Publications by authors named "H J Halpern"

Background And Objective: Optimization based image reconstruction algorithm is an advanced algorithm in medical imaging. However, the corresponding solving algorithm is challenging because the model is usually large-scale and non-smooth. This work aims to devise a simple and convergent solver for optimization model.

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We report the development of a high-sensitivity and high-resolution PET subsystem for a next-generation preclinical PET/EPR hybrid scanner for investigating and improving hypoxia imaging with PET. The PET subsystem consists of 14 detector modules (DM) installed within a cylindrical supporting frame whose outer and inner diameters are 115mm and 60mm, respectively. Each DM contains eight detector units (DU) in a row and each DU is made of a 12×12 array of 1×1×10mm LYSO crystals (with a 1.

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Electron paramagnetic resonance (EPR) imaging is an advanced in vivo oxygen imaging modality. The main drawback of EPR imaging is the long scanning time. Sparse-view projections collection is an effective fast scanning pattern.

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Molecular oxygen and its thermodynamic transformation drive nearly all life processes. Quantitative measurement and imaging of oxygen in living systems is of fundamental importance for the study of life processes and their aberrations-disease- many of which are affected by hypoxia, or low levels of oxygen. Cancer is among the disease processes profoundly affected by hypoxia.

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Article Synopsis
  • The study focuses on improving continuous-wave electron paramagnetic resonance imaging (CW EPRI) by developing algorithms that reconstruct high-quality four-dimensional spectral-spatial (4DSS) images from sparsely sampled data, rather than the usual densely sampled views.* -
  • Traditional reconstruction methods like filtered-backprojection (FBP) require a lot of scan time, prompting the need for faster data collection methods that still achieve accurate imaging results.* -
  • Through numerical tests with both simulated and actual data, the new optimization-based algorithms demonstrated significant improvements in image quality and physical-parameter estimation, making them a promising alternative for quicker CW EPRI scanning.*
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