title: Optimal scan timing and intravenous route for contrast-enhanced computed tomography in patients after Fontan operation.
abstract: OBJECTIVE
  To determine the optimal scan timing and adequate intravenous route for patients having undergone the Fontan operation.
  
  
  METHODS
  A total of 88 computed tomographic images in 49 consecutive patients who underwent the Fontan operation were retrospectively evaluated and divided into 7 groups: group 1, bolus-tracking method with either intravenous route (n = 20); group 2, 1-minute-delay scan with single antecubital route (n = 36); group 3, 1-minute-delay scan with both antecubital routes (n = 2); group 4, 1-minute-delay scan with foot vein route (n = 3); group 5, 1-minute-delay scan with simultaneous infusion via both antecubital and foot vein routes (n = 2); group 6, 3-minute-delay scan with single antecubital route (n = 22); and group 7, 3-minute-delay scan with foot vein route (n = 3). The presence of beam-hardening artifact, uniform enhancement, and optimal enhancement was evaluated at the right pulmonary artery (RPA), left pulmonary artery (LPA), and Fontan tract. Optimal enhancement was determined when evaluation of thrombus was possible. Standard deviation was measured at the RPA, LPA, and Fontan tract.
  
  
  RESULTS
  Beam-hardening artifacts of the RPA, LPA, and Fontan tract were frequently present in groups 1, 4, and 5. The success rate of uniform and optimal enhancement was highest (100%) in groups 6 and 7, followed by group 2 (75%). An SD of less than 30 Hounsfield unit for the pulmonary artery and Fontan tract was found in groups 3, 6, and 7.
  
  
  CONCLUSIONS
  The optimal enhancement of the pulmonary arteries and Fontan tract can be achieved by a 3-minute-delay scan irrespective of the intravenous route location.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Eun-Ah
authors.initials: EA
authors.lastname: Park
authors.forename: Whal
authors.initials: W
authors.lastname: Lee
authors.forename: Se-Young
authors.initials: SY
authors.lastname: Chung
authors.forename: Yong Hu
authors.initials: YH
authors.lastname: Yin
authors.forename: Jin Wook
authors.initials: JW
authors.lastname: Chung
authors.forename: Jae Hyung
authors.initials: JH
authors.lastname: Park
mesh_terms: D000293:Adolescent; D000328:Adult; D016477:Artifacts; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media; D005260:Female; D018729:Fontan Procedure; D006801:Humans; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D007472:Iohexol / Q000031:analogs & derivatives; D015588:Observer Variation; D011183:Postoperative Complications / Q000000981:diagnostic imaging; D011651:Pulmonary Artery / Q000000981:diagnostic imaging*; D011856:Radiographic Image Enhancement / Q000379:methods*; D012189:Retrospective Studies; D013927:Thrombosis / Q000000981:diagnostic imaging*; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide