Dr. Liebeskind said in an interview that the importance of the AAN guideline lay in the fact that it is “one of the first changes in the recommended use of imaging modalities for ischemic stroke since CT was introduced 35 years ago.”
At UCLA, DWI is the preferred imaging modality for diagnosis of acute ischemic stroke. However, he said that in 2010, all imaging modalities should be used as appropriate to refine diagnosis and guide treatment. “At centers that have access to both CT and MRI, it is important to get the most information as fast as possible. Although DWI is more sensitive than non–contrast CT and may be preferred, if the CT scanner is available and MRI is not, go with the CT,” he said.
CT perfusion can give the same information as MR perfusion, Dr. Liebeskind asserted. “I’ve come to see that there is often a routine preference for a given modality at each stroke center, and it varies across sites. Centers seem to excel in the use of the particular imaging modality used most often – CT or MRI.”
He emphasized that imaging studies are an essential component of stroke patient evaluation, and clinicians, whether they are neurologists or not, must quickly interpret and apply the information in real time to make rapid decisions about treatment. “Imaging studies can tell us if it is too late or too risky to institute a particular therapy or guide us to do something fairly aggressive during early phases to reverse any potential neurological injury,” he said.
Dr. Rai serves as a consultant to Boston Scientific Neurovascular and Concentric Medical Inc., which makes neurointerventional products. Dr. Liebeskind is a consultant for Concentric Medical and CoAxia Inc., maker of a perfusion augmentation device. Information about Dr. Sorensen’s disclosures was not available at press time.