Ying Liu¹, Xianfu Meng^2,3, and He Wang^1,4
1Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China, ²Department of Materials Science and State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, China, ³Department of Medical Ultrasound, Shanghai Tenth People’s Hospital, School of Medicine, Tongji University, Tongji University Cancer Center, Shanghai, China, ⁴Human Phenome Institute, Fudan University, Shanghai, China

Detecting dopamine in vivo is critical for understanding many neurologic and psychiatric disorders. In this work, we developed a paramagnetic CEST-MRI method for dopamine detection using NaHoF₄@DBA nanoparticles. Our results showed that the dopamine in mouse brain can be selectively enriched in the surface of the nanoparticles and detected by CEST-MRI. Moreover, we found that the magnitude of ST% map reflecting dopamine levels in the brain of SZ mice was relatively higher than that of PD mice. 

Ibrahim Khormi^1,2,3, Oun Al-iedani^1,2, Bryan Paton^2,4, Jeannette Lechner-Scott ^2,5,6, Abdulaziz Alshehri^1,2, Amir Fazlollahi^7,8, Stefano Casagranda⁹, Christos Papageorgakis⁹, Margarita Arango-Lievano⁹, Anne-Louise Ponsonby^10,11, Patrick Liebig¹², and Saadallah Ramadan^1,2
1School of Health Sciences, University of Newcastle, Newcastle, Australia, ²Hunter Medical Research Institute, Newcastle, Australia, ³College of Applied Medical Sciences, University of Jeddah, Jeddah, Saudi Arabia, ⁴School of Psychology, University of Newcastle, Newcastle, Australia, ⁵School of Medicine and Public Health, University of Newcastle, Newcastle, Australia, ⁶Department of Neurology, John Hunter Hospital, New Lambton Heights, Australia, ⁷CSIRO Health and Biosecurity, Brisbane, Australia, ⁸Queensland Brain Institute, The University of Queensland, Brisbane, Australia, ⁹Olea Medical, La Ciotat, France, ¹⁰The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia, ¹¹Murdoch Children's Research Institute, Royal Children's Hospital, University of Melbourne, Melbourne, Australia, ¹²Siemens Healthcare GmbH, Erlangen, Germany

This novel study explores amide proton transfer weighted (APTw) imaging in people with relapsing-remitting multiple sclerosis (pw-RRMS). We evaluated the APTw signal intensity in selected MS lesions and normal-appearing white matter (NAMW) regions in 9 pw-RRMS. Compared to NAWM regions, a statistically significant increase in APTw signal intensity was observed in the MS lesions. Elevated APTw signal intensity could mark increased mobile myelin proteins decomposition and accumulation from the demyelination process.

 
 

Zhichao Wang¹, Jilei Zhang², Yu Zhao³, Ting Hua⁴, Guangyu Tang⁴, Jianqi Li⁵, and Yu Zhang^1
1Research Center for Healthcare Data Science, Zhejiang Lab, Hangzhou, Zhejiang, China, ²Philips Healthcare, Shanghai, China, ³Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, ⁴Renji Hospital affiliated to Shanghai Jiao Tong University Medical College, Shanghai, China, ⁵Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, Shanghai, China

Chemical exchange saturation transfer (CEST) imaging shows great potentials in the diagnosis of brain diseases. However, there are still many challenges in the hepatic disease due to the fat suppression and large B₀ inhomogeneity. In this study, we achieved CEST imaging with simultaneous B₀ correction in one sequence, and conducted a pixel-by-pixel prediction on the background reference Z-spectra representing the magnetization transfer and direct saturation effects. Our approach also effectively separated the amide proton transfer (APT) effects from the mixing effect of fat and nuclear Overhauser enhancement (NOE), by subtracting the background reference Z-spectra from the predicted Z-spectra.

Rohith Saai Pemmasani Prabakaran¹, Zilin Chen², Joseph H.C. Lai², Se Weon Park^1,2, Yang Liu^1,2, Jianpan Huang², and Kannie W.Y. Chan^1,2,3,4
1Hong Kong Centre For Cerebro-Cardiovascular Health Engineering, Hong Kong, Hong Kong, ²Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, Hong Kong, ³Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States, ⁴City University of Hong Kong Shenzhen Research Institute, Shenzhen, China

CEST MRI is an unique molecular imaging approach to reveal the exchangeable proton information related to physiology and pathology. However, long scanning time has hindered its translation into clinics. While deep-learning based super-resolution methods have been explored to reduce scanning time in conventional MRI, adaptation of these methods to CEST MRI has been limited due to lack of large public CEST datasets. Therefore, this study proposes two transfer learning based super-resolution methods, Single-Offset UNet and Multi-Offset UNet, for accelerating CEST MRI acquisition by using public MRI databases for pretraining and a very small CEST dataset for training.

