Background Advanced cardiac magnetic resonance (CMR) acquisitions often require long scan durations that necessitate respiratory navigator gating. This is particularly important in children with limited ability to hold their breath. We hypothesized that visual feedback of diaphragm position using an interactive videogame during CMR would increase navigator efficiency and improve image quality i...

PURPOSE To develop and assess a three-dimensional (3D) self-gated technique for the evaluation of myocardial infarction (MI) in mouse model without the use of external electrocardiogram (ECG) trigger and respiratory motion sensor on a 3T clinical MR system. METHODS A 3D T1-weighted GRE sequence with stack-of-stars sampling trajectories was developed and performed on six mice with MIs that wer...

Methods CosMo was implemented on a Philips 1.5T CMR system to prospectively acquire high resolution undersampled k-space LGE. The inner 10% of k-space is acquired within a 7 mm gating window. The rest of k-space is acquired without gating to finish the scan in a fixed time. Retrospectively, the k-space data acquired outside the gating window is discarded to generate the undersampled k-space. Th...

Purpose: Cardiac and respiratory motion artifacts are major challenges in cardiac MRI, and are conventionally suppressed by prospective ECG and diaphragm navigator gating, respectively. However, these approaches require time-consuming setup and prolonged acquisition times, and are susceptible to variations of heart rate or respiratory pattern. Further, they can become unreliable at higher field...

We report on initial patient studies to evaluate the performance of a commercial respiratory gating radiotherapy system. The system uses a breathing monitor, consisting of a video camera and passive infrared reflective markers placed on the patient's thorax, to synchronize radiation from a linear accelerator with the patient's breathing cycle. Six patients receiving treatment for lung cancer pa...

Respiratory and other regular motions during two-dimensional Fourier transform magnetic resonance imaging produce image artifacts consisting of local blurring and more or less regularly spaced "ghost" images propagating along the direction of the phase-encoding magnetic field gradient. The patterns of these ghost artifacts can be understood in terms of the technique of image production and basi...

Introduction The navigator gating technique reduced respiratory motion artifacts and is suited to abdominal MRI with patients who have difficulty in breath-holding. The motion adapted gating (MAG) approach [1] employs varying gating threshold depending on phase encoding steps, which accelerates gating to reduce scan time. However, even the MAG approach results in considerably longer scan time c...

Low-dose protocols for respiratory gating in cardiothoracic small-animal imaging lead to streak artifacts in the images reconstructed with a Feldkamp-Davis-Kress (FDK) method. We propose a novel prior- and motion-based reconstruction (PRIMOR) method, which improves prior-based reconstruction (PBR) by adding a penalty function that includes a model of motion. The prior image is generated as the ...