam and a ct scan are needed, though if it is a TIA and not a stroke, the exam findings will improve with time. A stroke would leave a permanent deficit.