我国高场及超高场磁共振成像设备研制和市场化的机遇与挑战
Opportunities and Challenges of High-field and Ultra-high-field Magnetic Resonance Imaging in China
通讯作者: * Tel: 027-87197630, E-mail:taoch@mail.whlib.ac.cn.
收稿日期: 2024-12-30 网络出版日期: 2025-02-08
基金资助: |
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Corresponding authors: * Tel: 027-87197630, E-mail:taoch@mail.whlib.ac.cn.
Received: 2024-12-30 Online: 2025-02-08
磁共振成像(MRI)作为一种无创的高分辨医学影像技术,是临床医学诊断的利器,当前MRI不断向更高磁场强度发展.高场及超高场MRI在临床医学诊断及新兴前沿成像技术等领域上展现出明显优势,成为全球各国竞相突破的方向.高场及超高场MRI设备是科学研究和临床应用的重要保障,各国均将其作为重要战略行业予以重视和支持.本文全面分析了高场及超高场MRI设备的国内外市场格局、核心技术竞争态势,重点讨论了我国发展面临的机遇与挑战,并提出了针对性建议.
关键词:
Magnetic resonance imaging (MRI), as a non-invasive, high-resolution medical imaging technology, is a powerful tool for clinical disease diagnosis. Current MRI systems are advancing towards higher magnetic field strength. High-field (HF) and ultra-high-field (UHF) MRI have demonstrated substantial advantages in clinical diagnosis and emerging cutting-edge imaging technologies, making them a focus of global competition. HF and UHF MRI equipment serves as a fundamental guarantee for scientific research and clinical applications, and is emphasized and supported as a strategic industry in many countries. This paper comprehensively analyzes the global market landscape and core technology competition in HF and UHF MRI equipment, highlights opportunities and challenges for China’s development in this field, and proposes targeted recommendations.
Keywords:
本文引用格式
马滢雪, 赵晏强, 杨晓冬, 蒋滨, 陶诚.
MA Yingxue, ZHAO Yanqiang, YANG Xiaodong, JIANG Bin, TAO Cheng.
引言
高场及超高场MRI通过提升图像质量、加速成像速度、增强功能成像能力、提供丰富的代谢信息等,不仅显著提高了临床诊断的准确性,还推动了科学研究和个性化医疗的发展[1].其重要性不仅体现在医学领域,还具有重要的战略意义,各国纷纷投入资源进行研发和支持,以提升本国在医学影像领域的竞争力.高场及超高场MRI设备的研制及转化不仅关乎医疗设备自主化,更是抢占未来医学影像战略制高点的关键一役.目前大部分研究是关于高场及超高场MRI的技术及应用研究[2-3],缺乏对其设备的市场现状及关键技术竞争态势的全面分析.本文系统分析了高场及超高场MRI设备的国内外市场格局、核心技术竞争态势,根据我国的发展现状及机遇挑战,提出了相关建议,希望对我国相关产业的进一步发展提供参考.
1 全球高场及超高场MRI发展现状及应用前景
1.1 高场MRI和超高场MRI
磁共振成像(Magnetic Resonance Imaging,MRI)是在静磁场下,对样品施加特定频率的射频脉冲和特定方向的磁场梯度,从而产生位置依赖的磁共振信号,实现空间位置信息编码.利用图像重建技术进行解码,可以重建出样品三维图像.MRI作为一种革命性的医学诊断技术,极大地推动了医学、神经生理学和认知神经科学快速发展.
通常将磁场强度在1.5~3.0 T的设备称为高场MRI,主要产品有1.5 T和3.0 T两种;磁场强度高于3.0 T的设备称为超高场MRI,主要有5.0 T、7.0 T、9.4 T、10.5 T、11.7 T五种.其中,已经商业化的临床MRI有1.5 T、3.0 T、5.0 T和7.0 T,而9.4 T、10.5 T和11.7 T还处于科研使用阶段.高场及超高场MRI系统涉及学科交叉多、技术体系复杂,是医疗设备领域门槛最高的方向之一.
