Accelerated image reconstruction by a combined dual-matrix dual-voxel approach.

Accelerated image reconstruction by a combined dual-matrix dual-voxel approach. Phys Med Biol. 2020 Mar 24;: Authors: Goorden MC, Kamphuis C, Ramakers RM, Beekman FJ Abstract Today, Versatile Emission Computed Tomography (VECTor) technology using dedicated high-energy collimation enables simultaneous PET and SPECT down to 0.6 mm and 0.4 mm resolution in mice, respectively. We recently showed that for optimal resolution and quantitative accuracy of PET images the long tails of the 511 keV Point Spread Functions (PSFs) need to be fully modelled during image reconstruction. This, however, leads to very time consuming reconstructions and thus significant acceleration in reconstruction speed is highly desirable. To this end we propose and validate a combined dual-matrix dual-voxel (DM-DV) approach: for the forward projection the slowly varying PSF tails are modelled on a three times rougher voxel grid than the central parts of the PSFs, while in the backprojection only parts of the PSF-tails are included. DM-DV reconstruction is implemented in pixel-based OSEM (POSEM) and in a recently proposed accelerated pixel-based similarity-regulated OSEM (SROSEM). Both a visual assessment and a quantitative contrast-noise analysis confirm that images of a hot rod phantom are practically identical when reconstructed with standard POSEM, DM-DV-POSEM or DM-DV-SROSEM. However, compared to POSEM, DM-DV-POSEM can reach the same contrast 5.0 times faster, while with DM-DV-SROS...
Source: Physics in Medicine and Biology - Category: Physics Authors: Tags: Phys Med Biol Source Type: research

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ik Zalevsky Biomedical planar imaging using gamma radiation is a very important screening tool for medical diagnostics. Since lens imaging is not available in gamma imaging, the current methods use lead collimator or pinhole techniques to perform imaging. However, due to ineffective utilization of the gamma radiation emitted from the patient's body and the radioactive dose limit in patients, poor image signal to noise ratio (SNR) and long image capturing time are evident. Furthermore, the resolution is related to the pinhole diameter, thus there is a tradeoff between SNR and resolution. Our objectives are to re...
Source: Sensors - Category: Biotechnology Authors: Tags: Article Source Type: research
ConclusionsThe prognosis of diabetic patients for MACEs is different in men and women stratified by CAD. The worst prognosis for MACEs occurs in women with known CAD.
Source: Journal of Nuclear Cardiology - Category: Nuclear Medicine Source Type: research
AbstractPurpose of ReviewThe most pertinent clinical question in post-coronary computed tomography angiography (CCTA) patients is the assessment of the physiological significance of an anatomically identified stenosis. The clinical application of radionuclide MPI using single-photon emission computed tomography (SPECT) versus positron emission tomography (PET) in the evaluation and management of patients with an inconclusive CCTA is reviewed using a case-based approach.Recent FindingsRecent evidence suggests that CCTA is the most sensitive non-invasive test to exclude angiographic CAD and may be an effective first-line tes...
Source: Current Cardiology Reports - Category: Cardiology Source Type: research
ConclusionsCT-AC may allow brain perfusion SPECT to reflect more exact neuropathic changes in MCI that would cause progression of early AD. CT-AC in conjunction with voxel-based statistical analysis could possess higher diagnostic accuracy for exacerbation of disease implying early Alzheimer changes in MCI patients, with decreases in cerebral perfusion in the left temporal and limbic lobes representing good indicators.
Source: Annals of Nuclear Medicine - Category: Nuclear Medicine Source Type: research
AbstractBackgroundWe evaluated the performance of conventional (C) single-photon emission computed tomography (SPECT) and cadmium-zinc-telluride (CZT)-SPECT in a large cohort of patients with suspected or known coronary artery disease (CAD) and compared the diagnostic accuracy of the two systems using machine learning (ML) algorithms.Methods and ResultsA total of 517 consecutive patients underwent stress myocardial perfusion imaging (MPI) by both C-SPECT and CZT-SPECT. In the overall population, an excellent correlation between stress MPI data and left ventricular (LV) functional parameters measured by C-SPECT and by CZT-S...
Source: Journal of Nuclear Cardiology - Category: Nuclear Medicine Source Type: research
Ramesh S Doddamani, Manjari Tripathi, Raghu Samala, Mohit Agarwal, Bhargavi Ramanujan, Sarat P ChandraNeurology India 2020 68(2):270-273 The posterior quadratic epilepsy (PQE) is a form of a multilobar epilepsy, involving the temporal-parietal and occipital lobes. Basically, epilepsies with localized networks to the posterior temporal, posterior parietal, and occipital lobes can benefit from this type of surgery. Gliosis due to perinatal insult and cortical dysplasis and angiomas in Sturge Weber syndrome involving the PQ have often been cited in the literature as the etiology for PQE. However, before considering surgery, ...
Source: Neurology India - Category: Neurology Authors: Source Type: research
ConclusionsLeft ventricular volumes and ejection fraction assessed via ultra-low-dose CZT-SPECT showed very good correlation with the values obtained by MRI. A moderate correlation was found for myocardial mass.
Source: Journal of Nuclear Cardiology - Category: Nuclear Medicine Source Type: research
AbstractIn 2019, theJournal of Nuclear Cardiology published excellent articles pertaining to imaging in patients with cardiovascular disease. In this review, we will summarize a selection of these articles to provide a concise review of the main advancements that have recently occurred in the field and provide the reader with an opportunity to review a wide selection of articles. In the first article of this 2-part series, we focused on publications dealing with positron emission tomography, computed tomography, and magnetic resonance. This review will place emphasis on myocardial perfusion imaging using single-photon emis...
Source: Journal of Nuclear Cardiology - Category: Nuclear Medicine Source Type: research
AbstractIn 2019, theJournal of Nuclear Cardiology published excellent articles pertaining to imaging in patients with cardiovascular disease. In this review we will summarize a selection of these articles to provide a concise review of the main advancements that have recently occurred in the field and provide the reader with an opportunity to review a wide selection of articles. In this first article of this 2-part series we will focus on publications dealing with positron emission tomography, computed tomography and magnetic resonance. We will specifically discuss imaging as it relates to coronary artery disease, atherosc...
Source: Journal of Nuclear Cardiology - Category: Nuclear Medicine Source Type: research
We found it very accurate to evaluate the effect of abiraterone on prostate cancer using PSMA molecular imaging. PSMA imaging is expected to replace traditional imaging in prostate diagnosis and treatment AbstractTo investigate the feasibility and effectiveness of prostate ‐specific membrane antigen (PSMA) imaging to make response assessment regarding novel hormone treatment and to predict the outcomes for metastatic castration‐resistant prostate cancer (mCRPC) patients. This retrospective study enrolled 68 mCRPC patients who had daily received a novel hormone age nt named abiraterone. Tc‐99m PSMA single‐photon emi...
Source: Cancer Medicine - Category: Cancer & Oncology Authors: Tags: ORIGINAL RESEARCH Source Type: research
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