Optimized preoperative planning of double outlet right ventricle patients by 3D printing and virtual reality: a pilot study

Abstract

Objectives: In complex double outlet right ventricle (DORV) patients, the optimal surgical approach may be difficult to assess based on conventional 2-dimensional (2D) ultrasound (US) and computed tomography (CT) imaging. The aim of this study is to assess the added value of 3-dimensional (3D) printed and 3D virtual reality (3D-VR) models of the heart used for surgical planning in DORV patients, supplementary to the gold standard 2D imaging modalities.

Methods: Five patients with different DORV subtypes and high-quality CT scans were selected retrospectively. 3D prints and 3D-VR models were created. Twelve congenital cardiac surgeons and paediatric cardiologists, from 3 different hospitals, were shown 2D-CT first, after which they assessed the 3D print and 3D-VR models in random order. After each imaging method, a questionnaire was filled in on the visibility of essential structures and the surgical plan.

Results: Spatial relationships were generally better visualized using 3D methods (3D printing/3D-VR) than in 2D. The feasibility of ventricular septum defect patch closure could be determined best using 3D-VR reconstructions (3D-VR 92%, 3D print 66% and US/CT 46%, P < 0.01). The percentage of proposed surgical plans corresponding to the performed surgical approach was 66% for plans based on US/CT, 78% for plans based on 3D printing and 80% for plans based on 3D-VR visualization.

Conclusions: This study shows that both 3D printing and 3D-VR have additional value for cardiac surgeons and cardiologists over 2D imaging, because of better visualization of spatial relationships. As a result, the proposed surgical plans based on the 3D visualizations matched the actual performed surgery to a greater extent.

Keywords: 3D printing; Congenital cardiac surgery; Congenital heart disease; Double outlet right ventricle; Surgical planning; Virtual reality.

Figure 1:

Imaging modalities used in double outlet right ventricle patients. (A) Ultrasound 4-chamber overview, (B) axial CT image, (C) anterior view of the 3D printed model, (D) lateral view of the 3D printed model, (E) right lateral view of the 3D-VR reconstruction, (F) anterior view of the 3D-VR reconstruction. Ao: aorta; LA: left atrium; LV: left ventricle; PA: pulmonary artery; RA: right atrium; RV: right ventricle; ^: coronary artery; *: ventricular septum defect.

Figure 2:

CT scan with segmentations of the cardiac structures. An axial (A), coronal (B) and sagittal (C) cross-sectional slice are shown, together with the highlighted cardiac segments. Ao: aorta; LA: left atrium; LV: left ventricle; PA: pulmonary artery; RA: right atrium; RV: right ventricle; ^: coronary artery; *: ventricular septum defect.

Figure 3:

Overview of the workflow; creating 3D models, performing experiments and outcomes.

Figure 4:

Participants’ opinion towards future use of 3D visualization.

Figure 5:

Visibility of the most important essential modifiers for surgical planning. Based on 2D ultrasound and computed tomography images (US/CT), 3D-Virtual Reality (3D-VR) and 3D printing. The P values are based on the likelihood ratio test, based on the linear mixed-effect model. *P<0.00111 of the post hoc analysis between the groups.

Figure 6:

Number of surgical plans corresponding to the actual performed procedure, based on ultrasound and CT images (conventional 2D imaging), 3D printed models, and the 3D-VR models (left to right).