1.2 高场及超高场MRI应用前景广阔
高场及超高场MRI推动了一系列新兴前沿技术的临床研究与应用.一是血氧水平依赖(Blood Oxygenation Level Dependent,BOLD)功能MRI(Functional Magnetic Resonance Imaging,fMRI)技术. BOLD fMRI对大脑神经活动的血液动力学变化进行成像,可以间接地反映大脑的神经活动[13].在超高场系统下,BOLD的灵敏度会大幅提升[14],除了可以提高fMRI图像的质量外,还可对微脉管和微脉管系统产生的BOLD信号进行快速定量映射,以更高的时间和空间分辨率获取fMRI数据,有望提供有关神经元激活的新信息[15].二是化学交换饱和转移(Chemical Exchange Saturation Transfer,CEST)MRI成像技术.CEST MRI作为一种新型对比增强技术,通过饱和特定质子将饱和信号传给周围自由水质子,就可以检测水信号的变化来实现间接成像.该技术将传统MRI的实用性扩展到分子成像领域,自推出以来,CEST MRI已越来越多地用作不稳定质子和微环境特性成像的灵敏工具[16],以补充常规磁共振波谱或MRI检查的不足.尽管CEST MRI可以在3 T磁场强度下工作,但CEST MRI很大程度上受益于超高场,这是由于超高场的更高信噪比和光谱分辨率,可以改善z谱中不同代谢物的分离[17].在最近的研究中,超高场CEST MRI展示出了肿瘤分级和治疗效果预测的潜力[18-19].三是除传统1H核以外的其他自旋原子核(X核)MRI技术.由于超高场MRI的极高SNR增益作用,X核MRI在临床研究中也日益普及[20].例如,23Na MRI可作为软骨退变、乳腺癌治疗监测的临床研究工具[21],31P MRI和磁共振波谱可以深入了解细胞的体内能量代谢等[22]. 这些新兴前沿技术使MRI应用范围进一步拓展,未来有望实现从研究到临床诊断的飞跃.
高场及超高场MRI设备的应用前景广泛,其技术优势使其在医学影像领域具有巨大的发展潜力.然而,要将这些技术优势转化为市场中的竞争优势,需要从技术研发、市场拓展、政策支持等多方面入手.
2 国际和国内高场及超高场MRI设备市场格局
2.1 国际市场
表1 全球主要的高场及超高场MRI企业情况
Table 1
主要MRI企业 | 国家 | MRI设备主要场强 |
---|---|---|
通用电气 福纳公司 | 美国 | 1.5 T、3.0 T、7.0 T 1.5 T、3.0 T |
飞利浦 | 荷兰 | 1.5 T、3.0 T |
西门子 | 德国 | 1.5 T、3.0 T、7.0 T |
佳能医疗 日立公司 富士胶片公司 | 日本 | 1.5 T、3.0 T 1.5 T、3.0 T 1.5 T、3.0 T |
联影医疗 东软医疗 | 中国 | 1.5 T、3.0 T、5.0 T 1.5 T、准3.0 T |
2.2 国内市场
3 高场及超高场MRI设备核心技术竞争态势
MRI设备主要包括磁体、梯度系统、射频系统、计算机系统和其他辅助设备.对MRI设备核心部件研发的国内外竞争情况进行分析,具体情况见3.1小节,简要总结如表2所示.
表2 MRI设备核心部件的主要机构及国内外竞争形势
Table 2
磁共振核心部件 | 国外主要机构 | 国内主要机构 | 目前形势 |
---|---|---|---|
磁体 | 美国GE、德国西门子和布鲁克、荷兰 飞利浦、日本三菱、英国特斯拉公司、 意大利ASG超导体公司 | 宁波健信、辰光医疗、联 影医疗、东软医疗、奥泰 医疗、中国科学院电工研 究所 | 国内外差距较大,中高端 产品以进口为主 |
梯度系统 | 美国GE、德国西门子和布鲁克、荷兰 飞利浦、澳大利亚磁力公司 | 联影医疗、宁波健信、 东软医疗 | 国内外差距较大, 以进口为主 |
射频系统 | 美国Invivo、GE和美国仪器公司、荷兰 飞利浦、英国特斯拉公司和MR线圈 科技公司、德国西门子和布鲁克公司、 日本东芝 | 联影医疗、辰光医疗 | 国内外差距较大, 以进口为主 |
计算机系统 (量子计算机研发) | 美国麻省理工大学、德国斯图加特大学、荷兰代尔夫特理工大学 | 中国科学技术大学、清华 大学、南方科技大学 | 研发阶段,我国比肩美国, 处于世界一流水平 |
3.1 核心部件
3.1.1 磁体生产集中在欧美和日本
磁体是MRI重要的核心部件,占据MRI设备成本的30%至60%.高场及超高场MRI主要采用超导磁体,磁场强度越大,研发难度越大.根据日商环球讯息有限公司的全球产业分析(Global Industry Analysts)数据显示[32],2022年全球超导磁体市场估计为32亿美元,预计到2030年将达到40亿美元规模,复合年增长率为2.9%.
