title: Feasibility and accuracy of fusion imaging during thoracic endovascular aortic repair.
abstract: OBJECTIVE
  To evaluate accuracy and feasibility of fusion imaging during thoracic endovascular aortic repair (TEVAR).
  
  
  METHODS
  From January 2013 to January 2015 fusion imaging was used in 18 TEVAR procedures. Patients were prospectively enrolled for the survey and informed consent was obtained. Planning of the procedure and computed tomography (CT) angiography (CTA) segmentation with determination of all relevant surgical landmarks that should be displayed on fusion imaging was done using the preoperative CTA data. The registration was done with an intraoperative noncontrast-enhanced cone beam CT and CTA (three-dimensional [3D]-3D registration; n = 15) or with two fluoroscopic images in anteroposterior and lateral projection and the CTA (two-dimensional-3D registration; n = 3). An intraoperative digital subtraction angiography was performed to adjust fusion imaging and to allow accuracy measurement.
  
  
  RESULTS
  Fusion imaging was possible in all included patients. The median dose for noncontrast-enhanced cone beam CT imaging was 28.6 Gy/cm(2) (range, 17.9-43.3) and 0.46 Gy cm(2) for two fluoroscopic images in the two-dimensional-3D group. Full accuracy was achieved in two cases (11%), with a median deviation of 11.7 mm (range, 0.0-37.2). Manual realignment was possible in all cases.
  
  
  CONCLUSIONS
  This early experience shows that fusion imaging is feasible in TEVAR procedures using different registration methods. However, it shows a significant deviation in thoracic procedures because of different sources of error, making confirmation of fusion overlay with a digital subtraction angiography necessary in any case.
authors.affiliation: Department of Vascular and Endovascular Surgery at the University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Christof Johannes
authors.initials: CJ
authors.lastname: Schulz
authors.affiliation: Department of Vascular and Endovascular Surgery at the University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schmitt
authors.affiliation: Department of Vascular and Endovascular Surgery at the University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Dittmar
authors.initials: D
authors.lastname: Böckler
authors.affiliation: Department of Vascular and Endovascular Surgery at the University Hospital Heidelberg, Heidelberg, Germany. Electronic address: Philipp.Geisbuesch@med.uni-heidelberg.de.
authors.forename: Philipp
authors.initials: P
authors.lastname: Geisbüsch
mesh_terms: D059925:Anatomic Landmarks; D015901:Angiography, Digital Subtraction; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000601:surgery*; D001027:Aortography / Q000379:methods*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D061330:Multidetector Computed Tomography; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011474:Prosthesis Design; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015607:Stents; D016896:Treatment Outcome; D057188:Workflow