title: Multidetector computed tomographic characteristics of nonabsorbable polymer versus titanium ligature clips in a vascular model.
abstract: OBJECTIVE
  Multidetector cardiac computed tomography is commonly performed to evaluate coronary bypass grafts, but titanium clips result in significant image artifact. Multidetector cardiac computed tomographic characteristics of newly developed nonabsorbable polymer clips are unknown. This study was undertaken to compare the image characteristics of polymer clips and titanium clips applied to a vascular model.
  
  
  METHODS
  A vascular model was created with two porcine internal thoracic arteries. Branches were ligated with 5 titanium clips on one vessel and 6 polymer clips on the other. Vessels were imaged under pressure with normal saline solution in a 16-detector computed tomographic scanner. Image intensity was quantified in absolute Hounsfield units for clips and adjacent lumen and then normalized to the average lumen intensity.
  
  
  RESULTS
  No difference in absolute intensity was found between polymer clips and adjacent lumen (polymer clip 1021.2 +/- 19.0 absolute Hounsfield units, adjacent lumen 1001.7 +/- 15.7 absolute Hounsfield units, P = .095). A statistically significant difference was noted between titanium clips and adjacent lumen (titanium clips 3408.8 +/- 177.3 absolute Hounsfield units, adjacent lumen 1072.7 +/- 52.1 absolute Hounsfield units, P < .0001). A statistically significant difference was also noted between titanium and polymer clips (P < .0001).
  
  
  CONCLUSIONS
  The use of polymer clips in coronary bypass grafts should result in significantly improved multidetector cardiac computed tomographic image quality.
authors.affiliation: Loma Linda University School of Medicine, and VA Loma Linda Health Care System, Loma Linda, Calif 92357, USA. Gary.Foster2@va.gov
authors.forename: Gary
authors.initials: G
authors.lastname: Foster
authors.forename: Michael
authors.initials: M
authors.lastname: Plunkett
authors.forename: Aaron
authors.initials: A
authors.lastname: Wagner
authors.forename: Selwin
authors.initials: S
authors.lastname: Abraham
authors.forename: Duane
authors.initials: D
authors.lastname: Baldwin
authors.forename: Bryan
authors.initials: B
authors.lastname: Hill
authors.forename: Hannah
authors.initials: H
authors.lastname: Kim
mesh_terms: D000818:Animals; D016477:Artifacts; D001026:Coronary Artery Bypass / Q000295:instrumentation*; D006321:Heart / Q000000981:diagnostic imaging; D008954:Models, Biological; D011108:Polymers; D013525:Surgical Instruments; D013552:Swine; D014025:Titanium; D014057:Tomography, X-Ray Computed
chemical_list: D011108:Polymers; D014025:Titanium