我国可生产MRI超导磁体的企业主要有宁波健信、辰光医疗、联影医疗、东软医疗、奥泰医疗等.宁波健信、辰光医疗、联影医疗、东软医疗可以生产3.0 T MRI磁体,7.0 T及以上超高场磁体长期被国外企业垄断.2022年,中国科学院电工研究所研制出9.4 T人体全身MRI超导磁体,打破了国外对该技术的垄断[36].
利用incopat数据库,对磁共振超导磁体专利进行检索分析(图1,检索时间为2024年1月5日),日立、GE、飞利浦、西门子等领先的影像公司拥有大量的技术专利,具有较强的自主研发实力.我国超高场磁体专利申请量最多的是中国科学院,但是我国企业专利申请相对较少,研发实力相对薄弱.
图1
图1
磁共振超导磁体专利申请数量
Fig. 1
Number of patent applications for magnetic resonance superconducting magnets
3.1.2 梯度与射频系统国内外差距大,以进口为主
射频系统负责产生射频场和接收射频信号,是MRI的关键组成部分之一,对图像的分辨率和信噪比影响非常大.射频系统作为MRI系统技术密集的核心部件,具有行业准入门槛高,研发难度大,研发周期长、成本高等技术壁垒.因此,行业内射频线圈的供给尚不能完全满足需求,并且呈现供给方集中的特点[40],主要集中在北美和欧洲.从全球来看,MRI射频线圈生产商主要包括美国Invivo公司、GE和美国仪器公司(USA Instruments)、荷兰的飞利浦、英国特斯拉公司和MR线圈科技(CoilTech)公司、德国西门子和布鲁克公司、日本东芝、中国联影医疗和辰光医疗等[37].目前西门子、GE、飞利浦等国外企业在市场中占据主导地位,国内企业主要集中在中低端市场,高端射频系统的研发和生产仍面临技术挑战[41].
3.1.3 量子计算机赋能MRI,我国科研处于一流水平
计算机系统相当于MRI仪器的“大脑”,控制着MRI的脉冲激发、信号采集、数据运算和图像显示等功能.相比经典计算机,量子计算机的强大计算能力可以带来更快、更全面的方法,从MRI中提取相关物理信息,并改善临床诊断.医学成像领域一直在寻求创新方法来实现临床定量MRI,量子计算机可以加速扫描,促进定量MRI转化为临床应用.与常规的依靠经验观察MRI图像进行定性评估不同,定量MRI通过提取图像3D像素中的信息,以可量化的参数更精准地评估人体特性.
量子计算机潜力巨大,目前还处于科研阶段.在量子计算机原型机方面,世界主要国家均有所突破,比如,美国谷歌公司推出53个量子比特的计算机“悬铃木”,中国科学技术大学团队先后研制出76光子的“九章”光量子计算原型机、113光子的“九章二号”和255光子的“九章三号”等[42];在MRI的量子算法方面,主要国家也进行科技布局,2018年5月,微软与凯斯西储大学合作,将利用量子启发算法,处理比传统计算机可行数据量更大的临床数据,以此改进MRI扫描[43].2022年7月,美国能源部费米国家加速器实验室(FNAL)超导量子材料和系统中心(SQMS)与纽约大学朗格尼健康中心合作[44],探索分析MRI扫描新方法,双方共同致力于利用量子计算加速MRI扫描.目前,在磁共振量子计算和算法研究方面,主要研究机构包括美国麻省理工大学、德国斯图加特大学、荷兰代尔夫特理工大学、中国科学技术、清华大学、南方科技大学等.
