title: Individually tailored contrast enhancement in CT pulmonary angiography.
abstract: OBJECTIVE
  The purpose was to evaluate individually shaped contrast media (CM) delivery in CT pulmonary angiography (CTPA) for suspected pulmonary embolism (PE).
  
  
  METHODS
  100 consecutive emergency patients with clinical suspicion of PE were evaluated. High-pitch CTPA was performed on a second-generation dual-source CT using the following parameters: 100 kV, 200-250 mAsref, rotation time 0.28 s, 128 × 0.6 mm col. and image reconstruction 1.0/0.8 mm (B30f). Group 1 (n = 50) then received a fixed CM bolus (300 = mgI ml(-1), volume = 90 ml and flow rate = 6 ml s(-1)); Group 2 (n = 50) received a body weight-adapted CM bolus determined by dedicated contrast injection software. For analysis, groups were further subdivided into low-weight (40-75 kg) and high-weight (76-117 kg) groups. Technical image quality was graded using a four-point Likert scale (1 = non-diagnostic; 2 = diagnostic; 3 = good and 4 = excellent image quality) at the level of the pulmonary trunk and pulmonary arteries. Objective image quality analysis was performed by measuring contrast enhancement in Hounsfield units (HU) at the same levels. Attenuation levels > 180 HU were considered diagnostic.
  
  
  RESULTS
  All examinations were graded as diagnostic at each level. The individual minimum pulmonary attenuation was 184 and 270 HU for Group 1 and 2, respectively. Mean attenuation was as follows: Group 1: 475 ± 105 HU (40-75 kg) and 402 ± 115 HU (76-117 kg), p < 0.03. Group 2: 424 ± 76 HU (40-75 kg) and 418 ± 100 HU (76-117 kg), p = 0.8. For Group 2, CM volumes were: 55 ± 5 ml (40-75 kg) and 66 ± 5 ml (76-117 kg), leading to 16-51% CM reduction.
  
  
  CONCLUSIONS
  Even under emergency conditions, individualized CM protocols can provide diagnostic and robust image quality in CTPA for PE with a substantial reduction of CM volume for lower weight patients, compared with a fixed CM protocol.
  
  
  CONCLUSIONS
  CM volume can substantially be reduced by using individualized CM protocols in CT angiography for PE without compromising the diagnostic image quality.
authors.affiliation: 1 Departments of Radiology, Maastricht University Medical Center, Maastricht, Netherlands.|2 CARIM School for Cardiovascular Diseases, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Babs M F
authors.initials: BM
authors.lastname: Hendriks
authors.affiliation: 1 Departments of Radiology, Maastricht University Medical Center, Maastricht, Netherlands.|2 CARIM School for Cardiovascular Diseases, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Madeleine
authors.initials: M
authors.lastname: Kok
authors.affiliation: 1 Departments of Radiology, Maastricht University Medical Center, Maastricht, Netherlands.|2 CARIM School for Cardiovascular Diseases, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Casper
authors.initials: C
authors.lastname: Mihl
authors.affiliation: 2 CARIM School for Cardiovascular Diseases, Maastricht University Medical Center, Maastricht, Netherlands.|3 Departments of Cardiology, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Sebastiaan C A M
authors.initials: SC
authors.lastname: Bekkers
authors.affiliation: 1 Departments of Radiology, Maastricht University Medical Center, Maastricht, Netherlands.|2 CARIM School for Cardiovascular Diseases, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Joachim E
authors.initials: JE
authors.lastname: Wildberger
authors.affiliation: 1 Departments of Radiology, Maastricht University Medical Center, Maastricht, Netherlands.|2 CARIM School for Cardiovascular Diseases, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Marco
authors.initials: M
authors.lastname: Das
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000000981:diagnostic imaging*; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D003287:Contrast Media