Diffusion and perfusion MR imaging in acute ischemic stroke: a comparison to SPECT. - J. O. Karonen; Leif Østergaard; P. Vainio; K. Partanen; Ritva Vanninen; E. Vanninen; Katja Korhonen; S. Haapamäki; Y. Liu; Reina Roivainen (Comput. Methods Programs Biomed., 2001)