Yuanyuan Liu^1,2, Lanlan Gao³, Shuheng Zhang³, Zhuoxu Cui⁴, Qingyong Zhu⁴, Haifeng Wang¹, Dong Liang¹, and Yanjie Zhu^1
1Paul C. Lauterbur Research Center for Biomedical Imaging,Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, ²National Innovation Center for Advanced Medical Devices, Shenzhen, China, ³United Imaging Healthcare, Shanghai, China, ⁴Research Center for Medical AI,Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China

MR quantitative T_1ρ mapping has gained increasing attention due to its capability in studying low-frequency motional processes and chemical exchange in biological tissues. At ultra-high fields, the chemical exchange and proton diffusion in biological tissues should be more prominent. In this study, for the first time, we aim to test the feasibility of T_1ρ mapping of brain at 5T and evaluate the T_1ρ values estimated from datasets using both 3T and 5T scanners.

ling huang¹, hui bai¹, HAI ZHONG¹, and WEI QIANG DOU^2
1the second hospital of shandong university, JINAN, China, ²GE Healthcare, MR Research, BEIJING, China

The main purpose was to evaluate the gamma knife radiosurgery(GKRS) treatment effect of multiple kinds of brain tumors by MR perfusion imaging. We collected 45 patients with three kinds of brain tumors treated with GKRS. Perfusion imaging, including 3D-ASL and DSC-PWI, was performed before and after treatment. ASL-rCBF, DSC-rCBF and DSC-rCBV decreased significantly after GKRS treatment, and ASL-rCBF before GKRS treatment showed the most robust performance with high AUC in predicting GKRS treatment effect. With these findings, MR perfusion imaging can be considered a time and effective method understanding the treatment effect of GKRS for brain tumor patients.

Qinhe Zhang¹, Nan Wan¹, Xue Ren¹, Peng Sun², Xu Dai³, Liangjie Lin⁴, Zhigang Wu⁵, Jiazheng Wang⁴, and Ailian Liu^1
1The first affiliated hospital of Dalian Medical University, Dalian, China, ²Philips health, Wu han, China, ³Philips health, Shenyang, China, ⁴Philips health, Beijing, China, ⁵Philips health, Shen zhen, China

Extracellular volume (ECV) fraction might represent a useful parameter for the noninvasive quantification of pancreatic fibrosis, and the proton density fat fraction (FF) of pancreas can be obtained by mDxion Quant. Here, we hypothesized that pancreatic ECV and FF, for evaluation of pancreatic fibrosis and fat content, can be used to assess patients with liver cirrhosis. Results indicated that pancreatic ECV at 60 mins after contrast agent administration showed a statistical difference between liver cirrhosis patients and controls. A significant correlation was observed between pancreatic FF and ECV at 5 mins after administration. 

Tiexin Cao¹, Lin Lin¹, Yunjing Xue¹, Pu-Yeh Wu², Rufei Zhang¹, and Lingmin Zheng^1
1Fujian Medical University Union Hospital, Fuzhou, China, ²GE Healthcare, Beijing, China

In daily clinical practice, preoperative grading of meningioma is particularly important for selecting the best treatment strategy. Our hypothesis is that a combination of T1 mapping and diffusion weighted imaging (DWI) based on histogram analysis would be useful for differentiating between low-grade and high-grade meningiomas. Our study, for the first time, provides evidence that T1 mapping may be an imaging biomarker for differentiating grades and predicting the proliferation potential of meningiomas. The combination of T1 mapping and DWI showed the highest diagnostic performances in grading meningiomas.

Qiaoli Yao¹, Kan Deng², Zhiyu Liang¹, and Yikai Xu^1
1Medical Image Center, Nanfang Hospital, Southern Medical University, Guangzhou, China, ²Philips Healthcare, Guangzhou, China

As grade Ⅱ and Ⅲ gliomas are difficult to distinguish in preoperative, this study attempted to find the best perfusion parameters for identifying grade Ⅱ/Ⅲ glioma by machine learning model. The machine learning model showed robust performance when using the parameters of volume transfer coefficient (K^trans) and mean transit time (MTT) derived from the dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast (DSC) imaging, which indicated that the combination of DCE and DSC perfusion techniques is expected to further improve the differential diagnosis of grade Ⅱ and Ⅲ gliomas.
 

