Zhixing Wang, Rajiv Ramasawmy, Ahsan Javed, John P. Mugler III, Craig H. Meyer, Adrienne E. Campbell-Washburn
{"title":"在 0.55 T 条件下，利用梯度补偿和回波重排同时进行的可变翻转角度三维螺旋进出涡轮自旋回波成像。","authors":"Zhixing Wang, Rajiv Ramasawmy, Ahsan Javed, John P. Mugler III, Craig H. Meyer, Adrienne E. Campbell-Washburn","doi":"10.1002/mrm.30380","DOIUrl":null,"url":null,"abstract":"<div>\n \n \n <section>\n \n <h3> Purpose</h3>\n \n <p>To develop single-slab 3D spiral turbo spin echo (spiral SPACE) for 1-mm<sup>3</sup> isotropic whole-brain T<sub>2</sub>-weighted imaging on a high-performance 0.55T scanner, with high scan efficiency from interleaved spiral-in-out trajectories, variable-flip-angle refocusing radiofrequency (RF) pulses, echo reordering, and concomitant-field compensation.</p>\n </section>\n \n <section>\n \n <h3> Methods</h3>\n \n <p>A stack-of-spirals (in-out waveforms) turbo-spin-echo acquisition was implemented with T<sub>2</sub>-weighed contrast. Gradient infidelity was corrected using the gradient impulse response function (GIRF), and concomitant-field compensation was used to correct for phase errors among echoes and during the readout windows. To maintain a long echo train (˜600 ms) within each shot, variable-flip-angle refocusing RF pulses were generated using extended-phase-graph analysis. An echo-reordering scheme provided a smooth signal variation along the echo direction in k-space. Images from spiral SPACE with and without concomitant-field compensation were compared with those from Cartesian SPACE in phantoms and 6 healthy volunteers.</p>\n </section>\n \n <section>\n \n <h3> Results</h3>\n \n <p>Phantom results demonstrated the improved performance of concomitant-field correction via sequence-based modifications and of GIRF–based trajectory estimation. Volunteer data showed that with concomitant-field correction and echo reordering, system imperfection associated image artifacts and blurring were substantially mitigated in spiral SPACE. Compared with Cartesian SPACE, spiral SPACE had an overall 15%–25% signal-to-noise ratio (SNR) improvement in both white matter and gray matter.</p>\n </section>\n \n <section>\n \n <h3> Conclusion</h3>\n \n <p>A 3D spiral-in-out SPACE acquisition with variable-flip-angles, concomitant-field compensation, and echo-reordering was demonstrated at 0.55 T, showing promising gains in SNR, compared with Cartesian SPACE.</p>\n </section>\n </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"93 4","pages":"1741-1750"},"PeriodicalIF":3.0000,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11782727/pdf/","citationCount":"0","resultStr":"{\"title\":\"Variable-flip-angle 3D spiral-in-out turbo spin-echo imaging using concomitant gradient compensation and echo reordering at 0.55 T\",\"authors\":\"Zhixing Wang, Rajiv Ramasawmy, Ahsan Javed, John P. Mugler III, Craig H. Meyer, Adrienne E. Campbell-Washburn\",\"doi\":\"10.1002/mrm.30380\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div>\\n \\n \\n <section>\\n \\n <h3> Purpose</h3>\\n \\n <p>To develop single-slab 3D spiral turbo spin echo (spiral SPACE) for 1-mm<sup>3</sup> isotropic whole-brain T<sub>2</sub>-weighted imaging on a high-performance 0.55T scanner, with high scan efficiency from interleaved spiral-in-out trajectories, variable-flip-angle refocusing radiofrequency (RF) pulses, echo reordering, and concomitant-field compensation.</p>\\n </section>\\n \\n <section>\\n \\n <h3> Methods</h3>\\n \\n <p>A stack-of-spirals (in-out waveforms) turbo-spin-echo acquisition was implemented with T<sub>2</sub>-weighed contrast. Gradient infidelity was corrected using the gradient impulse response function (GIRF), and concomitant-field compensation was used to correct for phase errors among echoes and during the readout windows. To maintain a long echo train (˜600 ms) within each shot, variable-flip-angle refocusing RF pulses were generated using extended-phase-graph analysis. An echo-reordering scheme provided a smooth signal variation along the echo direction in k-space. Images from spiral SPACE with and without concomitant-field compensation were compared with those from Cartesian SPACE in phantoms and 6 healthy volunteers.