Due to low counts in an (111)In single photon emission computed tomography (SPECT) scan, a large part of the head was missing in the reconstructed images on Philips Extended Brilliance Workspace (EBW) and IntelliSpace Portal (ISP) workstations. This problem occurred for the ordered subsets expectation maximization (OSEM) algorithm with and without resolution recovery (Astonish), but not for fil...

Introduction: In nuclear medicine, the use of a pixelated semiconductor detector such as CZT is an of growing interest for introducing new devices. Especially, the spatial resolution can be improved by using a pixelated parallel-hole collimator with equal holes and pixel sizes based on the pixelated detector. The purpose of this study was to compare the effect of pixelated and ...

In conventional Compton camera systems, the image reconstruction is performed only in two-dimensional or three-dimensional spatial coordinates for a specific gamma-ray energy. By doing so, a priori knowledge of the incident gamma-ray energy is required, and usually an energy window is applied to select full energy deposition events. In some other applications, spectral-deconvolution algorithms ...

The reconstruction of dynamic PET data is usually performed using filtered backprojection algorithms (FBP). This method is fast, robust, linear and yields reliable quantitative results. However, the use of FBP for low count data, such as dynamic PET data, generally results in poor visual image quality, exhibiting high noise, disturbing streak artifacts and low contrast. These signal-to-noise ra...

Iterative algorithms such as MLEM are rapidly becoming the standard for reconstruction in emission computed tomography. However, such algorithms require arbitrary stopping criteria, are sensitive to noise artifacts, and require accelerated implementations that may not work well for all imaging situations. We have investigated several new iterative algorithms with likelihood-based objective func...

Dynamic positron emission tomography (PET) image reconstruction is challenging due to the low-count statistics of individual frames. This study proposes a novel framework aiming enhance quantitative accuracy dynamic frames via introduction priors based on multiscale superpixel clusters. The clusters are derived from pre-reconstruction composite images using clustering followed by fuzzy c-means ...