Purpose: A recent clinical trial has demonstrated that noninvasive radioablation (NIRA) has the potential to reduce recurrent ventricular tachycardia (VT) that is refractory to drugs and standard catheter ablation. Electroanatomic mapping (EAM) that would be useful for planning is obtained during catheter ablation, but incompatibility between EAM and DICOM formats required for radiation planning has impeded the use of existing catheter-based mapping to guide NIRA and is an important hurdle for its wider adoption. In this paper we define a process to facilitate the fusion of catheter-based EAM with DICOM imaging for radiation planning.
Method and materials: The raw data export of the CARTO3 EAM system (version 6.0.45.171, ".mesh" file) was processed with a MATLAB script to generate 3-dimensional (3D) visual took kit files containing X, Y, Z coordinates obtained during mapping and corresponding impedance, voltage, and other point-based information. The image could then be visualized with standard image processing software (3D Slicer) and the target outlined on the image surface. This structure was in turn converted to a DICOM image and fused with patient thoracic imaging using anatomic landmarks. Robustness of the workflow was assessed through implementation with a second magnetic resonance imaging based VT ablation planning system, ADAS-VT.
Results: This process facilitated the fusion of EAM and DICOM imaging to inform selection of NIRA targets. The workflow was found to be robust and compatible with a second VT ablation planning system.
Conclusions: The conversion of catheter-based EAM to a DICOM compatible format permits the fusion of images for radiation planning and provides an avenue for the wider application of NIRA. Further improvements in the compatibility of these imaging formats would be expected to improve quality and reproducibility of image fusion.
Copyright © 2020 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.