</p>\\n </section>\\n \\n <section>\\n \\n <h3> Results</h3>\\n \\n <p>Phantom results demonstrated the improved performance of concomitant-field correction via sequence-based modifications and of GIRF–based trajectory estimation. Volunteer data showed that with concomitant-field correction and echo reordering, system imperfection associated image artifacts and blurring were substantially mitigated in spiral SPACE. Compared with Cartesian SPACE, spiral SPACE had an overall 15%–25% signal-to-noise ratio (SNR) improvement in both white matter and gray matter.</p>\\n </section>\\n \\n <section>\\n \\n <h3> Conclusion</h3>\\n \\n <p>A 3D spiral-in-out SPACE acquisition with variable-flip-angles, concomitant-field compensation, and echo-reordering was demonstrated at 0.55 T, showing promising gains in SNR, compared with Cartesian SPACE.</p>\\n </section>\\n </div>\",\"PeriodicalId\":18065,\"journal\":{\"name\":\"Magnetic Resonance in Medicine\",\"volume\":\"93 4\",\"pages\":\"1741-1750\"},\"PeriodicalIF\":3.0000,\"publicationDate\":\"2024-11-20\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11782727/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Magnetic Resonance in Medicine\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1002/mrm.30380\",\"RegionNum\":3,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Magnetic Resonance in Medicine","FirstCategoryId":"3","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/mrm.30380","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING","Score":null,"Total":0}
引用次数: 0
摘要
目的：在高性能 0.55T 扫描仪上开发用于 1 mm3 各向同性全脑 T2 加权成像的单板三维螺旋涡轮自旋回波（螺旋 SPACE），通过交错螺旋进出轨迹、可变翻转角度重新聚焦射频（RF）脉冲、回波重排和同场补偿实现高效扫描：方法：采用 T2 权衡对比，进行螺旋堆叠（进出波形）涡轮自旋回波采集。利用梯度脉冲响应函数（GIRF）校正梯度失真，并利用共场补偿校正回波间和读出窗期间的相位误差。为了在每个镜头内保持长回波序列（˜600 ms），使用扩展相位图分析法生成了可变翻转角度的再聚焦射频脉冲。回波重排方案提供了沿 k 空间回波方向的平滑信号变化。在人体模型和 6 名健康志愿者身上比较了螺旋 SPACE 和笛卡尔 SPACE（带或不带共场补偿）的图像：结果：模型结果表明，通过基于序列的修改和基于 GIRF 的轨迹估计，共场校正的性能有所提高。志愿者的数据显示，通过共场校正和回波重排，在螺旋 SPACE 中，与系统不完善相关的图像伪影和模糊现象大大减少。与笛卡尔 SPACE 相比，螺旋 SPACE 在白质和灰质中的信噪比（SNR）总体提高了 15%-25%：与笛卡尔 SPACE 相比，在 0.55 T 条件下采用可变翻转角度、同时场补偿和回声重排的三维螺旋-进-出 SPACE 采集显示出了良好的信噪比提升效果。
Variable-flip-angle 3D spiral-in-out turbo spin-echo imaging using concomitant gradient compensation and echo reordering at 0.55 T
Purpose
To develop single-slab 3D spiral turbo spin echo (spiral SPACE) for 1-mm3 isotropic whole-brain T2-weighted imaging on a high-performance 0.55T scanner, with high scan efficiency from interleaved spiral-in-out trajectories, variable-flip-angle refocusing radiofrequency (RF) pulses, echo reordering, and concomitant-field compensation.
Methods
A stack-of-spirals (in-out waveforms) turbo-spin-echo acquisition was implemented with T2-weighed contrast. Gradient infidelity was corrected using the gradient impulse response function (GIRF), and concomitant-field compensation was used to correct for phase errors among echoes and during the readout windows. To maintain a long echo train (˜600 ms) within each shot, variable-flip-angle refocusing RF pulses were generated using extended-phase-graph analysis. An echo-reordering scheme provided a smooth signal variation along the echo direction in k-space. Images from spiral SPACE with and without concomitant-field compensation were compared with those from Cartesian SPACE in phantoms and 6 healthy volunteers.
Results
Phantom results demonstrated the improved performance of concomitant-field correction via sequence-based modifications and of GIRF–based trajectory estimation. Volunteer data showed that with concomitant-field correction and echo reordering, system imperfection associated image artifacts and blurring were substantially mitigated in spiral SPACE. Compared with Cartesian SPACE, spiral SPACE had an overall 15%–25% signal-to-noise ratio (SNR) improvement in both white matter and gray matter.
Conclusion
A 3D spiral-in-out SPACE acquisition with variable-flip-angles, concomitant-field compensation, and echo-reordering was demonstrated at 0.55 T, showing promising gains in SNR, compared with Cartesian SPACE.
期刊介绍：
Magnetic Resonance in Medicine (Magn Reson Med) is an international journal devoted to the publication of original investigations concerned with all aspects of the development and use of nuclear magnetic resonance and electron paramagnetic resonance techniques for medical applications. Reports of original investigations in the areas of mathematics, computing, engineering, physics, biophysics, chemistry, biochemistry, and physiology directly relevant to magnetic resonance will be accepted, as well as methodology-oriented clinical studies.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
