title: Hyperperfusion and enhancement in dynamic computed tomography of ischemic stroke patients.
abstract: The passage of contrast medium was observed using serial computed tomography (CT) in 24 stroke patients. Density--time profiles of various brain regions were plotted. In normal brain tissue, X-ray attenuation showed a maximum increase during the arterial phase (16.4 +/- 11.0%) and was 2.8 +/- 2.2% above control during stable distribution. In hypoperfusion, increase in attenuation was always below 10% in the arterial phase, while hyperperfusion was characterized by an attenuation increase of 25 to 70%. Enhancement was defined by a density increase of 16.8 +/- 14.8% and a tissue/blood ratio between 7 and 60%. An attempt was made to establish a relationship between the serial CT pattern and the prognosis. Enhancement tended to indicate severe morphological changes followed by permanent neurological deficit, whereas hyperperfusion was generally an indicator of probably recovery.
mesh_terms: D000328:Adult; D000368:Aged; D001812:Blood-Brain Barrier; D001921:Brain / Q000000981:diagnostic imaging; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging*; D006801:Humans; D007482:Iothalamate Meglumine / Q000031:analogs & derivatives / Q000378:metabolism; D002546:Ischemic Attack, Transient / Q000000981:diagnostic imaging*; D008875:Middle Aged; D010477:Perfusion; D011856:Radiographic Image Enhancement / Q000379:methods*; D014057:Tomography, X-Ray Computed
chemical_list: D007482:Iothalamate Meglumine