Jingcheng Huang¹, Junfei Chen¹, Weiqiang Dou², Jing Ye¹, Wei Xia¹, and Xianfu Luo^1
1Clinical Medical School of Yangzhou University, Northern Jiangsu People’s Hospital, Yangzhou, China, Yangzhou City, China, ²GE Healthcare, MR Research China, Beijing, P.R. China, Beijing City, China

In this study, we aimed to investigate the feasibility of amide proton transfer weighted (APTw)  imaging for differentiating hepatocellular carcinoma(HCC) from intrahepatic cholangiocarcinoma(ICC) patients. With the APTw imaging metric of magnetization transfer ratio asymmetry (MTRasym), significantly different magnetization transfer ratio asymmetry (MTRasym) values, a typical metric of APTw imaging, were shown between hepatocellular carcinoma and intrahepatic cholangiocarcinoma. With this finding, APTw imaging could be considered an effective imaging biomarker for differentiating HCC from ICC.

Shuang Chen¹, Xiaoduo Yu¹, Qi Zhang¹, Jieying Zhang¹, Lizhi Xie², and Han Ouyang^1
1National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, ²GE Healthcare, MR Research, Beijing, China

To discuss the histogram parameters diagnostic value of Magnetic Resonance Image Compilation (MAGiC) sequence for differentiation of early-stage endometrial carcinoma (EC) from normal endometrium of health control (HC).

Yuuzo Kamiguchi¹ and Sadanori Tomiha^2
1Advanced Technology Research Dept., CANON MEDICAL SYSTEMS CORPORATION, Kawasaki-shi, Japan, ²Advanced Technology Research Dept., CANON MEDICAL SYSTEMS CORPORATION, Ootawara-shi, Japan

In quantitative imaging of the brain, it is common that tissues having different T1 and T2 values are mixed in a voxel and exchange proton each other. So multiparametric imaging method of brain microstructure is attracting much attention. In this study, we demonstrated that quantitative maps of 12 parameters in the brain 4-pool model (2 free water pools with exchange and 2 semi-solid water pools) were estimated within 10 seconds using deep learning from the data acquired by the tsDESPOT sequence.

Tao Zu¹, Yi-Cheng Hsu², Yi Sun², Dan Wu^1,3,4, and Yi Zhang^1,3,4
1Key Laboratory for Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China, ²MR Collaboration, Siemens Healthcare Ltd., Shanghai, China, ³Department of Neurology, The First Affiliated Hospital, Zhejiang University, Hangzhou, China, ⁴Cancer Center, Zhejiang University, Hangzhou, China

The relaxation time mapping has proven to be an important diagnostic tool, but it is limited by the prolonged scan time due to the measurements of multiple frames at the same location. In this study, the recently proposed auto-calibrated reconstruction method by joint k-space and image-space parallel imaging (KIPI) is utilized for the acceleration of relaxation time mapping. Combined with the ESPIRiT method, KIPI generates improved coil sensitivity maps and allows an acceleration factor of up to 4-fold for acquiring source images, yielding the accurate parameter map without obvious errors or artifacts.

Zijing Zhang^1,2, Huihui Ye¹, Long Wang³, Kawin Setsompop⁴, Huafeng Liu¹, and Berkin Bilgic^2,5,6
1State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China, ²Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States, ³Subtle Medical Inc, Menlo Park, CA, United States, ⁴Radiological Sciences Laboratory, Stanford University, Stanford, CA, United States, ⁵Department of Radiology, Harvard Medical School, Boston, MA, United States, ⁶Harvard-MIT Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States

BUDA-SAGE is an efficient multi-shot echo‐planar imaging (EPI) sequence that provides multiple distortion-free T₂^*-, T₂^’- and T₂-weighted contrasts for quantitative mapping. In this work, we employ Slider encoding to reach 1 mm isotropic resolution by performing super-resolution reconstruction on volumes acquired with 2 mm slice thickness. A self-supervised neural network MR-Self2Self (MR-S2S) was utilized to perform denoising to boost SNR. Estimated quantitative maps showed consistent values with conventional mapping methods in phantom and in-vivo measurements. We demonstrate that BUDA-SAGE acquisition with self-supervised denoising and Slider encoding enables rapid, distortion-free, whole-brain T₂/T₂^* mapping at 1 mm isotropic resolution under 90 seconds.

