Task: Answer Verification
Input (English): Question: Does negative fluid-attenuated inversion recovery imaging identify acute ischemic stroke at 3 hours or less?
Answer: "mismatch" between positive DWI and negative FLAIR allows the identification of patients that are highly likely to be within the 3-hour time window. Within the first 6 hours of stroke, the sensitivity of FLAIR sequences for acute ischemic lesions increases with time from symptom onset elapsing, approximating 100% after 3 to 6 hours.
Output (English): yes