磁共振原理和临床应用（三）

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,半月板的MRI检查,半月板损伤的MRI检查,半月板损伤的MRI检查,原始神经外胚叶肿瘤,股骨头无菌坏死,MRI的临床应用-,胸部和心血管,清晰显示纵隔内的病变和肺内病变纵隔内侵犯，以及胸壁病变,对肺内病变显示不如CT，肺内弥漫性病变和钙化病变不能显示,能显示心脏的形态和功能改变，同时能显示冠状动脉和心肌个塞梗死,清晰显示大血管病变，如动脉瘤，夹层,肺癌,胸腺瘤,心脏和心梗,夹层动脉瘤,主动脉缩窄,Cardiac Function:FIESTA-CINE,10 sec breath-hold,Full R-R coverage,High temporal resolution,short TR and TE,Up to 60 cine movies viewed simultaneously with Multi-Cine Tool,FIESTA,Fast Imaging Employing,Steady-sTate Acquisition,10 sec breath-hold,full R-R coverage,FASTCINE,FIESTA-CINE,diastole,systole,FIESTA,Fast Imaging Employing Steady State Acquisition,10 sec breath-hold,Full R-R coverage,High temporal resolution,short TR and TE,FIESTA,Fast Imaging Employing,Steady-sTate Acquisition,Cardiac Function:FIESTA-CINE,17 sec breath-hold,full R-R coverage,60 cardiac phase,FIESTA,CINE Imaging with up to 60 Phases per Breath-hold,FIESTA-CINE vs.FASTCINE.,FASTCINE,FIESTA-CINE,four chamber,view,short axis,view,FIESTA-CINE vs.FASTCINE.,FASTCINE,FIESTA-CINE,long axis views,short axis view,2D Breath-held spiral,2D Non-breath-held spiral with NAV correction,2D Vessel-Tracked,Fastcard,&Spiral,3D Non-breath-held with NAV correction,A Family of Techniques,Image courtesy of,Dr.Vince Ho,Uniformed Services University of the Health Sciences,(USUHS)/National Naval Medical Center(NNMC)Bethesda,MD,NIH Radiology,Bethesda,MD,Coronary MRA-Breath-held Spiral Technique,Breath-held(18 sec),2D slice(5mm),Non-contrast enhanced,20 X 4096 matrix,0.52 mm/pixel resolution,High Resolution Spiral MRA,Coronary MRA-High Resolution Spiral Imaging,Coronary MRA-High Resolution 3D Spiral Imaging,RCA-.8mm pixel resolution,LCA-.8mm pixel resolution,MRI的临床应用-,腹部,肝脏：对小的囊肿、血管瘤和肿瘤，MR 优于CT扫描，组织特异造影剂应用提高了肝脏病变的诊断,胰腺：对胰腺病变到达同CT的水平,肾脏、肾上腺：肾血管狭窄优于常规CT，占位病变与CT扫描相同,MRCP优于CT,肝癌,肝转移瘤,肝血管瘤,肝脂肪瘤,胰腺癌,肾血管平滑肌脂肪瘤,肾癌,肾上腺腺瘤,MR水成像,MRCP、MRU,MR水成像,MRCP、MRU可以清晰显示胆道系统和泌尿系统，具有无损伤、不需造影剂、检查方便快速、病人无痛苦、多平面显示等优点,MRCP、MRU不仅可以显示胆道和泌尿系统官腔内的病变，同时可以显示腔外的病变，能够对病灶更准确的诊断和评价。,MR胰胆管造影(MRCP),MRCP,ERCP,结石,结石,MR胰胆管造影(MRCP)-胆囊结石,MR胰胆管造影(MRCP)-胆囊结石,MR胰胆管造影(MRCP)-胆总管结石,MRCP,ERCP,结石,结石,MR泌尿系造影(MRU),双肾盂输尿管畸形并输尿管下端结石,MR泌尿系造影(MRU)-输尿管结石,结石,MR泌尿系造影(MRU)-神经性膀胱,MRI的临床应用-,盆腔,能清晰显示子宫各层结构，对子宫病变明显优于CT,对前列腺的信号改变敏感性优于CT，对前列腺癌的敏感性优于CT,对膀胱、卵巢和周围比病变也有较高诊断价值,前列腺癌,前列腺癌,子宫内膜癌,子宫内膜 异位症,参与和影响MRI成像的因素,组织固有参数,质子密度,组织T1弛豫时间,组织T2弛豫时间,血管流空效应,血流流入增强,运动和伪影,人为机器因素,外磁场强度,TR时间,TE时间,鼓励取样次数,矩阵、扫描野、扫描层厚和间隔,造影剂,磁共振成像的优点和缺点与CT的比较,优点：,软组织比照度高,无骨伪影,无生物性损伤,多方位多角度成像,流空效应和MR血管造影,功能成像,具有向组织学和分子水平开展的诊断潜能,MRI造影剂更平安,缺点：,扫描时间长,检查费用相对高,对骨和钙化不敏感,禁忌症多,空间分辨率相对低,伪影较多,MRI检查的禁忌症,装有心脏起搏器、颅内神经刺激器、耳蜗植入物、疑有眼球内金属异物和动脉瘤金属夹夹闭术后的患者严禁做MRI检查,以下患者应慎重相对禁忌：孕妇、幽禁恐怖综合症患者、生命体征不稳和不合作患者,