MR-Guided Kernel EM Reconstruction for Reduced Dose PET Imaging.
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ABSTRACT:
SUBMITTER: Bland J
PROVIDER: S-EPMC6027990 | biostudies-other | 2018 May
REPOSITORIES: biostudies-other
Publications
MR-Guided Kernel EM Reconstruction for Reduced Dose PET Imaging.
Bland James J Mehranian Abolfazl A Belzunce Martin A MA Ellis Sam S McGinnity Colm J CJ Hammers Alexander A Reader Andrew J AJ
IEEE transactions on radiation and plasma medical sciences 20171109 3
PET image reconstruction is highly susceptible to the impact of Poisson noise, and if shorter acquisition times or reduced injected doses are used, the noisy PET data become even more limiting. The recent development of kernel expectation maximisation (KEM) is a simple way to reduce noise in PET images, and we show in this work that impressive dose reduction can be achieved when the kernel method is used with MR-derived kernels. The kernel method is shown to surpass maximum likelihood expectatio ...[more]
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Project description:Imaging-based techniques have enabled the direct integration of noninvasive imaging with minimally invasive interventions such as photothermal therapy (PTT) to improve the precision of treatment.MethodsWe investigated the feasibility of PTT for ovarian cancer under the guidance of PET and MR temperature imaging using copper sulfide nanoparticles (CuS NPs). The tumor distribution of the CuS NPs after systemic administration was assessed using highly sensitive, quantifiable PET imaging. Two wavelengths of near-infrared (NIR) lasers-808 and 980 nm-were tested for PTT using noninvasive MR temperature imaging real-time monitoring.ResultsThe in vivo studies revealed that the 980-nm NIR laser had better photothermal effects than the 808-nm NIR laser. These results were in accord with the histologic findings. In vivo PTT using CuS NPs combined with 980-nm laser irradiation achieved significant tumor ablation compared with no treatment control in both subcutaneous (P = 0.007) and orthotopic (P < 0.001) models of ovarian cancer with regard to the percentage of necrotic damage.ConclusionOur results indicate that real-time monitoring of the accuracy of PTT is a promising approach for future clinical translation of this emerging thermal ablation technique.
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