title: Effects of radiation dose reduction in Volume Perfusion CT imaging of acute ischemic stroke.
abstract: To examine the influence of radiation dose reduction on image quality and sensitivity of Volume Perfusion CT (VPCT) maps regarding the detection of ischemic brain lesions.
  
  
  
  VPCT data of 20 patients with suspected ischemic stroke acquired at 80 kV and 180 mAs were included. Using realistic reduced-dose simulation, low-dose VPCT datasets with 144 mAs, 108 mAs, 72 mAs and 36 mAs (80 %, 60 %, 40 % and 20 % of the original levels) were generated, resulting in a total of 100 datasets. Perfusion maps were created and signal-to-noise-ratio (SNR) measurements were performed. Qualitative analyses were conducted by two blinded readers, who also assessed the presence/absence of ischemic lesions and scored CBV and CBF maps using a modified ASPECTS-score.
  
  
  
  SNR of all low-dose datasets were significantly lower than those of the original datasets (p < .05). All datasets down to 72 mAs (40 %) yielded sufficient image quality and high sensitivity with excellent inter-observer-agreements, whereas 36 mAs datasets (20 %) yielded poor image quality in 15 % of the cases with lower sensitivity and inter-observer-agreements.
  
  
  
  Low-dose VPCT using decreased tube currents down to 72 mAs (40 % of original radiation dose) produces sufficient perfusion maps for the detection of ischemic brain lesions.
  
  
  
  • Perfusion CT is highly accurate for the detection of ischemic brain lesions • Perfusion CT results in high radiation exposure, therefore low-dose protocols are required • Reduction of tube current down to 72 mAs produces sufficient perfusion maps.
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany. ahmed.e.othman@googlemail.com.|Department for Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany. ahmed.e.othman@googlemail.com.
authors.forename: Ahmed E
authors.initials: AE
authors.lastname: Othman
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Brockmann
authors.affiliation: Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Suwon, 433-270, South Korea.|Department of Radiology, Seoul National University College of Medicine, Seoul, 110-744, South Korea.
authors.forename: Zepa
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Suwon, 433-270, South Korea.|Department of Radiology, Seoul National University College of Medicine, Seoul, 110-744, South Korea.
authors.forename: Changwon
authors.initials: C
authors.lastname: Kim
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany.
authors.forename: Saif
authors.initials: S
authors.lastname: Afat
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany.
authors.forename: Rastislav
authors.initials: R
authors.lastname: Pjontek
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany.
authors.forename: Omid
authors.initials: O
authors.lastname: Nikoubashman
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Brockmann
authors.affiliation: Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Suwon, 433-270, South Korea.|Department of Radiology, Seoul National University College of Medicine, Seoul, 110-744, South Korea.|Center for Medical-IT Convergence Technology Research, Advanced Institute of Convergence Technology, Suwon, 433-270, South Korea.
authors.forename: Jong Hyo
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Wiesmann
mesh_terms: D000368:Aged; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D015588:Observer Variation; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D059629:Signal-To-Noise Ratio; D020521:Stroke / Q000000981:diagnostic imaging*
keywords: Low dose perfusion CT, Perfusion CT, Perfusion imaging, Radiation dose; Stroke