Hello. I'm Dr. Christensen.
I'm sorry your father is having problems. His symptoms are very suspicious for a transient ischemic attack
(TIA) or resolving ischemic neurologic deficit
(RIND). The primary difference between these two conditions is their duration: TIAs last less than 24 hours, while RINDs last from 24 to 72 hours. Both are caused by an interruption in the blood flow to the brain, and both could herald an oncoming stroke
. CT scans don't detect these problems; in fact, a CT won't detect a full-blown stroke if it is performed within 24 hours or so of symptom onset (unless the stroke is accompanied by bleeding).
Your father's CT indicates that he already has some cerebrovascular disease
(a lacunar infarct is a very small stroke) although it sounds like his scan looks remarkably good for a 90-year-old man. However, his longstanding diabetes
places him at risk for a stroke, and the episode he experienced at 4:30 pm could be an indication a stroke is about to occur.
Further evaluation is warranted here. Your father should see his doctor again to discuss whether he needs a carotid ultrasound
, an echocardiogram
(an ultrasound of the heart), or other tests or treatment to protect him from a more serious event.
I hope that answers your question, and I hope your father does well!