Yin Wu¹, Zhou Liu^1,2, Qian Yang², Liyan Zou², Fan Zhang², Long Qian³, Xin Liu¹, Hairong Zheng¹, Dehong Luo², and Phillip Zhe Sun^4
1Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, ²National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, China, ³GE Healthcare, Beijing, China, ⁴Emory University School of Medicine, Atlanta, GA, United States

APT MRI scans are often performed under non-equilibrium conditions, confounding imaging quantification and tissue characterization. This study proposed a quasi-steady-state (QUASS) algorithm for fast and accurate tumor APT imaging. Seven healthy volunteers and nineteen tumor patients were scanned at 3T, with two representative RF saturation times (Ts) and relaxation delays (Td). The routine APT measures significantly varied with Ts and Td (P<.001) and were significantly smaller than the corresponding QUASS indices (P<.001). In contrast, QUASS reconstruction results showed little dependence on scan protocols (P>.05). The QUASS algorithm enables robust APT imaging, promising to expedite and standardize clinical APT tumor MRI.

Ying Liu¹, Botao Zhao¹, and Xiao-Yong Zhang^1
1Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China

The identification of the isocitrate dehydrogenase mutant (IDH_MUT) glioma and IDH wild-type (IDH_WT) glioma has significant diagnostic, prognostic, and therapeutic implications. In this work, we evaluated the non-invasive prediction of IDH mutation status in glioma mice by employing a combination of high spectral resolution CEST MRI at 11.7T together with data analysis using machine learning approaches. We demonstrated that in vivo CEST signals correspond very well with glioma genotypes. Among several CEST signals, the signals at Δω =3.5 ppm may serve as the major indicator to differentiate the IDH genotype glioma from other types.

Hao Yu¹, Yanting Wang¹, Zhanguo Sun², Weiwei Wang¹, Zhe Zhou¹, Weiqiang Dou³, Zhibo Wen⁴, and Yueqin Chen^2
1Radiology, Affiliated Hospital of Jining Medical University, Jining, China, ²Affiliated Hospital of Jining Medical University, Jining, China, ³GE Healthcare MR Research, Beijing, China, ⁴Zhujiang Hospital, Guangzhou, China

Stiffness of meningioma is an important factor affecting the surgical resection. In this study we aimed to explore if amide proton transfer-weighted MR imaging has clinical potential of predicting meningioma stiffness

Fang Wang¹, Yun Xu¹, Yong-Sheng Xiang¹, Peng Wu², Ai-Jun Shen¹, and Pei-Jun Wang^1
1Tongji Hospital, School of Medicine, Tongji University, Shanghai, China, ²Philips Healthcare, Shanghai, China

Amide proton transfer (APT) imaging is an emerging chemical exchange saturation transfer (CEST)-based MRI technique that is sensitive to mobile proteins and peptides in tissue and has drawn considerable attention in the field of cellular and molecular imaging. In the present work, our result demonstrates that it is feasible to use APT imaging for Bladder Cancer (BCa) and it has shown great potential for bladder cancer imaging, thus opening new research avenues in this field. 

Nan Meng¹, Fangfang Fu², Zhun Huang³, Ziqiang Li⁴, Yu Luo¹, Pengyang Feng³, Yaping Wu², Jianmin Yuan⁵, Yang Yang⁶, and Meiyun Wang*^1
1Department of Medical Imaging, Zhengzhou University People’s Hospital & Henan Provincial People’s Hospital, Zhengzhou, China, ²Department of Medical Imaging, Henan Provincial People’s Hospital, Zhengzhou, China, ³Department of Medical Imaging, Henan University People’s Hospital & Henan Provincial People’s Hospital, Zhengzhou, China, ⁴Department of Medical Imaging, Xinxiang Medical University Henan Provincial People’s Hospital, Zhengzhou, China, ⁵Central Research Institute, UIH Group, Shanghai, China, ⁶Beijing United Imaging Research Institute of Intelligent Imaging, UIH Group, Beijing, China

¹⁸F-Fluorodeoxyglucose positron-emission tomography/magnetic resonance imaging (¹⁸F-FDG PET/MRI) allows multimodal quantitative MRI sequences to be scanned in parallel with PET imaging, providing a more multidimensional reflection of lesion information. Our results showed that intravoxel incoherent motion (IVIM), amide proton transfer-weighted imaging (APTWI), and metabolism related parameters can be beneficial for the non-invasive assessment of PD-L1 expression in NSCLC patients, and the combination of SUV_max, D, and MTRasym(3.5ppm) may serve as a prognostic biomarker to guide immunotherapy. 

Yurui QIAN¹, Jian Hou¹, Baiyan Jiang^1,2, Vincent Wai-Sun Wong³, Queenie Chan⁴, Yixiang Wang¹, Winnie Chiu-Wing Chu¹, and Weitian Chen^1
1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Hong Kong, Hong Kong, ²Illuminatio Medical Technology Limited, Hong Kong, Hong Kong, ³Medicine & Therapeutics, The Chinese University of Hong Kong, Hong Kong, Hong Kong, ⁴Philips Healthcare, Hong Kong, Hong Kong

Spin-lock T1rho is a non-invasive MR imaging method. It has the potentials for the assessment of chronic liver diseases. However, liver iron content can potentially confound T1rho quantification of the liver. In this work, we reported a method to correct the influence of liver iron content on T1rho quantification of the liver at 3.0T.