Ziming Xu¹, Xiaoyan Bai², Yajie Wang¹, Zhiye Li², Jiaqi Dou¹, Binbin Sui³, and Huijun Chen^1
1Center for Biomedical Imaging Research, School of Medicine, Tsinghua University, Beijing, China, ²Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing Neurosurgical Institute, Beijing, China, ³Tiantan Neuroimaging Center of Excellence, China National Clinical Research Center for Neurological Diseases, Beijing, China

In vivo quantitative mapping of intracranial atherosclerotic plaque is very important for plaque characterization. Previous intracranial plaque quantitative studies were usually carried out ex vivo, while studies of in vivo intracranial plaque mapping have rarely been reported. In this study, the in vivo feasibility of quantitative T2^* mapping of intracranial plaque at 7T MRI had firstly been demonstrated. Symptomatic patients showed significantly lower intraplaque T2^* values than asymptomatic patients (26.33 ± 7.16 vs. 33.47 ± 8.68 ms, p = 0.048). This quantitative and noninvasive assessment may serve as one potential tool to characterize and evaluate intracranial atherosclerotic plaques.

Junjiao Hu¹, Huiting Zhang², Jun Liu¹, Hu Guo², Shan Jiang¹, and Weijun Situ^1
1Department of Radiology,The Second Xiangya Hospital, Central South University, Changsha, China, ²MR Scientific Marketing, Siemens Healthineers, Wuhan, China,, Wuhan, China

The purpose of this study to assess image quality and T1 value value between variable flip angle (VFA-T1) and StarVIBE (StarVIBE-T1) methods using breath-holding and free breathing, respectively. Compared with VFA-T1 method, StarVIBE-T1 had better image quality, including overall image quality, blurring, and clearer edge of lesions, especially for the patients without breath-holding. The T1 values from the two methods had high correlation and moderate agreement.

Tokunori Kimura^1
1Radiological Science, Shizuoka College of Medical care Science, Hamamatsu, Japan

A T2-based water suppressed diffusion MRI (T2wsup-dMRI) was proposed to solve the CSF partial volume effects (CSF-PVE) in quantifying several parameters in tissue. There a simple closed form (CF) algorithm was used but  errors were increased when tissue T2, T2t is long (> 100ms). In this study, to reduce those errors, several algorithms using least-squares (LSQ) fitting method were assessed by simulation and in vivo data. Through this study, the combined algorithm of single and bi-exponential LSQ applied in 2D (TE, b) space is the best in keeping those accuracies especially when applied in random data pattern.

Hyunyeol Lee^1,2 and Felix Wehrli^2
1Electronics Engineering, Kyungpook National University, Daegu, Korea, Republic of, ²Radiology, University of Pennsylvania, Philadelphia, PA, United States

qBOLD permits noninvasive measurements of the two critical determinants of the BOLD signal, i.e., deoxygenated-blood-volume (DBV) and venous-oxygen-saturation-level (Y_v), and along with CBF imaging, the cerebral metabolic rate of oxygen (CMRO₂). Two major challenges in qBOLD are 1) separation of heme-originated R₂′ from other signal sources, and 2) subsequent extraction of  DBV and Y_v. We had previously addressed these issues by developing a prior-guided qBOLD method. Here, we aimed to evaluate the method's utility in 3D CMRO₂ mapping. Results suggest feasibility of the new qBOLD method as a practical means for measuring neurometabolic parameters over an extended brain coverage.

Zihan Zhou¹, Qing Li², Congyu Liao^3,4, Xiaozhi Cao^3,4, Huihui Ye⁵, Jianhui Zhong^1,6, and Hongjian He^1
1Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, China, ²MR Collaborations, Siemens Healthineers Ltd, Shanghai, China, ³Department of Radiology, Stanford University, Stanford, CA, United States, ⁴Department of Electrical Engineering, Stanford University, Stanford, CA, United States, ⁵State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China, ⁶Department of Imaging Sciences, University of Rochester, Rochester, NY, United States

Optimization of MRF (MR fingerprinting) sequence is important for encoding MR tissue parameters with the maximal SNR for better quantification of representative tissues of WM, GM and CSF. Here, we targeted ultrashort T2 tissues and proposed an optimized acquisition parameter patterns for 3D ultrashort echo time MRF sequence with the goal of achieving higher quantification accuracy for myelin-proton based on Cramér‐Rao Lower Bound. Our results show that the optimized UTE-MRF sequence achieved high accuracy in myelin-proton quantification and whole-brain myelin-proton imaging in 15 min with 1mm isotropic resolution. The optimization also opens the door to further reduce scan time.

