A5036827849- Advanced MRI Techniques and Applications
- Cardiac Imaging and Diagnostics
- Cerebrovascular and Carotid Artery Diseases
- Atomic and Subatomic Physics Research
- Ultrasound and Hyperthermia Applications
- Photoacoustic and Ultrasonic Imaging
- Medical Imaging Techniques and Applications
- Cardiovascular Function and Risk Factors
- Cardiovascular Health and Disease Prevention
- Acute Ischemic Stroke Management
- MRI in cancer diagnosis
- Advanced Neuroimaging Techniques and Applications
- NMR spectroscopy and applications
- Cardiac Valve Diseases and Treatments
- Intracranial Aneurysms: Treatment and Complications
- Infrared Thermography in Medicine
- Ultrasound Imaging and Elastography
- Cardiac electrophysiology and arrhythmias
- Acute Myocardial Infarction Research
- Advanced X-ray and CT Imaging
- Peripheral Artery Disease Management
- Antiplatelet Therapy and Cardiovascular Diseases
- Advanced NMR Techniques and Applications
- Cardiac Structural Anomalies and Repair
- Advanced X-ray Imaging Techniques
Siemens (Singapore)
2018-2024
Shenzhen Institutes of Advanced Technology
2011-2018
Chinese Academy of Sciences
2011-2018
Siemens Healthcare (Germany)
2016
Siemens Healthcare (United States)
2002-2012
University Town of Shenzhen
2012
Shenzhen University
2012
Siemens (Germany)
2002-2010
The Ohio State University
2009
Siemens (United States)
2008
T2-Weighted (T2W) magnetic resonance imaging (MRI) pulse sequences have been used to detect edema in patients with acute myocardial infarction and differentiate from chronic infarction. T2W suffered several problems including (i) signal intensity variability caused by phased array coils, (ii) high slow moving ventricular chamber blood that can mimic mask elevated T2 sub-endocardial myocardium, (iii) motion artifacts, (iv) the subjective nature of image interpretation. In this work we...
Abstract This clinical trial was performed to evaluate the safety and feasibility of interactive MR‐guided radiofrequency (RF) interstitial thermal ablation (ITA) entirely within MR imager. RF‐ITA on 11 intra‐abdominal metastatic tumors during 13 sessions. The RF electrode placed under guidance a .2‐T system using rapid fast imaging with steady state precession (FISP) true FISP images. A custom 17‐gauge used modified in four sessions allow circulation iced saline for cooling ablation. Tissue...
Following administration of Gd-DTPA, infarcted myocardium exhibits delayed enhancement and can be imaged using an inversion-recovery sequence. A conventional segmented acquisition requires a number breath-holds to image the heart. Single-shot phase-sensitive (PSIR) true-FISP may combined with parallel imaging SENSE achieve high spatial resolution. SNR improved by averaging multiple motion-corrected images acquired during free breathing. PSIR techniques have demonstrated benefits including...
Abstract Purpose: To evaluate the effectiveness of flow‐sensitive dephasing (FSD) magnetization preparation in improving blood signal suppression three‐dimensional (3D) turbo spin‐echo (TSE) sequence (SPACE) for isotropic high‐spatial‐resolution carotid arterial wall imaging at 3T. Materials and Methods: The FSD‐prepared SPACE (FSD‐SPACE) was implemented by adding two identical FSD gradient pulses right before after first refocusing 180°‐pulse all three orthogonal directions. Nine healthy...
Abstract Quantitative T 2 mapping was recently shown to be superior ‐weighted imaging in detecting changes across myocardium. Pixel‐wise is sensitive misregistration between the images used generate parameter map. In this study, utility of two motion‐compensation strategies—(i) navigator gating with prospective slice correction and (ii) nonrigid registration—was investigated for myocardial short axis horizontal long views. Navigator provides respiratory motion compensation, whereas...
To study the effect of imaging parameters on contrast T1 weighted SPACE (Sampling Perfection with Application optimized Contrast using different angle Evolutions, a 3D TSE variant) at 3 T for high resolution intracranial plaques before and post-gadolinium induced enhancement, evaluate its relevance to patients atherosclerosis.Optimized giving good between vessel wall cerebrospinal fluid within specific scan time reasonable coverage were found by simulation validated in healthy volunteer...
Abstract Purpose To evaluate the effectiveness of a T2‐magnetization preparation scheme for improving coronary artery imaging with true fast steady‐state precession (True‐FISP). Materials and Methods Simulations were performed to compare blood‐myocardium signal difference no T2‐preparation that various times (24, 40, 60 msec) using an electrocardiogram (ECG)‐triggered, segmented True‐FISP acquisition. Seven volunteers imaged delineation True‐ FISP optimize time. Results showed improved...
The administration of intravenous cangrelor at reperfusion achieves faster onset platelet P2Y12 inhibition than oral ticagrelor and has been shown to reduce myocardial infarction (MI) size in the preclinical setting. We hypothesized that will MI prevent microvascular obstruction patients with ST-segment-elevation undergoing primary percutaneous coronary intervention.
Abstract An electrocardiogram (ECG)‐triggered, magnetization‐prepared, segmented, 3D true fast imaging with steady‐state precession (true‐FISP) sequence fat saturation was recently proposed for coronary artery imaging. A magnetization preparation scheme consisting of an α/2 radiofrequency (RF) pulse followed by 20 constant flip angle dummy RF cycles used to reduce signal oscillations in the approach steady state. However, if large resonance offsets on order 70–100 Hz are present, significant...
