PURPOSE Iterative reconstruction algorithms are becoming more commonly employed in positron emission tomography (PET) imaging; however, the quantitative accuracy of the reconstructed images still requires validation for various levels of contrast and counting statistics. METHODS The authors present an evaluation of the quantitative accuracy of the 3D maximum a posteriori (3D-MAP) image recons...

Background: The quality of positron emission tomography/computed tomography (PET/CT) images plays an important role in tumor detection. This imaging method often yields poor-quality overweight patients due to the high level noise, originating from scattering and photon attenuation. Objectives: point spread function (PSF) is mostly used enhance spatial resolution signal-to-noise ratio (SNR); how...

Zusammenfassung: Das Auflösungsvermögen der Positronen-EmissionsTomographie resultiert aus einem Zusammenspiel verschiedenster Parameter, die in ihrer Summe Grenzen der Detektierbarkeit kleiner Objekte festlegen. Diese Grenzen sollten an Hand von Simulationen mit einem Software-Phantom in Abhängigkeit von Akquisitionszeit und Aktivitätskontrast Objekt / Hintergrund ermittelt werden. Die Rekonst...

The Voxel Imaging PET (VIP) Pathfinder project intends to show the advantages of using pixelated solid-state technology for nuclear medicine applications. It proposes designs for Positron Emission Tomography (PET), Positron Emission Mammography (PEM) and Compton gamma camera detectors with a large number of signal channels (of the order of 106). For Compton camera, especially with a large numbe...

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...

OBJECTIVE The present study is aimed at contributing to identify the most appropriate OSEM parameters to generate myocardial perfusion imaging reconstructions with the best diagnostic quality, correlating them with patients' body mass index. MATERIALS AND METHODS The present study included 28 adult patients submitted to myocardial perfusion imaging in a public hospital. The OSEM method was ut...

Introduction A system matrix with high accuracy is essential when applying iterative reconstruction algorithms like MLEM and OSEM in PET imaging. However, using Monte Carlo simulations may not always be feasible, as they take a considerable amount of time. The detector response function (DRF) model has proven to be a good alternative [1]. Further accelerating the execution of this model is bene...