Jian Hou¹, Yurui Qian¹, Baiyan Jiang^1,2, Queenie Chan³, Zhigang Wu⁴, Vincent Wai-Sun Wong⁵, Dimitrios Karampinos⁶, Winnie Chiu-Wing Chu¹, and Weitian Chen^1
1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Hong Kong, Hong Kong, ²Illuminatio Medical Technology Limited, Hong Kong, Hong Kong, ³Philips Healthcare, Hong Kong, Hong Kong, ⁴Philips Healthcare, Shenzhen, China, ⁵Department of Medicine & Therapeutics, The Chinese University of Hong Kong, Hong Kong, Hong Kong, ⁶Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany

Chronic liver disease is a major healthcare problem worldwide. Liver fibrosis and fat fraction are two main features of chronic liver diseases. Recent work reported that macromolecular proton fraction (MPF) mapping has potential for diagnosis of liver fibrosis. In this work, we reported a novel technique to quantify MPF and fat fraction of the liver simultaneously in a brief breath hold.

Xinying Ren¹, Diaohan Xiong¹, Tiejun Gan¹, Pengfei Wang¹, Rui Wang¹, Tao Wen¹, Yujing Li¹, Jing Zhang¹, and Kai Ai^2
1Lanzhou University Second Hospital, Lanzhou, China, ²Philips Healthcare, Xi'an, China

This study aims to analyze the metabolic information in both tumor solid and peritumoral area of gliomas to predict its genotype by using Amide Proton Transfer weighted (APTw) imaging. As a complementary method of pathological evaluation, APTw based MRI technique could provide a prediction of the gliomas genotype. Unlike other studies focus on tumor core region, our research investigated the APT_mean value of tumor solid and the peritumoral area. Interestingly, the results showed that the AUC value of peritumoral area was higher than the tumor solid. The APTw images may serve as a potential marker for the genotyping of gliomas.

Long Xiao¹, Yu Li¹, Sha Li¹, Yaping Yuan¹, Lei Zhang¹, Shizhen Chen¹, 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

We designed and synthesized a molecular probe-based on fluorescence imaging and ¹⁹F MRI bimodal imaging to identify overexpressed nitroreductase in hypoxic tumor. The two imaging modes complement each other in sensitivity and imaging depth, providing more abundant information. More importantly, the bimodal molecular probe is enriched in the tumor region depending on the passive targeting ability and has been well verified by fluorescence imaging and ¹⁹F MRI in the metastatic tumor model. And we successfully identified the cancerous left lung and healthy right lung in lung cancer model mouse.

Moyoko Tomiyasu¹, Yasuka Sahara¹, Etsuko Mitsui¹, Hiroki Tsuchiya², Takamasa Maeda², Nobuhiro Tomoyori³, Makoto Kawashima³, Tatsuya Higashi¹, Atsushi Mizota³, Kohsuke Kudo⁴, and Takayuki Obata^1
1Department of Molecular Imaging and Theranostics, National Institutes for Quantum Science and Technology, Ciba, Japan, ²Department of Medical Technology, National Institutes for Quantum Science and Technology, Ciba, Japan, ³Department of ophthalmology, Teikyo University, Tokyo, Japan, ⁴Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Japan

 We observed the movement of ¹⁷O-labelled water (H₂¹⁷O) in the eyes of three volunteers using dynamic T2W ¹H-MRI (3T). After a drop of H₂¹⁷O saline in the right eye, the signal intensity in the right anterior chamber decreased, reaching a minimum at 7–9 min, and then gradually recovered to close to that seen before the eye drop, by about 40 min. Signal decrease and recovery was also observed in the posterior chamber, but not in the vitreous body. These results show that H₂¹⁷O drops flow smoothly into the human anterior chamber and flow out slowly.

Ho Chi Joseph Lai¹, Tian Yang², Jianpan Huang¹, Yang Liu¹, Youngjin Lee², and Wai Yan Kannie Chan^1,3,4,5
1Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, Hong Kong, ²Department of Neuroscience, City University of Hong Kong, Hong Kong, Hong Kong, ³Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States, ⁴City University of Hong Kong Shenzhen Research Institute, Shenzhen, China, ⁵Hong Kong Centre for Cerebro-Cardiovascular Health Engineering, Hong Kong, Hong Kong

We have shown that CEST (APTw and rNOE) contrast demonstrated distinctive changes of ICH mouse brains longitudinally¹. As demonstrated by our published work², the rNOE changes could be primarily associated with changes in myelin. Here, we studied the APTw and rNOE contrast after ICH up to 14 days, and under DFX treatment. We observed regional changes of APTw and rNOE contrast in the core and peri-hematoma regions, especially the significant difference (P<0.05) on day 3 with and without DFX treatment. Our immunohistochemistry data indicated that rNOE contrast correlated with myelin, which supports that rNOE could detect myelin pathology during ICH.