Man-Chin Chen¹, Huai-Zhe Yang², Cheng-Chia Lee^2,3, Hsiu-Mei Wu^3,4, and Chia-Feng Lu^1
1Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan, ²Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan, ³School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ⁴Department of Radiology, Taipei Veteran General Hospital, Taipei, Taiwan

Several issues concerning the optimal parameters of radiosurgery treatment, the occurrence of radiation-induced edema, and other postoperative complications remain unsolved in treating meningiomas. We aimed to determine whether combining radiomic features with clinical risk factors can improve the prediction of edema occurrence after Gamma-Knife radiosurgery (GKRS). Pre-GKRS MR radiomic features and clinical features were used to construct the prediction model. The model combing radiomic features and clinical features showed the highest performance for prediction of post-GKRS edema (AUC＝0.79). The outcomes of this study can provide a risk assessment to facilitate precision medicine in treating meningiomas.

Ming Zhang¹, Haidong Li¹, Hongchuang Li¹, Xiuchao Zhao¹, Xiaoling Liu¹, Yeqing Han¹, Xianping Sun¹, Xin Lou², Chaohui Ye¹, and Xin Zhou^1
1Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences- Wuhan National Laboratory for Optoelectronics, Wuhan, China, ²Department of Radiology, Chinese PLA General Hospital, Beijing, China

Pulmonary compliance is generally measured using ventilator and esophageal balloon in clinical practice, and only global compliance could be obtained. In this study, we proposed a method for imaging pulmonary compliance using hyperpolarized (HP) ¹²⁹Xe MRI. Lung compliance derived by HP ¹²⁹Xe MRI could be used for quantifying the injuries caused by fibrosis in rats. 

Yiwei Pan¹, Shuying Liu², Yao Zeng¹, Chenfei Ye³, Hongwen Qiao², Tianbing Song², Haiyan Lv⁴, Piu Chan², Jie Lu², and Ting Ma^1,2,3
1Department of Electronic and Information Engineering, Harbin Institute of Technology at Shenzhen, Shenzhen, China, ²Xuanwu Hospital Capital Medical University, Beijing, China, ³Peng Cheng Laboratory, Shenzhen, China, ⁴Mindsgo Life Science Shenzhen Co. Ltd, Shenzhen, China

[18F]-FP-DTBZ PET provides reliable information for the diagnosis of Parkinson’s disease. Quantitative analysis of PET images requires a precise segmentation of the region of interest. Two [18F]-FP-DTBZ PET image quantification methods, multi-atlas based and template based methods were compared in this study. A total of 68 subjects were included, each of them underwent 3D T1-weighted MR imaging and [18F]-FP-DTBZ PET imaging. Twenty subjects were used to build atlases and 48 were used for validation. Using dice coefficient and ICC coefficient for evaluation, we observed that the multi-atlas based method showed better performance than the template based method.

Na Zhao^1,2,3,4,5, Juan Yue^1,2,3, Zi-Jian Feng^1,2,3, Yang Qiao ^1,2,3,5,6, Li-Xia Yuan^1,2,3, Jue Wang⁷, Yong Zhang⁸, Yu-Tao Xiang ^4,5,9, and Yu-Feng Zang ^1,2,3
1Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China, Hangzhou, China, ²Institute of Psychological Sciences, Hangzhou Normal University, Hangzhou, China, Hangzhou, China, ³Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, China, Hangzhou, China, ⁴Unit of Psychiatry, Department of Public Health and Medicinal Administration, & Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Macao SAR, China, Taipa, Macau, ⁵Centre for Cognitive and Brain Sciences, University of Macau, Macao SAR, China, Taipa, Macau, ⁶Faculty of Health Sciences, University of Macau, Macao SAR, China, Taipa, Macau, ⁷Institute of sports medicine and health, Chengdu Sport University, Chengdu, China, Chengdu, China, ⁸MR Research, GE Healthcare, Shanghai, China, Shanghai, China, ⁹Institute of Advanced Studies in Humanities and Social Sciences, University of Macau, Macao SAR, China, Taipa, Macau

The current study systematically investigated multiple factors that affect the reliability of the FC location and strength of the DLPFC with a few emotional related deep regions. The group-level voxel-wise FC strength reliability was low to moderate, indicating its little significance for guiding individualized rTMS treatment. In terms of the FC location reliability, the intra-individual distances of the center of gravity (COG) were 3.8-7.3 mm across different conditions, which suggest that the COG of the seed-based FC might be potential stimulation target for individualized precise rTMS treatment of affective brain disorders.