Introduction: I was wrong

Neurointerventionists are on the cusp of revolutionizing the care of the acute ischemic stroke patient. The stage is set for a major advance after 2 decades of experience and the development of extraordinarily effective endovascular devices. This advance depends on a clear demonstration of improved patient outcomes, but the evidence for improved outcomes after endovascular therapy is weak. This was most dramatically demonstrated by the halting of the IMS III trial (ClinicalTrials.gov Identifier: NCT00359424). There is an emerging consensus that the proper selection of patients for endovascular treatment has been lacking. Patient selection using neuroimaging has not been successful, most likely because ineffective neuroimaging methods have been employed.

I have been a strong advocate of using neuroimaging, especially CT perfusion (CTP), for patient selection. CTP is particularly attractive because it can be obtained immediately after non-contrast CT and C without moving the patient. But I was wrong. There is now strong evidence that some neuroimaging methods are effective but others are not. I have learned that the evidence is especially strong for the reliability of diffusion MRI and the unreliability of CTP for measuring the size of the infarct core in the individual patient. In this essay, I review the evidence that led to my current view on the best practices for imaging the stroke patient. My hope is that my education may help neurointerventionists maximally benefit their patients.