title: Reducing radiation dose in the diagnosis of pulmonary embolism using adaptive statistical iterative reconstruction and lower tube potential in computed tomography.
abstract: OBJECTIVE
  To assess the impact of ASIR (adaptive statistical iterative reconstruction) and lower tube potential on dose reduction and image quality in chest computed tomography angiographies (CTAs) of patients with pulmonary embolism.
  
  
  METHODS
  CT data from 44 patients with pulmonary embolism were acquired using different protocols-Group A: 120 kV, filtered back projection, n = 12; Group B: 120 kV, 40 % ASIR, n = 12; Group C: 100 kV, 40 % ASIR, n = 12 and Group D: 80 kV, 40 % ASIR, n = 8. Normalised effective dose was calculated; image quality was assessed quantitatively and qualitatively.
  
  
  RESULTS
  Normalised effective dose in Group B was 33.8 % lower than in Group A (p = 0.014) and 54.4 % lower in Group C than in Group A (p < 0.001). Group A, B and C did not show significant differences in qualitative or quantitative analysis of image quality. Group D showed significantly higher noise levels in qualitative and quantitative analysis, significantly more artefacts and decreased overall diagnosability. Best results, considering dose reduction and image quality, were achieved in Group C.
  
  
  CONCLUSIONS
  The combination of ASIR and lower tube potential is an option to reduce radiation without significant worsening of image quality in the diagnosis of pulmonary embolism.
  
  
  CONCLUSIONS
  • Iterative algorithms and lowering of tube potential reduce radiation without compromising interpretability • 40 % ASIR and 100 kV tube potential led to a 54.4 % dose reduction • 40 % ASIR and 80 kV tube potential led to significantly worse image quality.
authors.affiliation: Department of Radiation Oncology, Charité School of Medicine and University Hospital, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany, david.kaul@charite.de.
authors.forename: David
authors.initials: D
authors.lastname: Kaul
authors.forename: Ulrich
authors.initials: U
authors.lastname: Grupp
authors.forename: Johannes
authors.initials: J
authors.lastname: Kahn
authors.forename: Pirus
authors.initials: P
authors.lastname: Ghadjar
authors.forename: Edzard
authors.initials: E
authors.lastname: Wiener
authors.forename: Bernd
authors.initials: B
authors.lastname: Hamm
authors.forename: Florian
authors.initials: F
authors.lastname: Streitparth
mesh_terms: D000368:Aged; D000465:Algorithms; D016477:Artifacts; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*