title: C-arm flat-panel CT arthrography of the shoulder: Radiation dose considerations and preliminary data on diagnostic performance.
abstract: OBJECTIVE
  To investigate radiation dose and diagnostic performance of C-arm flat-panel CT (FPCT) versus standard multi-detector CT (MDCT) shoulder arthrography using MRI-arthrography as reference standard.
  
  
  METHODS
  Radiation dose of two different FPCT acquisitions (5 and 20 s) and standard MDCT of the shoulder were assessed using phantoms and thermoluminescence dosimetry. FPCT arthrographies were performed in 34 patients (mean age 44 ± 15 years). Different joint structures were quantitatively and qualitatively assessed by two independent radiologists. Inter-reader agreement and diagnostic performance were calculated.
  
  
  RESULTS
  Effective radiation dose was markedly lower in FPCT 5 s (0.6 mSv) compared to MDCT (1.7 mSv) and FPCT 20 s (3.4 mSv). Contrast-to-noise ratios (CNRs) were significantly (p < 0.05) higher in FPCT 20-s versus 5-s protocols. Inter-reader agreements of qualitative ratings ranged between к = 0.47-1.0. Sensitivities for cartilage and rotator cuff pathologies were low for FPCT 5-s (40 % and 20 %) and moderate for FPCT 20-s protocols (75 % and 73 %). FPCT showed high sensitivity (81-86 % and 89-99 %) for bone and acromioclavicular-joint pathologies.
  
  
  CONCLUSIONS
  Using a 5-s protocol FPCT shoulder arthrography provides lower radiation dose compared to MDCT but poor sensitivity for cartilage and rotator cuff pathologies. FPCT 20-s protocol is moderately sensitive for cartilage and rotator cuff tendon pathology with markedly higher radiation dose compared to MDCT.
  
  
  CONCLUSIONS
  • FPCT shoulder arthrography is feasible with fluoroscopy and CT in one workflow. • A 5-s FPCT protocol applies a lower radiation dose than MDCT. • A 20-s FPCT protocol is moderately sensitive for cartilage and tendon pathology.
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Rämistrasse 100, 8091, Zürich, Switzerland. Roman.Guggenberger@usz.ch.
authors.forename: Roman
authors.initials: R
authors.lastname: Guggenberger
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Rämistrasse 100, 8091, Zürich, Switzerland.
authors.forename: Erika J
authors.initials: EJ
authors.lastname: Ulbrich
authors.affiliation: Department of Radiology, Balgrist University Hospital, Zurich, Switzerland.
authors.forename: Tobias J
authors.initials: TJ
authors.lastname: Dietrich
authors.affiliation: Siemens Healthcare GmbH, Business Area Advanced Therapies, Forchheim, Germany.
authors.forename: Rosemarie
authors.initials: R
authors.lastname: Scholz
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Rämistrasse 100, 8091, Zürich, Switzerland.
authors.forename: Pascal
authors.initials: P
authors.lastname: Kaelin
authors.affiliation: Siemens Healthcare GmbH, Business Area Advanced Therapies, Forchheim, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Köhler
authors.affiliation: Siemens Healthcare GmbH, Business Area Advanced Therapies, Forchheim, Germany.
authors.forename: Thilo
authors.initials: T
authors.lastname: Elsässer
authors.affiliation: Aix-Marseille Université, CNRS, ISM UMR 7287, Marseille, France.|Radiology Department, APHM, Marseille, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Le Corroller
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Rämistrasse 100, 8091, Zürich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pfammatter
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Rämistrasse 100, 8091, Zürich, Switzerland.
authors.forename: Hatem
authors.initials: H
authors.lastname: Alkadhi
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Rämistrasse 100, 8091, Zürich, Switzerland.
authors.forename: Gustav
authors.initials: G
authors.lastname: Andreisek
mesh_terms: D000328:Adult; D000368:Aged; D001175:Arthrography / Q000295:instrumentation*; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D019047:Phantoms, Imaging; D011446:Prospective Studies; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012785:Shoulder Joint / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000592:standards
keywords: Arthrography; C-arm cone-beam CT; Computed tomography; Radiation dose; Shoulder