title: Shortened Mean Transit Time in CT Perfusion With Singular Value Decomposition Analysis in Acute Cerebral Infarction: Quantitative Evaluation and Comparison With Various CT Perfusion Parameters.
abstract: OBJECTIVE
  We aimed to clarify the cause of shortened mean transit time (MTT) in acute ischemic cerebrovascular disease and examined its relationship with reperfusion.
  
  
  METHODS
  Twenty-three patients with acute ischemic cerebrovascular disease underwent whole-brain computed tomography perfusion (CTP). The maximum MTT (MTTmax), minimum MTT (MTTmin), ratio of maximum and minimum MTT (MTTmin/max), and minimum cerebral blood volume (CBV) (CBVmin) were measured by automatic region of interest analysis. Diffusion weighted image was performed to calculate infarction volume. We compared these CTP parameters between reperfusion and nonreperfusion groups and calculated correlation coefficients between the infarction core volume and CTP parameters.
  
  
  RESULTS
  Significant differences were observed between reperfusion and nonreperfusion groups (MTTmin/max: P = 0.014; CBVmin ratio: P = 0.038). Regression analysis of CTP and high-intensity volume on diffusion weighted image showed negative correlation (CBVmin ratio: r = -0.41; MTTmin/max: r = -0.30; MTTmin ratio: r = -0.27).
  
  
  CONCLUSIONS
  A region of shortened MTT indicated obstructed blood flow, which was attributed to the singular value decomposition method error.
authors.affiliation: From the *Department of Radiology, Fujita Health University; †Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University; and ‡Department of Neurosurgery, Fujita Health University, Toyoake, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Murayama
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Katada
authors.forename: Motoharu
authors.initials: M
authors.lastname: Hayakawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Toyama
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging / Q000503:physiopathology; D001931:Brain Mapping / Q000379:methods; D002533:Cerebral Angiography / Q000379:methods*; D000071937:Cerebral Blood Volume / Q000502:physiology*; D002544:Cerebral Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D038524:Diffusion Magnetic Resonance Imaging; D005069:Evaluation Studies as Topic; D005260:Female; D006351:Heart Valves / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*