Abstract Radiofrequency (RF) energy has many advantages in thermal tumor ablation protocols. With the recent development of open MRI systems, interventional procedures, including ablation, have become focus great research interest. However, significant interference between RF generators and MR imagers prevented simultaneous imaging and, until now, limited role RF‐based therapy MRI. Here, a simple switching circuit designed with consideration patient safety provides compatibility systems...
Exercise cardiovascular magnetic resonance (ExCMR) has great potential for clinical use but its development been limited by a lack of compatible equipment and robust real-time imaging techniques. We developed an exCMR protocol using in-scanner cycle ergometer assessed performance in differentiating athletes from non-athletes. Free-breathing CMR (1.5T Aera, Siemens) was performed 11 (5 males; median age 29 [IQR: 28–39] years) 16 age- sex-matched healthy volunteers (7 26 [interquartile range...
Abstract Phase‐contrast magnetic resonance imaging (PC‐MRI) is used routinely to measure fluid and tissue velocity with a variety of clinical applications. methods require acquisition additional data enable phase difference reconstruction, making real‐time problematic. Shared Velocity Encoding (SVE), method devised improve the effective temporal resolution phase‐contrast imaging, was implemented in pulse sequence segmented echo planar readout. The effect SVE on peak measurement investigated...
Abstract The size and function of the left atrium (LA) right (RA) are related closely with prognosis cardiovascular diseases. However, their normal reference values, as measured by cardiac magnetic resonance (CMR), not well established in Chinese populations. Healthy subjects (n = 135, 66 males, age 23–83 years) without risk factors were recruited. We imaged LA RA all using short axis long slices steady-state free precession (SSFP) sequences a 3.0T scanner. functional parameters measured....
Abstract Purpose: To evaluate the feasibility of dark blood fast spin echo (FSE) T1‐weighted–Sampling Perfection with Application optimized Contrasts using different flip angle Evolution (T1w‐SPACE) sequence in assessing whole body arterial wall information from extracranial carotids to popliteal artery. Materials and Methods: Twenty‐eight subjects were subjected noncontrast, magnetic resonance angiography (DB‐WBMRA) a T1w‐SPACE for each individual stations: carotid artery, thoracic aorta,...
Myocardial fibrosis is a common pathophysiological process that related to ventricular remodeling in congenital heart disease. However, the presence, characteristics, and clinical significance of myocardial Ebstein's anomaly have not been fully investigated. This study aimed evaluate using cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) T1 mapping techniques, explore adolescent adult patients with anomaly. Forty-four consecutive unrepaired (34.0 ± 16.2 years; 18...
We investigated the feasibility of using echo-shifted fast low-angle shot (FLASH) for temperature-monitored thermotherapeutic procedures in a 0.2 T interventional magnetic resonance (MR) scanner. Based on proton frequency shift technique, modified FLASH has sufficiently high signal-to-noise ratio to provide accurate temperature maps with short scan times, i.e., 5 seconds phantoms (TR = 20.5 msec; effective TE 30 one echo shift; NSA 2) and ex vivo experiments 19.4 28.9 3 msec, 1) an case. The...
Abstract Purpose To develop and test a delayed‐enhancement imaging method for improving the contrast between myocardial infarction (MI) blood pool. Materials Methods The T 2 of is significantly longer than that acute or chronic MI. proposed multicontrast (MCODE) produces series images with both 1 weightings, which provides excellent normal infarcted myocardium, Results subendocardial border MI pool was easily discriminated in ‐weighted image. measured MI‐to‐blood contrast‐to‐noise ratio...
Abstract Purpose To compare two multislice turbo spin‐echo (TSE) carotid artery wall imaging techniques at 1.5 T and 3.0 T, to investigate the feasibility of higher spatial resolution T. Materials Methods Multislice proton density‐weighted (PDW), T2‐weighted (T2W), T1‐weighted (T1W) inflow/outflow saturation band (IOSB) rapid extended coverage double inversion‐recovery (REX‐DIR) TSE was performed on six healthy volunteers using time‐, coverage‐, resolution–matched (0.47 × 0.47 3 mm )...
Abstract Purpose To evaluate the feasibility of a multi‐station three dimensional (3D) T1‐weighted turbo spin echo (TSE) dark‐blood Sampling Perfection with Application optimized Contrasts using different flip angle Evolution sequence (T1w‐SPACE), to assess aorta, iliac, and superficial femoral (SFA) arteries (inflow vessels) by comparing it contrast enhanced MR angiography (CE‐MRA) identical resolution. Materials Methods A total 6 volunteers 14 peripheral arterial disease (PAD) patients...
Accurate measurement of spatially variant noise in MR images acquired using parallel imaging techniques is challenging. Image-based methods such as the subtraction method proposed by National Electrical Manufacturers Association or multiple acquisition often cannot be applied vivo due to motion and/or dynamic contrast changes. Based on Karhunen-Loeve transform and random matrix theory, we propose a novel accurately assess variance image series bearing temporal redundancy. The fits...
Proton resonance frequency shift (PRFS) MR thermometry is commonly used to measure temperature in thermotherapy. The method requires a baseline map and therefore motion sensitive. Several referenceless methods were proposed address this problem but their performances have never been compared. This study compared the performance of five through simulation, heating ex vivo tissues imaging brain liver healthy volunteers. Mean, standard deviation, root mean square, 2/98 percentiles error as...
Abstract TSENSE and TGRAPPA are autocalibrated parallel imaging techniques that can improve the temporal resolution and/or spatial in dynamic magnetic resonance applications. In its original form, uses low‐pass filtering of undersampled frames to create sensitivity map. a sliding‐window moving average when finding autocalibrating signals. Both methods suboptimal least‐squares sense may give rise mismatches between k ‐space raw data corresponding coil sensitivities. Such result aliasing...