title: A transoesophageal echocardiographic image acquisition protocol for wide-view fusion of three-dimensional datasets to support atrial fibrillation catheter ablation.
abstract: OBJECTIVE
  The aim of this paper is to propose a transoesophageal echocardiography (TOE) image acquisition protocol which provides a systematic manner of acquiring a minimal number of overlapping 3D TOE datasets allowing the reconstruction of a wide 3D view of the left atrium (LA) with anatomical landmarks that are important for atrial fibrillation catheter ablation.
  
  
  METHODS
  In eight cardiac surgical patients, 3D TOE datasets were acquired with a six-step protocol. In the protocol, step 1 aims to acquire the central view of the mitral valve (MV), aortic valve (AV) and left atrial appendage (LAA). Step 2 was developed to acquire the left pulmonary veins (PVs) and step 3 to acquire the right PVs. Steps 4, 5 and 6 were developed to create a sufficient overlap between different datasets. 3D TOE datasets were registered and fused manually in end diastole.
  
  
  RESULTS
  The image acquisition protocol was feasible in all patients. In the fused 3D dataset, a wide 3D view of the LA is shown, and left and right PVs could be seen simultaneously. The LAA, MV, AV and fossa ovalis (FO) were visualised clearly in the 3D TOE datasets. The PV ostia, which are located at the edges of the 3D datasets, suffered more from the artefact of echo loss. The volume overlaps between neighbouring TOE datasets were 50-75 %.
  
  
  CONCLUSIONS
  The major part of the LA anatomy incorporating the PVs, LAA, MV, AV and FO as important anatomical landmarks can be reconstructed by registering and fusing 3D datasets acquired with the six-step TOE image acquisition protocol.
authors.affiliation: Department of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, the Netherlands.
authors.forename: Ben
authors.initials: B
authors.lastname: Ren
authors.forename: Harriët W
authors.initials: HW
authors.lastname: Mulder
authors.forename: Alexander
authors.initials: A
authors.lastname: Haak
authors.forename: Marijn
authors.initials: M
authors.lastname: van Stralen
authors.forename: Tamas
authors.initials: T
authors.lastname: Szili-Torok
authors.forename: Josien P W
authors.initials: JP
authors.lastname: Pluim
authors.forename: Marcel L
authors.initials: ML
authors.lastname: Geleijnse
authors.forename: Johan G
authors.initials: JG
authors.lastname: Bosch
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D017548:Echocardiography, Transesophageal / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome