نتایج جستجو برای: spect reconstruction
تعداد نتایج: 133449 فیلتر نتایج به سال:
BACKGROUND Full Monte Carlo (MC)-based SPECT reconstructions have a strong potential for correcting for image degrading factors, but the reconstruction times are long. The objective of this study was to develop a highly parallel Monte Carlo code for fast, ordered subset expectation maximum (OSEM) reconstructions of SPECT/CT images. The MC code was written in the Compute Unified Device Architect...
BACKGROUND The use of a normal database for [123I]FP-CIT SPECT imaging has been found to be helpful for cases which are difficult to interpret by visual assessment alone, and to improve reproducibility in scan interpretation. The aim of this study was to assess whether the use of different tomographic reconstructions affects the performance of a normal [123I]FP-CIT SPECT database and also wheth...
Abstract Background The digital cadmium–zinc–telluride (CZT)-based SPECT system has many advantages, including better spatial and energy resolution. However, the impacts of different acquisition reconstruction parameters on CZT quantification might still need to be validated. This study aimed evaluate (the main window time per frame) number iterations, subsets in iterative reconstruction, post-...
Pinhole SPECT for small animal has become a routine procedure in many applications of molecular biology and pharmaceutical development. There is an increasing demand in the whole body imaging of lab animals. A simple and direct solution is to scan the object along a helical trajectory, similar to a helical CT scan. The corresponding acquisition time can be greatly reduced, while the over-lappin...
Single photon emission computed tomography (SPECT) is a well established clinical tool for functional imaging. A limitation of current SPECT systems is the use of mechanical collimation, where only a small fraction of the emitted photons is actually used for image reconstruction. This results in large noise level and finally in a limited spatial resolution. In order to decrease the noise level ...
UNLABELLED The accuracy of clinical SPECT is highly dependent on the acquisition and processing parameters, which are selected according to the clinical task. These parameters are usually set within protocols in order to allow for standardization from one study to another and to speed up the clinical routine. METHODS In the first part of this work, tomographic images of a Jaszczak phantom wer...
In the past decades, analytical (non-iterative) methods have been extensively investigated and developed for the reconstruction of three-dimensional (3D) single-photon emission computed tomography (SPECT). However, it becomes possible only recently when the exact analytic non-uniform attenuation reconstruction algorithm was derived. Based on the explicit inversion formula for the attenuated Rad...
We present a post-reconstruction motion-compensated spatio-temporal filtering method for noise reduction in cardiac gated SPECT images. SPECT imaging suffers from low photon count due to radioactive dose limitations resulting in a high noise level in the reconstructed images. This is especially true in gated cardiac SPECT where the total number of counts is divided into a number of gates (time ...
Whether a patient with head and neck cancer has mandibular invasion or not is important in determining the method of resection surgery. But, no modality is adequately reliable when used alone in the evaluation of mandibular invasion. Therefore, to more accurately diagnose mandibular invasion in head and neck cancer, we used a new modality, namely, 99mTc methylene diphosphonate (MDP) or 99mTc hy...
PURPOSE We evaluated an off set reconstruction method for single photon emission computed tomography (SPECT), and compared it with the conventional on set reconstruction method, using sampling angles of 2, 4, and 6 degrees. METHOD A triple-detector system was used. In the off-set acquisition, sampling angles of the opposite detector were shifted 1/2 of the sampling angles of 2, 4, and 6 degre...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید