We describe a theoretical framework for reversibly modulating 4D light fields with patterned masks in the optical path of a lens based camera. Based on this framework, we present a novel design to reconstruct the 4D light field from a 2D camera image without any additional lenses as required by previous light field cameras. The patterned mask attenuates light rays inside the camera instead of b...

introduction: ordered subset expectation maximization (osem), is an effective iterative method for spect image reconstruction. the aim of this study is the evaluation of the role of system matrix in osem image reconstruction method using four different physical beam radiation models with three detection configurations. methods: spect was done with an arc of 180 degree in 32 projections after i...

  Introduction: Ordered subset expectation maximization (OSEM), is an effective iterative method for SPECT image reconstruction. The aim of this study is the evaluation of the role of system matrix in OSEM image reconstruction method using four different physical beam radiation models with three detection configurations. Methods: SPECT was done with an arc of 180 deg...

A method for motion compensated iterative CT reconstruction of a cardiac region-of-interest is presented. The algorithm is an ordered subset maximum likelihood approach with spherically symmetric basis functions, and it uses an ECG for gating. Since the straightforward application of iterative methods to CT data has the drawback that a field-of-view has to be reconstructed, which covers the com...

Gated cardiac SPECT imaging has been widely used in the evaluation of cardiac functions. The acquired fourdimensional (4D) sinogram data have both inter-frame correlation among the time sequence and intra-frame correlation within each 3D frame. The unique features of Karhune-Loève (KL) transform for de-correlating the data sequence for noise reduction, feature extraction, etc, have been well re...

Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue (4D PAT). A particular example is the planar Fabry-Pérot (FP) photoacoustic scanner, which yields high-resolution 3D images but takes several m...

OBJECTIVE To study the feasibility and the potential benefits of defining the internal gross tumor volume (IGTV) of hepatocellular carcinoma (HCC) using contrast-enhanced 4D CT images obtained by combining arterial-phase (AP) contrast-enhanced (CE) 3D CT and non-contrast-enhanced (NCE) 4D CT images using deformable registration (DR). METHODS Ten HCC patients who had received radiotherapy befo...

We introduce a new method of rotational image acquisition for four-dimensional (4D) optical coherence tomography (OCT) of beating embryonic chick hearts. The rotational axis and the central A-scan of the OCT are identical. An out-of-phase image sequence covering multiple heartbeats is acquired at every angle of an incremental rotation of the deflection mirrors of the OCT system. Image acquisiti...

BACKGROUND Confocal laser scanning microscope (CLSM) has been widely employed in our laboratory for structural and functional analysis of clinical dental specimens and live cell imaging of cultured oral epithelial cells. METHODS In this vitro study, a Fluoview 1000 (Olympus) confocal system was utilised to study thick sections of carious lesions (40-100 μm) and periodontal disease tissue samp...