title: Comprehensive low-dose imaging of carotid and coronary arteries with a single-injection dual-source CT angiography protocol.
abstract: OBJECTIVE
  To assess the feasibility of a fast single-bolus combined carotid and coronary computed tomography angiography (CTA) protocol in asymptomatic patients.
  
  
  METHODS
  Thirty-three consecutive patients (18 women and 15 men) with a median age of 61 ± 14 years old (range 37-87 years) with known or suspected atherosclerotic disease were enrolled in this prospective study. A single breath-hold, single biphasic injection protocol (50 ml at 3 ml/s, 50 ml at 5 ml/s, 50 ml saline flush at 5 ml/s) was used for combined CTA imaging of the supra-aortic (SAA) and coronary arteries (CA) on a 64-slice dual-source CT (DSCT) machine. Helical CTA acquisition of the SAA was followed by prospective electrocardiography (ECG)-triggered coronary CTA. Subjective (four-point scale) image quality and objective signal-to-noise (SNR) and contrast-to-noise (CNR) measurements were performed. Vascular disease was graded on a four-point scale (grade 1: absent; grade 2: mild, grade 3: moderate; grade 4: severe). The radiation dose was recorded for each patient.
  
  
  RESULTS
  The average enhancement and subjective quality score of SAA and CA segments were 396 HU/358 HU and 1.2 ± 0.3/1.72 ± 0.4, respectively. The SNR was 27.1 ± 1.7 in the SAA and 21.6 ± 1.6 in the CA (p < 0.0001). The CNR was 18.1 ± 1.2 and 15.9 ± 1.8, respectively (p = 0.4). Four percent of SAA and 14% of CA segments (mostly due to peri-venous streak artefacts and small calibre, respectively) produced non-diagnostic images. SAA findings were as follows: 26/33 (79%) patients showed no disease and 6/33 (18%) had grade 2 and 1/33 (3%) had grade 3 disease. CA findings were as follows: 25/33 (76%) showed no disease and 6/33 (18%) patients had grade 2 and 2/33 (6%) had grade 3 disease. Five patients had disease in both districts. The average radiation dose for the combined CTA angiogram was 4.3 ± 0.6 mSv.
  
  
  CONCLUSIONS
  A fast, low-dose combined DSCT angiography protocol appears technically feasible for imaging carotid and coronary atherosclerotic disease.
authors.affiliation: Department of Radiological Sciences, David Geffen School of Medicine, Los Angeles, CA, USA. Electronic address: atognolini@outlook.com.
authors.forename: A
authors.initials: A
authors.lastname: Tognolini
authors.affiliation: Department of Radiological Sciences, David Geffen School of Medicine, Los Angeles, CA, USA.
authors.forename: C S
authors.initials: CS
authors.lastname: Arellano
authors.affiliation: Department of Radiological Sciences, School of Medicine, University of California, Irvine, CA, USA.
authors.forename: W
authors.initials: W
authors.lastname: Marfori
authors.affiliation: Department of Radiological Sciences, David Geffen School of Medicine, Los Angeles, CA, USA.
authors.forename: G
authors.initials: G
authors.lastname: Heidari
authors.affiliation: Department of Radiological Sciences, David Geffen School of Medicine, Los Angeles, CA, USA; Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, CA, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Sayre
authors.affiliation: Department of Radiological Sciences, School of Medicine, University of California, Irvine, CA, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Krishnam
authors.affiliation: Department of Radiological Sciences, David Geffen School of Medicine, Los Angeles, CA, USA.
authors.forename: S G
authors.initials: SG
authors.lastname: Ruehm
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods*; D055424:Cardiac-Gated Imaging Techniques; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging*; D003287:Contrast Media; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007479:Iopamidol; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D036542:Tomography, Spiral Computed
chemical_list: D003287:Contrast Media; D007479:Iopamidol