Amelie Kugler, Torsten Kuwert, Philipp Ritt, Andreas Grings
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引用次数: 0
Abstract
Aim: Implanted metal prostheses can cause severe artifacts in reconstructed computed tomography (CT) images. To reduce the diagnostic impact of these artifacts and improve attenuation correction in single photon emission computed tomography (SPECT), an algorithm of iterative metal artifact reduction (iMAR) for SPECT/CT systems was developed. The aims of this study were (a) to assess the difference in visual image quality by comparing CT and SPECT images reconstructed with and without iMAR and (b) to determine the influence of iMAR on quantitative 99mTc-uptake in SPECT/CT.
Methods: This retrospective study includes 21 patients with implanted metal prostheses who underwent SPECT/CT bone scintigraphy. CT data were reconstructed with iMAR and without (noMAR) and were used for attenuation correction of SPECT data for xSPECT Quant and xSPECT Bone reconstruction. The effect of iMAR on image quality was evaluated by visual analysis and the effect on quantitative SPECT/CT was assessed by measuring HU values and absolute uptake values (kBq/mL) in volumes of interest (VOIs).
Results: There was a significant reduction of visible metal artifacts with iMAR (p<0.01) in the CT images, but visual differences in the SPECT images were minor. The values of quantitative tracer uptake in VOIs near metal implants were lower for iMAR vs. noMAR xSPECT Quant (p<0.01). Only VOIs near metal showed significant differences in HU values, which were 14.6% lower for iMAR CT (p<0.01).
Conclusion: The use of iMAR reduces metal artifacts in CT and improves the perceived image quality. Although in some cases a significant difference in the quantitative evaluation of SPECT/CT was observed, the influence of iMAR can be considered small in relation to other factors in the clinical setting.
期刊介绍:
Als Standes- und Fachorgan (Organ von Deutscher Gesellschaft für Nuklearmedizin (DGN), Österreichischer Gesellschaft für Nuklearmedizin und Molekulare Bildgebung (ÖGN), Schweizerischer Gesellschaft für Nuklearmedizin (SGNM, SSNM)) von hohem wissenschaftlichen Anspruch befasst sich die CME-zertifizierte Nuklearmedizin/ NuclearMedicine mit Diagnostik und Therapie in der Nuklearmedizin und dem Strahlenschutz: Originalien, Übersichtsarbeiten, Referate und Kongressberichte stellen aktuelle Themen der Diagnose und Therapie dar.
Ausführliche Berichte aus den DGN-Arbeitskreisen, Nachrichten aus Forschung und Industrie sowie Beschreibungen innovativer technischer Geräte, Einrichtungen und Systeme runden das Konzept ab.
Die Abstracts der Jahrestagungen dreier europäischer Fachgesellschaften sind Bestandteil der Kongressausgaben.
Nuklearmedizin erscheint regelmäßig mit sechs Ausgaben pro Jahr und richtet sich vor allem an Nuklearmediziner, Radiologen, Strahlentherapeuten, Medizinphysiker und Radiopharmazeuten.