title: Use of C-Arm Cone Beam CT During Hepatic Radioembolization: Protocol Optimization for Extrahepatic Shunting and Parenchymal Enhancement.
abstract: OBJECTIVE
  To optimize a C-arm computed tomography (CT) protocol for radioembolization (RE), specifically for extrahepatic shunting and parenchymal enhancement.
  
  
  METHODS
  A prospective development study was performed per IDEAL recommendations. A literature-based protocol was applied in patients with unresectable and chemorefractory liver malignancies undergoing an angiography before radioembolization. Contrast and scan settings were adjusted stepwise and repeatedly reviewed in a consensus meeting. Afterwards, two independent raters analyzed all scans. A third rater evaluated the SPECT/CT scans as a reference standard for extrahepatic shunting and lack of target segment perfusion.
  
  
  RESULTS
  Fifty scans were obtained in 29 procedures. The first protocol, using a 6 s delay and 10 s scan, showed insufficient parenchymal enhancement. In the second protocol, the delay was determined by timing parenchymal enhancement on DSA power injection (median 8 s, range 4-10 s): enhancement improved, but breathing artifacts increased (from 0 to 27 %). Since the third protocol with a 5 s scan decremented subjective image quality, the second protocol was deemed optimal. Median CNR (range) was 1.7 (0.6-3.2), 2.2 (-1.4-4.0), and 2.1 (-0.3-3.0) for protocol 1, 2, and 3 (p = 0.80). Delineation of perfused segments was possible in 57, 73, and 44 % of scans (p = 0.13). In all C-arm CTs combined, the negative predictive value was 95 % for extrahepatic shunting and 83 % for lack of target segment perfusion.
  
  
  CONCLUSIONS
  An optimized C-arm CT protocol was developed that can be used to detect extrahepatic shunts and non-perfusion of target segments during RE.
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands. a.f.vandenhoven@umcutrecht.nl.
authors.forename: Andor F
authors.initials: AF
authors.lastname: van den Hoven
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Jip F
authors.initials: JF
authors.lastname: Prince
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Bart
authors.initials: B
authors.lastname: de Keizer
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Evert-Jan P A
authors.initials: EJ
authors.lastname: Vonken
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Rutger C G
authors.initials: RC
authors.lastname: Bruijnen
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Helena M
authors.initials: HM
authors.lastname: Verkooijen
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Marnix G E H
authors.initials: MG
authors.lastname: Lam
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E.01.132, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Maurice A A J
authors.initials: MA
authors.lastname: van den Bosch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003097:Collateral Circulation; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D003287:Contrast Media; D005260:Female; D006801:Humans; D008099:Liver / Q000098:blood supply / Q000000981:diagnostic imaging; D008102:Liver Circulation; D008113:Liver Neoplasms / Q000098:blood supply* / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011856:Radiographic Image Enhancement; D019275:Radiopharmaceuticals / Q000008:administration & dosage*; D012039:Regional Blood Flow; D013668:Technetium Tc 99m Aggregated Albumin / Q000008:administration & dosage; D014283:Triiodobenzoic Acids
chemical_list: D003287:Contrast Media; D019275:Radiopharmaceuticals; D013668:Technetium Tc 99m Aggregated Albumin; D014283:Triiodobenzoic Acids; C044834:iodixanol
keywords: C-arm CT; Cone beam CT; IDEAL; Protocol optimization; Radioembolization