title: Effect of the reconstruction window obtained at the isovolumic relaxation period on the image quality in electrocardiographic-gated 16-multidetector-row computed tomography coronary angiography studies.
abstract: OBJECTIVE
  To evaluate whether images obtained during the reconstruction window responding to the isovolumic relaxation period could be used for rapid and easy postprocessing.
  
  
  METHODS
  One hundred ten consecutive patients with suspected coronary artery disease who had previously had a multidetector computed tomography (MDCT) scan for imaging coronary arteries were enrolled in this study. The age of the patients was 59 +/- 13 years (range: 33-78 years), and 77 (70%) were male. Multidetector computed tomography was performed on a 16-detector-row computed tomography scanner during 1 breath hold (16-24 seconds). Seven different sets of images reconstructed at every 10% of the R-R interval from 30% to 90% for contrast-enhanced scans at levels containing the first several centimeters of the left and right coronary arteries were analyzed. The best of these reconstruction windows were then compared with the images reconstructed at the isovolumic relaxation period, which is the last portion of the T wave at the end of the systole, where there is not any change in ventricular volume, which causes stepladder artifacts. The step artifact was classified as excellent, good, or poor. Image quality was assessed by 2 radiologists who were not aware of each other's interpretation.
  
  
  RESULTS
  According to the routinely used reconstructions, there were 76 patients with excellent image quality, 28 with good image quality, and 6 with poor image quality. For the period of isovolumic relaxation, there were 74 patients with excellent image quality, 25 with good image quality, and 11 with poor image quality.
  
  
  CONCLUSIONS
  If one begins image analysis with the isovolumic relaxation period reconstruction window, spending less time for postprocessing analyses, good image quality can be obtained such as with other good reconstruction windows.
authors.affiliation: Department of Radiology, Medical Faculty, Ataturk University, Erzurum, Turkey. akkanrad@hotmail.com
authors.forename: Mecit
authors.initials: M
authors.lastname: Kantarci
authors.forename: Naci
authors.initials: N
authors.lastname: Ceviz
authors.forename: Irmak
authors.initials: I
authors.lastname: Durur
authors.forename: Ummugulsum
authors.initials: U
authors.lastname: Bayraktutan
authors.forename: Adem
authors.initials: A
authors.lastname: Karaman
authors.forename: Fatih
authors.initials: F
authors.lastname: Alper
authors.forename: Omer
authors.initials: O
authors.lastname: Onbas
authors.forename: Adnan
authors.initials: A
authors.lastname: Okur
mesh_terms: D000328:Adult; D000368:Aged; D016477:Artifacts; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed