title: Imaging guidance with C-arm CT: prospective evaluation of its impact on patient radiation exposure during transhepatic arterial chemoembolization.
abstract: OBJECTIVE
  To prospectively evaluate the impact of C-arm CT on radiation exposure to hepatocellular carcinoma (HCC) patients treated by chemoembolization.
  
  
  METHODS
  Patients with HCC (N = 87) underwent digital subtraction angiography (DSA; control group) or combined C-arm CT/DSA (test group) for chemoembolization. Dose-area product (DAP) and cumulative dose (CD) were measured for guidance and treatment verification. Contrast agent volume and C-arm CT utility were also measured.
  
  
  RESULTS
  The marginal DAP increase in the test group was offset by a substantial (50%) decrease in CD from DSA. Use of C-arm CT allowed reduction of DAP and CD from DSA imaging (P = .007 and P = .017). Experienced operators were more efficient in substituting C-arm CT for DSA, resulting in a negligible increase (7.5%) in total DAP for guidance, compared with an increase of 34% for all operators (P = .03). For treatment verification, DAP from C-arm CT exceeded that from DSA, approaching that of conventional CT. The test group used less contrast medium (P = .001), and C-arm CT provided critical or supplemental information in 20% and 17% of patients, respectively.
  
  
  CONCLUSIONS
  Routine use of C-arm CT can increase stochastic risk (DAP) but decrease deterministic risk (CD) from DSA. However, the increase in DAP is operator-dependent, thus, with experience, it can be reduced to under 10%. C-arm CT provides information not provided by DSA in 33% of patients, while decreasing the use of iodinated contrast medium. As with all radiation-emitting modalities, C-arm CT should be used judiciously.
authors.affiliation: Division of Interventional Radiology, H-3652, Stanford University Medical Center, Stanford, CA 94305-5642, USA. kothary@stanford.edu
authors.forename: Nishita
authors.initials: N
authors.lastname: Kothary
authors.forename: Mohamed H K
authors.initials: MH
authors.lastname: Abdelmaksoud
authors.forename: Alessia
authors.initials: A
authors.lastname: Tognolini
authors.forename: Rebecca
authors.initials: R
authors.lastname: Fahrig
authors.forename: Jarrett
authors.initials: J
authors.lastname: Rosenberg
authors.forename: David M
authors.initials: DM
authors.lastname: Hovsepian
authors.forename: Arundhuti
authors.initials: A
authors.lastname: Ganguly
authors.forename: John D
authors.initials: JD
authors.lastname: Louie
authors.forename: William T
authors.initials: WT
authors.lastname: Kuo
authors.forename: Gloria L
authors.initials: GL
authors.lastname: Hwang
authors.forename: Alison
authors.initials: A
authors.lastname: Holzer
authors.forename: Daniel Y
authors.initials: DY
authors.lastname: Sze
authors.forename: Lawrence V
authors.initials: LV
authors.lastname: Hofmann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D002140:California; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D016461:Chemoembolization, Therapeutic; D003287:Contrast Media; D005260:Female; D006499:Hepatic Artery / Q000000981:diagnostic imaging*; D006801:Humans; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D061214:Patient Safety; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000209:etiology / Q000517:prevention & control; D015641:Radiography, Interventional / Q000009:adverse effects / Q000379:methods*; D012044:Regression Analysis; D018570:Risk Assessment; D012307:Risk Factors; D014057:Tomography, X-Ray Computed / Q000009:adverse effects
chemical_list: D003287:Contrast Media