Magnetic resonance and computed tomography imaging fusion for live guidance of percutaneous pulmonary valve implantation

Figures

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  Figure 1. Step-by-step two-dimensional to threedimensional (2D–3D) registration of magnetic resonance imaging (MRI) and computed tomography (CT) datasets with utilization of angiography or internal markers as reference points

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  Figure 2. Percutaneous right ventricular outflow tract (RVOT) stenting and pulmonary valve implantation in 3-year-old male patient with pulmonary atresia (PA) and ventricular septal defect (VSD) with residual moderate stenosis and regurgitation of patch reconstructed RVOT. VesselNavigator assisted segmentation of magnetic resonance imaging 3D whole heart sequence without contrast (A). Green markers were placed to mark the right and left coronary artery (B). Additional yellow rings were placed to highlight the proximal, the narrowest and the distal part of the RVOT (C); origins of branch pulmonary arteries were marked with blue and the ascending aorta with a purple ring. Angiography and the position of two catheters placed in the aorta and the right atrium (yellow dotted line) were used for registration (D)

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  Figure 3. Live three-dimensional guidance of percutaneous pulmonary valve implantation. Magnetic resonance imaging derived three-dimensional roadmap (see Figure 2) was utilized to guide successive steps of the intervention: selective coronary artery angiography (A), pre-stenting with implantation of two covered stents (B), placement of a 26 mm Sapien 3 valve (Edwards) (C) and final angiography (D)

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  Figure 4. Fusion imaging with VesselNavigator for percutaneous pulmonary valve implantation (PPVI). Vessel-Navigator was used for planning, suitability testing and PPVI (A). Computed tomography (CT) and magnetic resonance imaging (MRI) datasets were used for two-dimensional to three-dimensional (2D–3D) registration (B)

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  Figure 5. Percutaneous pulmonary valve implantation in a patient with distal conduit and bilateral proximal pulmonary artery stenosis. Automatic three-dimensional (3D) reconstruction and multiplanar reformats from pre-registered computed tomography (CT) were manipulated to outline the conduit and the proximal pulmonary arteries (A). The stent landing zone was marked with one green ring, and the origin of the right and left pulmonary artery with another two blue rings (B). Pink rings indicate ostia of the right and left coronary artery. Bony structures were utilized to enhance manual 3D image fusion with stored fluoroscopy in two perpendicular projections (C). Movement of a soft catheter (black dotted line) within the borders of the 3D roadmap confirmed satisfactory initial alignment (D). Introduction of a stiff wire and balloon/stent assembly resulted in distortion of the anatomy (E) and significant mismatch of the 3D roadmap (F) and actual position of the graft and pulmonary arteries. The remainder of the procedure was successfully conducted with traditional two-dimensional guidance