Rapid Robust Pediatric MRI

描述（由申请人提供）：动机：这是我们成功项目快速稳健儿科MRI的竞争性更新，R01 EB009690。MRI为儿童提供了极好的软组织对比和高分辨率，没有CT的电离辐射和癌症风险。然而，它的使用受到限制，因为儿童往往不能自愿暂停呼吸或忍受长时间的考试。MRI通常需要麻醉，伴有风险；因此，儿童往往完全缺乏横断面成像的好处，或者暴露在电离辐射下。之前的项目通过创建一个专用的儿科成像系统来解决这些问题。高度并行、高信噪比的3T接收阵列是专门为儿童身体成像设计和构建的。利用高信噪比，结合并行成像、新的运动校正算法和压缩感知（CS），加速重建扫描。并行计算重建算法在1分钟内生成三维体。由此产生的系统被广泛应用于临床实践，大大减少了麻醉，

DESCRIPTION (provided by applicant): Motivation: This is a competing renewal of our successful project Rapid Robust Pediatric MRI, R01 EB009690. MRI offers superb soft tissue contrast and high resolution for children, without the ionizing radiation and cancer risk of CT. However, its use has been limited as children often cannot voluntarily suspend respiration or tolerate long exams. MRI often requires anesthesia with attendant risk; hence, children often lack the benefits of cross-sectional imaging altogether or are exposed to ionizing radiation. The previous project addressed these concerns by creating a dedicated pediatric imaging system. Highly parallel, high SNR 3T receive arrays were designed and constructed specifically for pediatric body imaging. The high SNR was used to accelerate scans reconstructed with a combination of parallel imaging, new motion correction algorithms, and compressed sensing (CS). Parallel computing reconstruction algorithms produced 3D volumes in 1 minute. The resulting system is being used extensively in clinical practice, significantly reducing anesthesia, and has markedly increased our abdominal MRI utilization. Key technologies are now being commercialized with GE Healthcare, including the pediatric receive array, CS, and coil compression. Despite significant progress, with markedly reduced scan times, anesthesia has not been eliminated. Patient motion remains the main limitation. Therefore the major emphasis here is addressing motion through robust imaging, motion correction, and dynamic MRI. This will (1) extend the benefits of MRI to younger, less cooperative patients, (2) allow the correction and depiction of respiratory motion, and (3) provide the temporal resolution that captures the faster contrast dynamics in children for free-breathing 3D dynamic studies. Approach: The project has three interrelated development aims, validated by clinical studies. Aim 1 is to enable robust acquisition and reconstruction in the presence of motion in 3D studies. This uses robust parallel imaging calibration and reconstruction, outlier insensitive optimization and a new approach for measuring localized non-rigid motion throughout the body using array coil elements. A second aim is to develop ultrafast multi band 2D approaches for faster imaging of uncooperative patients. This freezes motion in each set of slices, simplifying motion correction over the volume. The impact of these developments in the clinic will then be assessed in the setting of appendicitis, a representative common and challenging pediatric abdominal imaging application. Then we will exploit temporal correlations and dynamics in time-resolved 3D contrast studies and further speed 2D scans, and again assess the impact in children with suspected appendicitis. Significance: This work will lead to fast, robust, broadly-applicable pediatric body MRI protocols with less anesthesia, making MRI safer, cheaper, and more available to children, transforming it into a workhorse modality and decreasing CT radiation burden. The techniques will facilitate wide application in the community setting and permit new MRI applications, for both pediatric and adult disease.