1
|
Zhao Y, Bhosale AA, Zhang X. Multimodal surface coils for low field MR imaging. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.04.14.24305802. [PMID: 38699318 PMCID: PMC11065021 DOI: 10.1101/2024.04.14.24305802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
Low field MRI is safer and more cost effective than the high field MRI. One of the inherent problems of low field MRI is its low signal-to-noise ratio or sensitivity. In this work, we introduce a multimodal surface coil technique for signal excitation and reception to improve the RF magnetic field (B 1 ) efficiency and potentially improve MR sensitivity. The proposed multimodal surface coil consists of multiple identical resonators that are electromagnetically coupled to form a multimodal resonator. The field distribution of its lowest frequency mode is suitable for MR imaging applications. The prototype multimodal surface coils are built, and the performance is investigated and validated through numerical simulation, standard RF measurements and tests, and comparison with the conventional surface coil at low fields. Our results show that the B 1 efficiency of the multimodal surface coil outperforms that of the conventional surface coil which is known to offer the highest B 1 efficiency among all coil categories, i.e., volume coil, half-volume coil and surface coil. In addition, in low-field MRI, the required low-frequency coils often use large value capacitance to achieve the low resonant frequency which makes frequency tuning difficult. The proposed multimodal surface coil can be conveniently tuned to the required low frequency for low-field MRI with significantly reduced capacitance value, demonstrating excellent low-frequency operation capability over the conventional surface coil.
Collapse
|
2
|
Meng Y, Mo Z, Hao J, Peng Y, Yan H, Mu J, Ma D, Zhang X, Li Y. High-resolution intravascular magnetic resonance imaging of the coronary artery wall at 3.0 Tesla: toward evaluation of atherosclerotic plaque vulnerability. Quant Imaging Med Surg 2021; 11:4522-4529. [PMID: 34737920 DOI: 10.21037/qims-21-286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 07/05/2021] [Indexed: 11/06/2022]
Abstract
Background To validate the feasibility of generating high-resolution intravascular 3.0 Tesla (T) magnetic resonance imaging of the coronary artery wall to further plaque imaging. Methods A receive-only 0.014-inch diameter magnetic resonance imaging guidewire (MRIG) was manufactured for intravascular imaging within a phantom experiment and the coronary artery wall of the swine. For coronary artery wall imaging, both high-resolution images and conventional resolution images were acquired. A 16-channel commercial surface coil for magnetic resonance imaging was employed for the control group. Results For the phantom experiment, the MRIG showed a higher signal-to-noise ratio than the surface coil. The peak signal-to-noise ratio of the MRIG and the surface coil-generated imaging were 213.6 and 19.8, respectively. The signal-to-noise ratio decreased rapidly as the distance from the MRIG increased. For the coronary artery wall experiment, the vessel wall imaging by the MRIG could be identified clearly, whereas the vessel wall imaging by the surface coil was blurred. The average signal-to-noise ratio of the artery wall was 21.1±5.40 by the MRIG compared to 8.4±2.19 by the surface coil, where the resolution was set at 0.2 mm × 0.2 mm × 2 mm. As expected, the high-resolution sequence clearly showed more details than the conventional resolution sequence set at 0.7 mm × 0.7 mm × 2.0 mm. Histological examination showed no evidence of mechanical injuries in the target vessel walls. Conclusions The study validated the feasibility of generating magnetic resonance imaging (MRI) at 0.2 mm × 0.2 mm × 2 mm for the coronary artery wall using a 0.014 inch MRIG.
