본문 바로가기
HOME> 논문 > 논문 검색상세

논문 상세정보

NeuroImage v.162, 2017년, pp.276 - 288   SCI SCIE
본 등재정보는 저널의 등재정보를 참고하여 보여주는 베타서비스로 정확한 논문의 등재여부는 등재기관에 확인하시기 바랍니다.

MR-guided joint reconstruction of activity and attenuation in brain PET-MR

Mehranian, Abolfazl (Division of Imaging Sciences and Biomedical Engineering, Department of Biomedical Engineering, King's College London, St. Thomas' Hospital, London, UK ) ; Zaidi, Habib (Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva, Switzerland ) ; Reader, Andrew J. (Division of Imaging Sciences and Biomedical Engineering, Department of Biomedical Engineering, King's College London, St. Thomas' Hospital, London, UK ) ;
  • 초록  

    Abstract With the advent of time-of-flight (TOF) PET scanners, joint maximum-likelihood reconstruction of activity and attenuation (MLAA) maps has recently regained attention for the estimation of PET attenuation maps from emission data. However, the estimated attenuation and activity maps are scaled by unknown scaling factors. We recently demonstrated that in hybrid PET-MR, the scaling issue of this algorithm can be effectively addressed by imposing MR spatial constraints on the estimation of attenuation maps using a penalized MLAA (P-MLAA + ) algorithm. With the advent of simultaneous PET-MR systems, MRI-guided PET image reconstruction has also gained attention for improving the quantitative accuracy of PET images, usually degraded by noise and partial volume effects. The aim of this study is therefore to increase the benefits of MRI information for improving the quantitative accuracy of PET images by exploiting MRI-based anatomical penalty functions to guide the reconstruction of both activity and attenuation maps during their joint estimation. We employed an anato-functional joint entropy penalty function for the reconstruction of activity and an anatomical quadratic penalty function for the reconstruction of attenuation. The resulting algorithm was referred to as P-MLAA ++ since it exploits both activity and attenuation penalty functions. The performance of the P-MLAA algorithms were compared with MLAA and the widely used activity reconstruction algorithms such as maximum likelihood expectation maximization (MLEM) and penalized MLEM (P-MLEM) both corrected for attenuation using a conventional MRI segmentation-based attenuation correction (MRAC) method. The studied methods were evaluated using simulations and clinical studies taking the PET image reconstructed using reference CT-based attenuation maps as a reference. The simulation results showed that the proposed method can notably improve the visual quality of the PET images by reducing noise while preserving structural boundaries and at the same time improving the quantitative accuracy of the PET images. Our clinical reconstruction results showed that the MLEM-MRAC, P-MLEM-MRAC, MLAA, P-MLAA + and P-MLAA ++ algorithms result in, on average, quantification errors of −13.5 ± 3.1%, −13.4 ± 3.1%, −2.0 ± 6.5%, −3.0 ± 3.5% and −4.2 ± 3.6%, respectively, in different regions of the brain. In conclusion, whilst the P-MLAA + algorithm showed the best overall quantification performance, the proposed P-MLAA ++ algorithm provided simultaneous partial volume and attenuation corrections with only a minor compromise of PET quantification. Highlights An MR-guided joint activity and attenuation reconstruction method is presented to highlight the benefit of MRI in PET. Proposed algorithm was compared with conventional PET image reconstruction and attenuation correction methods. Our results showed that the proposed algorithm effectively reduces partial volume effects in PET images. It was demonstrated that this algorithm significantly improves the quantitative accuracy of PET images. Graphical abstract [DISPLAY OMISSION]


  • 주제어

    PET-MR .   Brain imaging .   Quantification .   Attenuation correction .   Segmentation.  

 활용도 분석

  • 상세보기

    amChart 영역
  • 원문보기

    amChart 영역

원문보기

무료다운로드
  • 원문이 없습니다.

유료 다운로드의 경우 해당 사이트의 정책에 따라 신규 회원가입, 로그인, 유료 구매 등이 필요할 수 있습니다. 해당 사이트에서 발생하는 귀하의 모든 정보활동은 NDSL의 서비스 정책과 무관합니다.

원문복사신청을 하시면, 일부 해외 인쇄학술지의 경우 외국학술지지원센터(FRIC)에서
무료 원문복사 서비스를 제공합니다.

NDSL에서는 해당 원문을 복사서비스하고 있습니다. 위의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.

이 논문과 함께 출판된 논문 + 더보기