relation: https://eprints.uet.vnu.edu.vn/eprints/id/eprint/3046/ title: Quantification of non-rigid liver deformation in radiofrequency ablation interventions using image registration creator: Luu Manh, Ha creator: Moelker, Adriaan creator: Klein, Stefan creator: Niessen, Wiro creator: Walsum, Theo van subject: Electronics and Computer Engineering subject: ISI-indexed journals description: Multi-modal image fusion for image guidance in minimally invasive liver interventions generally requires a registration of pre-operatively acquired images to interventional images of the patient. Whereas rigid registration approaches are fast and can be used in an interventional setting, the actual liver deformation may be non-rigid. The purpose of this paper is to assess the magnitude of non-rigid deformation of the liver between pre-operative and interventional CT images in case of tumor ablations, over the full liver and over parts of the liver that match the volumes typically imaged by a 3D ultrasound transducer. We acquired 3D abdominal CT scans of 38 patients that underwent radiofrequency ablation of liver tumors, pre-operative CT images as well as intra-operative CT images. To determine the magnitude of liver deformation due to pose changes and respiration, we non-rigidly registered the pre-operative CT scan to the intra-operative CT scan. By fitting this deformation to a rigid transformation in a region of interest and computing the residual displacements, the non-rigid deformation part can be quantified. We performed quantifications over the complete liver, as well as for two volumes of interest representative for sub-xiphoidal and inter-costal 3D ultrasound acquisitions. The results showed that a substantial amount of non-rigid deformation was found, and rotation of patient's pose and deep inhalation caused significant liver deformation. Hence we concluded that non-rigid motion correction in the interventions should be taken into account. publisher: IOP date: 2018-08-29 type: Article type: PeerReviewed identifier: Luu Manh, Ha and Moelker, Adriaan and Klein, Stefan and Niessen, Wiro and Walsum, Theo van (2018) Quantification of non-rigid liver deformation in radiofrequency ablation interventions using image registration. Physics in Medicine & Biology, 63 (17). ISSN 1361-6560 relation: http://iopscience.iop.org/journal/0031-9155 relation: 10.1088/1361-6560/aad706