Collapse
Affiliation(s)
- Yanfeng Meng
- Department of MRI, Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, China
| | - Zhiguang Mo
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,The Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province, Shenzhen, China
| | - Jinying Hao
- Department of MRI, Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, China
| | - Yueyou Peng
- Department of MRI, Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, China
| | - Hui Yan
- Department of MRI, Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, China
| | - Jingbo Mu
- Department of Cardiology, Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, China
| | - Dengfeng Ma
- Department of Cardiology, Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, China
| | - Xiaoliang Zhang
- Department of Biomedical Engineering, State University of New York at Buffalo, NY, USA
| | - Ye Li
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,The Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province, Shenzhen, China
| |
Collapse
|
3
|
Wáng YXJ, Gong JS, Loffroy R. On pancreatic cancer screening by magnetic resonance imaging with the recent evidence by Del Chiaro and colleagues. Chin J Cancer Res 2015; 27:417-22. [PMID: 26361411 DOI: 10.3978/j.issn.1000-9604.2015.06.09] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 06/12/2015] [Indexed: 12/12/2022] Open
Affiliation(s)
- Yì-Xiáng J Wáng
- 1 Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China ; 2 Department of Radiology, Shenzhen People's Hospital, Second Clinical Medicine College of Jinan University, Shenzhen 518020, China ; 3 Department of Vascular, Oncologic and Interventional Radiology, Le2i UMR CNRS 6306, University of Dijon School of Medicine, Bocage Teaching Hospital, Dijon Cedex, France
| | - Jing-Shan Gong
- 1 Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China ; 2 Department of Radiology, Shenzhen People's Hospital, Second Clinical Medicine College of Jinan University, Shenzhen 518020, China ; 3 Department of Vascular, Oncologic and Interventional Radiology, Le2i UMR CNRS 6306, University of Dijon School of Medicine, Bocage Teaching Hospital, Dijon Cedex, France
| | - Romaric Loffroy
- 1 Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China ; 2 Department of Radiology, Shenzhen People's Hospital, Second Clinical Medicine College of Jinan University, Shenzhen 518020, China ; 3 Department of Vascular, Oncologic and Interventional Radiology, Le2i UMR CNRS 6306, University of Dijon School of Medicine, Bocage Teaching Hospital, Dijon Cedex, France
| |
Collapse
|
4
|
Wang YXJ, Gong JS, Suzuki K, Morcos SK. Evidence based imaging strategies for solitary pulmonary nodule. J Thorac Dis 2014; 6:872-87. [PMID: 25093083 DOI: 10.3978/j.issn.2072-1439.2014.07.26] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 06/29/2014] [Indexed: 12/21/2022]
Abstract
Solitary pulmonary nodule (SPN) is defined as a rounded opacity ≤3 cm in diameter surrounded by lung parenchyma. The majority of smokers who undergo thin-section CT have SPNs, most of which are smaller than 7 mm. In the past, multiple follow-up examinations over a two-year period, including CT follow-up at 3, 6, 12, 18, and 24 months, were recommended when such nodules are detected incidentally. This policy increases radiation burden for the affected population. Nodule features such as shape, edge characteristics, cavitation, and location have not yet been found to be accurate for distinguishing benign from malignant nodules. When SPN is considered to be indeterminate in the initial exam, the risk factor of the patients should be evaluated, which includes patients' age and smoking history. The 2005 Fleischner Society guideline stated that at least 99% of all nodules 4 mm or smaller are benign; when nodule is 5-9 mm in diameter, the best strategy is surveillance. The timing of these control examinations varies according to the nodule size (4-6, or 6-8 mm) and the type of patients, specifically at low or high risk of malignancy concerned. Noncalcified nodules larger than 8 mm diameter bear a substantial risk of malignancy, additional options such as contrast material-enhanced CT, positron emission tomography (PET), percutaneous needle biopsy, and thoracoscopic resection or videoassisted thoracoscopic resection should be considered.
Collapse
Affiliation(s)
- Yi-Xiang J Wang
- 1 Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China ; 2 Department of Radiology, Shenzhen People's Hospital, Jinan University Second Clinical Medicine College, Shenzhen 518020, China ; 3 Department of Radiology, The University of Chicago, Chicago, IL 60637, USA ; 4 Diagnostic Imaging, The University of Sheffield, Sheffield, UK
| | - Jing-Shan Gong
- 1 Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China ; 2 Department of Radiology, Shenzhen People's Hospital, Jinan University Second Clinical Medicine College, Shenzhen 518020, China ; 3 Department of Radiology, The University of Chicago, Chicago, IL 60637, USA ; 4 Diagnostic Imaging, The University of Sheffield, Sheffield, UK
| | - Kenji Suzuki
- 1 Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China ; 2 Department of Radiology, Shenzhen People's Hospital, Jinan University Second Clinical Medicine College, Shenzhen 518020, China ; 3 Department of Radiology, The University of Chicago, Chicago, IL 60637, USA ; 4 Diagnostic Imaging, The University of Sheffield, Sheffield, UK
| | - Sameh K Morcos
- 1 Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China ; 2 Department of Radiology, Shenzhen People's Hospital, Jinan University Second Clinical Medicine College, Shenzhen 518020, China ; 3 Department of Radiology, The University of Chicago, Chicago, IL 60637, USA ; 4 Diagnostic Imaging, The University of Sheffield, Sheffield, UK
| |
Collapse
|