Accurate modeling of the respiratory cycle is important to account for the effect of organ motion on dose calculation for lung cancer patients. The aim of this study is to evaluate the accuracy of a respiratory model for lung cancer patients. Lujan et al. [Med. Phys. 26(5), 715-720 (1999)] proposed a model, which became widely used, to describe organ motion due to respiration. This model assume...

UNLABELLED Existing respiratory motion-correction methods are applied only to static PET imaging. We have previously developed an event-by-event respiratory motion-correction method with correlations between internal organ motion and external respiratory signals (INTEX). This method is uniquely appropriate for dynamic imaging because it corrects motion for each time point. In this study, we app...

Gated (4D) PET/CT has the potential to greatly improve the accuracy of radiotherapy at treatment sites where internal organ motion is significant. However, the best methodology for applying 4D-PET/CT to target definition is not currently well established. With the goal of better understanding how to best apply 4D information to radiotherapy, initial studies were performed to investigate the eff...

3T is feasible, and is advantageous due to the increased SNR and increased blood-myocardium contrast. Introduction: Three dimensional MR coronary imaging requires scan times longer than possible breath-hold durations. Respiratory motion compensation can be used to increase scan efficiency, reduce exam duration, and improve image quality. Previous studies of respiratory motion of the heart using...

With the arrival of increasingly higher resolution PET systems, small amounts of motion can cause significant blurring in the images, compared to the intrinsic resolutions of the scanners. In this work, we have reviewed advanced correction methods for the three cases of (i) unwanted patient motion, as well as motions due to (ii) cardiac and (iii) respiratory cycles. For the first type of motion...

AIM Respiratory motion affects cardiac PET-computed tomography (CT) imaging by reducing attenuation correction (AC) accuracy and by introducing blur. The aim of this study was to compare three approaches for reducing motion-induced AC errors and evaluate the inclusion of respiratory motion correction. MATERIALS AND METHODS AC with a helical CT was compared with averaged cine and gated cine CT...

INTRODUCTION: Correction of respiratory motion represents a major practical problem in quantitative myocardial perfusion MRI. Several registration methods exist to correct the motion of the heart in myocardial perfusion MRI [1-4]. However, these methods suffer from a number of important limitations: 1) they are limited to correction of translation (and in some cases rotation), 2) they require u...

Respiratory motion introduces uncertainties when planning and delivering radiotherapy for lung cancer patients. Cone-beam projections acquired in the treatment room could provide valuable information for building motion models, useful for gated treatment delivery or motion compensated reconstruction. We propose a method for estimating 3D+T respiratory motion from the 2D+T cone-beam projection s...

Rotational coronary angiography allows for volumetric imaging but requires cardiac and respiratory motion management to achieve meaningful reconstructions. Novel respiratory motion compensation algorithms based on data consistency conditions are applied directly in projection domain and, therefore, overcome the need for uncompensated reconstructions. Earlier, we combined single-frame background...

Respiratory motion poses significant challenges in image-guided interventions. In emerging treatments such as MR-guided HIFU or MR-guided radiotherapy, it may cause significant misalignments between interventional road maps obtained pre-procedure and the anatomy during the treatment, and may affect intra-procedural imaging such as MR-thermometry. Patient specific respiratory motion models provi...