title: Coronary arteries: assessment of image quality and optimal reconstruction window in retrospective ECG-gated multislice CT at 375-ms gantry rotation time.
abstract: Our objective was to evaluate the image quality of a 16-slice CT system with a rotation time of 375 ms in the assessment of coronary arteries. One hundred patients underwent iodine-enhanced CT coronary angiography within a single breath hold. Images were reconstructed in diastole, 300, 350, 400, 450, 500 and 550 ms prior to the onset of the next R-wave using absolute reverse retrospective ECG gating. The 15 coronary segments of the AHA classification were consensually reviewed by two radiologists. On the whole, best quality imaging was obtained with reconstruction intervals of -350 ms and -400 ms in high percentages of each segment (P<0.0001). Only 6.2% of the arteries with a diameter greater than or equal to 1.5 mm were not assessable because of extensive calcifications (3.9%), cardiac motion artifacts (1.9%), lack of enhancement (0.2%) and stent artifacts (0.3%). In patients with a heart rate above 70 beats per minute, the percentage of assessable segments decreased to 88%, while at a lower heart rate it increased to 95%. In 61% of the patients, all segments were assessable. In conclusion, this generation of CT technique may allow visualization of coronary arteries with a low percentage of non-assessable segments.
authors.affiliation: Department of Medical Imaging, Clinique Notre-dame, Avenue Delmée, 9, 7500, Tournai, Belgium. xavier.hamoir@skynet.be
authors.forename: Xavier L
authors.initials: XL
authors.lastname: Hamoir
authors.forename: Thomas
authors.initials: T
authors.lastname: Flohr
authors.forename: Vincent
authors.initials: V
authors.lastname: Hamoir
authors.forename: Laurent
authors.initials: L
authors.lastname: Labaki
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Tricquet
authors.forename: Alain
authors.initials: A
authors.lastname: Duhamel
authors.forename: Jacques
authors.initials: J
authors.lastname: Kirsch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D016477:Artifacts; D016009:Chi-Square Distribution; D003287:Contrast Media; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D003971:Diastole; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media