The recently published article by Röther et al1, a prospective study on computed tomographic perfusion imaging (pCT) in a "consecutive clinical series of 22 patients," is the second prospective study on pCT in acute ischemic stroke published by this group of authors within a year.2 Although the authors mentioned that "some patients were included in a previous study that validated the CTP [pCT] methods,"2 they did not provide a reference for the previous study, even though the first article appeared before the second was finally accepted for publication. Because the authors do not present the exact number of patients whose data were used for both publications, it remains unclear how broad the basis for the data was for both studies.
von Kummer R. CT Perfusion: Two Publications, Same Patients, Different Results. Arch Neurol. 2001;58(5):835-837. doi: