Real-Time Color overlay Cardiac Phase Contrast Spiral imaging at 3 Tesla
نویسندگان
چکیده
Introduction: The ability of MRI to quantify blood flow with high spatial and temporal resolution has made it a method of choice for accurate blood flow mapping in-vivo. The challenges comprise the development of techniques to accurately assess blood flow through heart valves by incorporating appropriate respiratory and cardiac motion compensation schemes as well as very fast measurement techniques to assess transient changes of blood flow such as ischemia-mediated flow responses. Nayak et al. have performed the real-time color flow MRI [1] in 1.5T systems. In this work we develop a fast spiral phase contrast pulse sequence and real-time reconstruction to compute both velocity and density maps in 3T systems. The spiral was chosen because of its insensitivity to motion and flow, and time efficiency. No breath holding or gating is required. We design two spiral acquisitions including uniform (uds) and variable (vds) density trajectories with different spatial resolutions. Image quality and performance were compared qualitatively by independent observers.
منابع مشابه
Real-time color flow MRI.
A real-time interactive color flow MRI system capable of rapidly visualizing cardiac and vascular flow is described. Interleaved spiral phase contrast datasets are acquired continuously, while real-time gridding and phase differencing is used to compute density and velocity maps. These maps are then displayed using a color overlay similar to what is used by ultrasound. For cardiac applications,...
متن کاملPositive contrast spiral imaging for visualization of commercial nitinol guidewires with reduced heating
BACKGROUND CMR-guidance has the potential to improve tissue visualization during cardiovascular catheterization procedures and to reduce ionizing radiation exposure, but a lack of commercially available CMR guidewires limits widespread adoption. Standard metallic guidewires are considered to be unsafe in CMR due to risks of RF-induced heating. Here, we propose the use of RF-efficient gradient e...
متن کاملVariable-density Spiral Imaging for Real-time Color Flow Cardiac Mri at 3t
Introduction The ability of MRI to quantify blood flow with high spatial and temporal resolution has made it a promising technique for accurate blood flow mapping in-vivo. Nayak et al. have performed the real-time color flow MRI [1] in 1.5T systems. In this work real-time color flow MRI is developed on a 3T system based on a spiral phase contrast pulse sequence and real-time reconstruction. Two...
متن کاملReal-time cardiac MRI at 3 tesla.
Real-time cardiac and coronary MRI at 1.5T is relatively "signal starved" and the 3T platform is attractive for its immediate factor of two increase in magnetization. Cardiac imaging at 3T, however, is both subtly and significantly different from imaging at 1.5T because of increased susceptibility artifacts, differences in tissue relaxation, and RF homogeneity issues. New RF excitation and puls...
متن کاملAssessment of cardiac time intervals using high temporal resolution real-time spiral phase contrast with UNFOLD-SENSE
Background Cardiac time intervals (CTI) provide information about systolic and diastolic function and can be measured using mitral valve (MV) and LV outflow tract (LVOT) Doppler velocity curves. Velocity curves produced by gated phase-contrast (PC) MR are not suitable for measurement of CTI due to distortion secondary to averaging across multiple heartbeats. Therefore, we developed a novel real...
متن کامل