Accuracy of semi-automated versus manual localisation of liver tumours in CT-guided ablation procedures

Objectives: To compare the accuracy of liver tumour localisation in intraprocedural computed tomography (CT) images of computer-based rigid registration or non-rigid registration versus mental registration performed by interventional radiologists. Methods: Retrospectively (2009-2017), 35 contrast-enhanced CT (CECT) images incorporating 56 tumours, acquired during CT-guided ablation procedures and their corresponding pre-procedural diagnostic CECTs were retrieved from the picture archiving and communication system (PACS). The original intraprocedural CECTs were de-enhanced to create a virtually unenhanced CT image (VUCT). Alignment of diagnostic CECTs to their corresponding intraprocedural VUCTs was performed with non-rigid or rigid registration. Mental registration was performed by four interventional radiologists. The original intraprocedural CECT served as the reference standard. Accuracy of tumour localisation was assessed with the target registration error (TRE). Statistical differences were analysed with the Wilcoxon sig

Alginate-lanthanide microspheres for MRI-guided embolotherapy

<p>In cancer therapy, a promising treatment option to accomplish a high tumor-to-normal-tissue ratio is endovascular intervention with microsized particles, such as embolotherapy. In this study, alginate microspheres (ams) were prepared with the JetCutter technique, which is based on cutting a sodium alginate solution jet stream into small droplets of uniform size which are then cross-linked with different lanthanides or iron-III, resulting in microspheres of a predefined size which can be visualized by magnetic resonance imaging (MRI). The microspheres were investigated for their size and morphology (light microscopy and scanning electron microscopy analysis), cation content and MRI properties. The lanthanide-ams formulations, with a uniform size of 250 mu m and a cation content between 0.72-0.94%, showed promising results for MR imaging. This was further demonstrated for Ho3+-cross-linked alginate microspheres (Ho3+-ams), the most potent microsphere formulation with respect to MR visualization, allowing single sphere detection and detailed microsphere distribution examination. Intravascular infusion of Ho3+-ams by catherization of ex vivo rabbit and porcine liver tissue and assessment of the procedure with MRI clearly showed accumulation and subsequently embolization of the targeted vessels, allowing accurate monitoring of the microsphere biodistribution throughout the tissue. Therefore, the different alginate lanthanide microsphere formulations developed in this study show great potential for utilization as image-guided embolotherapy agents. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.</p>