• Frank hypointensity (i.e. dark hue) on CT of the brain, particularly if involving greater than one-third of the middle cerebral artery (MCA) territory, is a contraindication to treating acute ischemic stroke with tPA.

• Early signs of infarct on brain CT, regardless of extent, are NOT contraindications to treatment.

References

• Latchaw et al.  Recommendations for imaging acute ischemic stroke:  A scientific statement from the American Heart Association. Stroke 2009;40:3646-78.