Acute stroke is one of the leading causes of death, dementia and disability all over the world [AHA Heart Disease and Stroke Statistics update, 2012]. The aim of the study: To characterize brain perfusion in acute cerebral ischemic stroke with and without atherosclerotic changes in brachiocephalic blood vessels, using multimodal computed tomography examination, and to determine the role of imaging in the diagnostic algorithm and the selection of therapy. The author personally participated in all stages of the research - in the study design, the collection of data, computed tomography examination and data post-processing, statistical analysis, interpretation of the results obtained, literature review, preparation of publications, theses, conferences reports, and translation. She is also the author of the published images. This combined (cross-sectional prospective and group-control retrospective) study was approved by the Ethics Committee at Riga Stradins University and the Scientific Department at Pauls Stradins Clinical University Hospital. sakriti opis