The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Time of flight information is used in PET to improve image quality. However, the nature of the improvement and its relationship with the precision of the time of flight measurement remains to be well-characterized, particularly in the framework of iterative reconstruction. In this work, hot-spheres phantoms are imaged, and the list data are then degraded to simulate systems with poorer timing resolution...
Routine clinical myocardial perfusion (MP) PET imaging involves the use of cardiac gating only. Nonetheless, respiratory motion of the heart can considerably degrade the quality of MP images and the quantitative accuracy of myocardial uptake estimates. We first performed a quantitative evaluation of the degrading contributions of cardiac (C) and respiratory (R) motion, as well as non-motion factors...
Using a heart motion observer, we compared the performance of two image reconstruction techniques, a 3D OS-EM algorithm with post Butterworth spatial filtering and a 4D MAP-RBI-EM algorithm. The task was to classify gated myocardial perfusion (GMP) SPECT images of beating hearts with or without regional motion abnormalities. Noise-free simulated GMP SPECT projection data was generated from two 4D...
A promising approach in PET image reconstruction is to incorporate high resolution anatomical information (measured from MR or CT) taking the anato-functional mutual information (MI) or its joint entropy (JE) as the prior. The MI or JE of the images only classify voxels based on intensity, while neglecting structural spatial information. In this work, we have implemented an anatomy assisted MAP-EM...
The most active area in brain PET ligand development and imaging continues to involve receptor/transporter studies involving reversible binding. The focus of this work has been to develop direct 4D parametric image reconstruction techniques for reversible binding imaging. Based on a recent graphical analysis formulation, we developed a closed-form 4D EM algorithm to directly reconstruct distribution...
We developed a maximum a posterior (MAP) reconstruction method for PET image reconstruction incorporating MR image information, with the joint entropy between the PET and MR image features serving as the prior. A non-parametric method was used to estimate the joint probability density (JPD) of the PET and MR images. The sampling rate for Parzen window estimation of the JPD was studied for both simulated...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.