3.2 AI技术的布局
人工智能(AI)在医疗装备领域已大显身手.AI赋能的核心技术可以在MRI的图像生成及后处理、辅助疾病诊断、预后预测等诸多方面发挥重要作用,使MRI更加智能、高效和精准[45,46].AI医学影像的快速发展也为MRI设备升级及其在疾病精准诊疗中的应用带来新的机遇.国内外知名企业已布局AI技术研发,如GE的AIR™ Recon DL人工智能平台(2019),西门子的AI 2.0人机交互平台myExamCompanion平台(2020)以及Deep Resolve技术(2022),飞利浦的超级人工智能重建平台SmartSpeed(2021)和全自动工作流引擎MR Workspace(2021),联影医疗的磁共振“类脑”技术平台(2021),佳能医疗的DLR-AiCE系统(2021)等,不仅实现了扫描速度、图像信噪比和分辨率的同时提升,还可无缝集成到临床工作流程中,实现从图像采集、重建、后处理的全流程覆盖.我国在AI医疗领域发展处于国际领先地位,仅次于美国[47],截止2024年8月,我国共有相关企业536家[48],应用领域十分广泛,在影像三维重建、病灶识别与标注、靶区自动勾画等方面都有较好的研究基础[49].先进的AI影像技术、巨大的市场需求以及国家利好政策为我国AI+MRI的发展提供了“沃土”.
4 我国MRI面临的发展机遇
4.1 我国MRI市场需求巨大
我国人均MRI保有量低,有巨大缺口.按照2022年数据[50],日本人均MRI设备拥有量最多,为每百万人口约57.4台.美国、韩国每百万人口拥有量分别为34.7和34.2台,均远超我国9.4台/百万人的保有量.随着我国老年人口的增加和医疗保健服务业迅速扩张,MRI临床检查需求持续高涨.同时,随着人民生活水平提高和对更高医疗水平的需求增加,我国MRI设备将会不断升级,3.0 T有望逐步替代1.5 T. 美国《财富》2023年商业观察数据预测,未来我国将成为全球最大的MRI市场之一.
4.2 我国技术研发实力不断提升
虽然我国MRI医疗设备产业起步较晚,但是近年来我国MRI研发实力突飞猛进(图2).2008年我国奥泰医疗研制出我国首台具有核心知识产权的1.5 T MRI整机,成为国产高场超导MRI的破冰者[51],比GE推出全球首台1.5 T超导MRI设备晚了25年.但是,近15年来随着我国联影医疗、东软医疗、奥泰医疗等医疗企业开启MRI仪器的自主研发之路,我国国产MRI仪器开始崛起,国内MRI市场格局正在悄然改变.我国国产1.5 T MRI市场占有率不断增加,用户认可度也不断上升,逐步实现由弱渐强的转变.据统计,国内国产1.5 T MRI市场从2013年的不足5%上升到2022年的47%[31].2014年我国联影医疗研制出全核心技术自主知识产权的3.0 T MRI,2022年联影自主研制的5.0 T MRI获批上市,这些标志我国MRI研发技术迈上新台阶.从2022年我国1.5 T和3.0 T MRI主要企业的市场份额分析[31](图3),德国西门子、美国GE、荷兰飞利浦三大企业占据了我国将近64.7%的市场,我国本土企业市场占有率也在逐渐提高,占有率约为33.4%.其中,联影医疗的市场占有率上升至23.9%,东软医疗的市场占有率为2.4%,入围MRI国内市场占有率前五,发展空间广阔.2022年数据统计表明,联影医疗1.5 T MRI国内新增市场份额超越GPS,排名第一,3.0 T MRI新增市场份额排名第三[52],我国MRI设备国产替代空间较大.
图2
图2
我国高场及超高场MRI的发展历程
Fig. 2
The development process of high-field and ultra-high-field MRI in China
图3
图3
2022年国内高场MRI市场占比情况
Fig. 3
The share of domestic high-field MRI market in 2022
对于超高场MRI中7 T及以上MRI来说,我国尚未突破7 T MRI的商业化,但是2021年联影医疗推出了我国首台9.4 T临床前MRI,我国已跻身超高场MRI研发前列.
