As a breast-imaging technique, digital breast tomosynthesis has great potential to improve the diagnosis of early breast cancer over mammography. Ray-tracing-based reconstruction algorithms, such as ray-tracing back projection, maximum-likelihood expectation maximization (MLEM), ordered-subset MLEM (OS-MLEM), and simultaneous algebraic reconstruction technique (SART), have been developed as rec...

We compared reconstruction algorithms [filtered back projection (FBP), maximum likelihood expectation maximization (MLEM), and the simultaneous iterative reconstruction technique (SIRT)] in terms of the radiation dose and image quality, for exploring the possibility of decreasing the radiation dose during digital breast tomosynthesis (DBT). The three algorithms were implemented using a DBT syst...

At the experimental heavy ion tumor therapy facility at the GSI Darmstadt in-beam PET is operated. The in-beam PET data should be reconstructed as fast as possible (ideally, in real time), because they allow monitoring irregularities in beam delivery. To find a fast reconstruction algorithm with acceptable quality, MLEM [1] and OSEM [2] algorithms were compared for full-ring and dual-head geome...

Digital Breast Tomosynthesis (DBT) is a novel imaging technology to improve early breast cancer detection. It provides three-dimensional information of the breast to overcome the critical issues of overlapping anatomical structures of the breast. Among current available DBT reconstruction algorithms, Maximum Likelihood Expectation-Maximisation (MLEM) is a time-consuming iterative method to reco...

As an alternative to the use of traditional parallel hole collimators, SPECT imaging can be performed using rotating slat collimators. A gain in image quality could be expected from the higher photon collection efficiency, however, the plane integral data measured by this type of collimator require a reconstruction to invert the three-dimensional (3D) Radon transform. The use of iterative metho...

OBJECTIVE The threat of non-communicable diseases ("NCDs") is increasingly becoming a global health crisis and are pervasive in high, middle, and low-income populations resulting in an estimated 36 million deaths per year. There is a need to assess intellectual property rights ("IPRs") that may impede generic production and availability and affordability to essential NCD medicines. METHODS Us...

The efficient use of multicore architectures for sparse matrixvector multiplication (SpMV) is currently an open challenge. One algorithm which makes use of SpMV is the maximum likelihood expectation maximization (MLEM) algorithm. When using MLEM for positron emission tomography (PET) image reconstruction, one requires a particularly large matrix. We present a new storage scheme for this type of...

In this paper, distance driven (DD) backprojection image reconstruction was investigated for digital tomosysthesis. Digital tomosysthesis is an imaging technique to produce three dimensional information of the object with low radiation dosage. This paper is a new study of DD backprojection for image reconstruction in digital tomosysthesis. Since DD considers that the image pixel and detector ce...

BACKGROUND This article is based upon data gathered during a study conducted in partnership with the World Intellectual Property Organization on the patent status of products appearing on the World Health Organization's 2013 Model List of Essential Medicines (MLEM). It is a statistical analysis aimed at answering: in which developing countries are patents on essential medicines being filed? M...

Abstract We develop a positronium imaging method for the Jagiellonian PET (J-PET) scanners based on time-of-flight maximum likelihood expectation maximisation (TOF MLEM). The system matrix elements are calculated on-the-fly coincidences comprising two annihilation and one de-excitation photons that originate from ortho-positronium (o-Ps) decay. Using Geant4 library, Monte Carlo simulation was c...