4.3 国家高度重视高端医疗装备研发
磁共振等医疗装备是我国卫生健康事业的重要基石,是保障人民群众生命安全和身体健康的医之重器,也是提高医疗诊断水平的重要手段.
中共中央、国务院高度重视高端医疗装备的发展,2016年10月,中共中央、国务院印发《“健康中国2030”规划纲要》,提出大力发展高性能医疗器械等,提高具有自主知识产权的医学诊疗设备的国际竞争力.2020年3月,习近平总书记发表重要讲话,强调“要加快补齐我国高端医疗装备短板,加快关键核心技术攻关,突破这些技术装备瓶颈,实现高端医疗装备自主可控”.2021年3月,国家“十四五”规划提出将高端医疗设备作为重点发展领域之一,“研制高端医学影像等大型医疗设备及关键零件”.2022年4月,国务院办公厅印发《“十四五”国民健康规划》提出,做优做强健康产业,开展原创性技术攻关,推出一批融合人工智能等新技术的高质量医疗装备.
国家相关部门也相继在规划中布局磁共振研发.2017年5月,科技部印发《“十三五”医疗器械科技创新专项规划》,提出加快发展MRI,重点开发与国外主流产品技术水平相当的高场(不小于3 T)超导MRI系统.2021年12月,工业和信息化部联合十部委印发《“十四五”医疗装备产业发展规划》强化关键核心技术攻关,重点发展新型医学影像等领域的医疗器械,支持企业围绕医疗器械生产的关键技术、核心装备、新型材料开展攻关.《国家自然科学基金“十四五”发展规划》优先支持基于人工智能的医学影像等智能化医疗的基础理论与关键技术,推进医学诊疗核心技术突破.
党中央、国务院的决策部署,国家有关部门的规划布局为我国高场及超高场高端磁共振医疗设备的快速发展提供了有力的指导和保障.
5 关于未来的发展建议
我国高场及超高场MRI在政策和市场需求的驱动下,迎来了快速发展的良好机遇.建议未来从加大政策支持、提升关键核心技术能力、提升产品竞争力等方面加强布局.
5.1 增强国产MRI的市场竞争力
我国企业应改变市场对于进口医疗设备先入为主的看法,提升国产MRI产品性价比及售后服务,提升技术水平和产品性能在医疗机构的认可度,建立良好的业界口碑和影响力.政府通过政策支持国产MRI企业加强自主研发能力、优先采购国产MRI产品,提升国产产品市场占有率.
5.2 提高核心零部件生产能力,突破技术瓶颈
我国MRI医疗装备产业已进入快速、高质量发展期,当前最重要的是确保整个产业链供应链的自主可控能力,在关键时刻“不掉链子”,摆脱国外产品及技术垄断.目前国内MRI核心元件(如磁体、射频系统、梯度系统等)竞争能力落后于国际先进水平,元器件生产商技术升级速度赶不上整机生产商研发速度,仍存在国内自主知识产权的MRI整机需要使用进口元器件的窘境.在国外技术垄断局势和国内政策的驱使下,我国核心元件厂商要加大自身研发能力,加强高端磁体、梯度与射频系统的研发和生产,并与研发实力较强的国家科研机构(如高端磁体研制可与中国科学院电工研究所合作)、高校合作,依托已有的科研平台及技术加快推进高场及超高场MRI核心零部件的研发及产业化,着力突破技术瓶颈.
5.3 加大高端产品的研发及产业化实力
对于超高场MRI等高端产品,我国竞争力与世界一流水平相比还存在明显差距.我国MRI企业、科研院所、高校等先进技术研发主力军应加大研发力度,加快我国超高场MRI的研发及科技成果转化进程,加强量子、AI技术与MRI的融合.另外,密切关注产业发展动向,根据自身优势前瞻布局新兴研究方向,掌握高端MRI产业发展主动权.比如,中国科学院在多核和超极化磁共振领域具有很大的技术优势[53],国内相关企业可与中国科学院开展合作,产学研结合,优势互补,开发多核或者超极化高场超高场MRI,在该赛道上争先突破.
利益冲突
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