心脏磁共振显像和X线左室造影测定左室功能的对比研究

目的评价心脏磁共振显像(MRI)和X线左室造影(LVG)检测左室(LV)功能的应用价值。方法52例患者同期均行MRI及LVG检查,测定LV舒张末期容积(EDV)、收缩末期容积(ESV)和射血分数(EF),分组比较,行相关性及一致性分析。结果MRI与LVG所测EDV、ESV、EF的相关系数分别为0.94,0.96,0.96(均P<0.001)。心肌梗死(MI)组MRI与LVG的相关系数分别为0.92,0.98,0.95(均P<0.001),一致性范围分别为(-22.4±32.4)ml,(-8.3±27.8)ml,(-2.5±8.6)%。非心肌梗死(N-MI)组MRI与LVG的相关系数分别为0.9 5,0.9 5,0.9 8(均P<0.0 0 1);一致性范围分别为(-16.2±25.5)ml,(-1.8±25.1)ml,(-1.4±8.3)%。结论MRI检测心功能准确、可靠,与LVG相关性明显,一致性好。     

磁共振心脏成像与超声心动图评价左室功能

目的:评价磁共振心脏成像(cMRI)与超声心动图(Echo)对左室功能的诊断价值。方法:心肌梗死患者30例,分别行cMRI及Echo检查,比较2种方法测量所得心功能指标,包括左室射血分数(EF)、每搏输出量(SV)和心输出量(CO)。结果:cMRI测得左室射血分数、每搏输出量、心输出量明显低于Echo检测值,差异有统计学意义(P<0.05)。结论:对左室整体功能的评价,心脏MRI与超声心动图均具重要的临床应用价值,但cMRI检测心功能更准确、可靠。     

胎儿胸腔异常心脏位置的产前磁共振成像诊断

目的探讨产前磁共振成像(MRI)在胎儿胸腔异常心脏位置诊断中的应用价值。方法 57例孕妇,孕龄20～36周。产前常规行超声检查后24～48 h内行MRI检查,采用二维快速平衡稳态采集(2D FIESTA)序列、单次激发快速自旋回波(SSFSE)序列、快速反转恢复运动抑制(FIRM)序列以及动态FIESTA序列,行胎儿颅脑、胸部腹部常规及胸部(肺、心脏)重点冠状面、矢状面及横断面扫描,将产前MRI、超声表现与出生后影像表现或手术(n=49)、引产后尸体解剖结果(n=8)对照。结果原发性心脏位置异常即右位心5例;继发性心脏位置异常52例,其中右肺发育不良7例、先天性膈疝(CDH)18例、先天性肺囊腺瘤样畸形(CCAM)24例、支气管肺隔离症(BPS)2例和纵隔占位1例。结论 MRI各序列综合应用在胎儿胸腔异常心脏位置及病因诊断方面具有一定的应用价值;FIESTA序列同一切面能同时显示异常心脏位置和导致其异常的胸部其他病变,动态FIESTA序列能动态显示较明显的心脏血流异常;SSFSE和FIRM序列能较好显示引起心脏位置异常的其他胸部病变。     

大脑胶质瘤病的磁共振及磁共振波谱诊断价值

目的探讨磁共振成像(MRI)和磁共振波谱成像(MRS)对大脑胶质瘤病的诊断价值。方法对13例经手术或活组织病理检查证实的大脑胶质瘤病患者的临床表现及MRI平扫、增强、MRS影像学资料进行回顾性分析。MRI常规行T1加权像(T1WI)、T2加权像(T2WI)及液体衰减反转恢复序列(FLAIR),采用时间飞跃法(TOF)的磁共振血管成像(MRA)、T1WI增强扫描。氢质子MRS采用单体素激励回波探测法(STEAM),并分析N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱复合物(Cho)等物质峰值改变。结果所有病例均侵犯2个或2个以上脑叶,以颞叶、枕叶、胼胝体、基底节和丘脑等部位侵犯受累常见。病变区T1WI呈低或等信号、T2WI呈高或混杂高信号、液体衰减反转恢复序列上为高信号,未见明显坏死、钙化,受累区域脑组织肿胀,占位效应轻。注射钆喷酸葡胺增强扫描示,9例无明显强化,2例斑片状强化,1例结节状强化,1例线状轻度强化。病变区域MRS表现为不同程度NAA降低,NAA/Cr比值降低;Cho上升,Cho/Cr和Cho/NAA比值上升。结论 MRI结合MRS对大脑胶质瘤病的诊断及鉴别诊断具有较大临床价值,是目前诊断大脑胶质瘤病的首选影像学方法。     

术中磁共振成像技术用于神经外科手术的麻醉处理

目的探讨术中磁共振成像技术用于神经外科手术的围术期麻醉处理理特点。方法 30例颅内肿瘤患者术前经过安全筛查,采用磁兼容的麻醉机、监护仪及输注泵系统,在气管插管静吸复合麻醉下行术中磁共振成像开颅肿瘤切除术。记录患者手术时间、术中磁共振成像次数、成像时间、成像相关时间(即从成像准备工作开始至重新开始手术的时间)、因磁共振成像延长的时间、首次磁共振成像前后体温变化和围术期与麻醉、成像相关的意外及并发症。结果 30例患者均顺利完成手术,手术时间为9.33±2.82 h,平均成像次数为1.8次(1~6次),每次成像时间为29.24±10.10 min,成像相关时间为43.83±10.23 min,手术延长时间为92.63±28.31 min。首次成像后2 h体温显著高于麻醉诱导后。围术期未发生与成像及麻醉相关的意外及并发症。结论除遵循一般神经外科麻醉的处理原则外,麻醉医生需针对术中磁共振成像的特殊环境及特殊过程,更多关注围术期安全防范、术中监测及麻醉调控。     

Dysembryoplastic neuroepithelial tumors: magnetic resonance imaging and magnetic resonance spectroscopy evaluation

Background Dysembryoplastic neuroepithelial tumor （DNT） is a rare benign neoplasm of the central nervous system affecting young people. A correct preoperative diagnosis is helpful for planning surgical strategies and improving prognosis. The purpose of this study was to characterize DNTs using magnetic resonance imaging （MRI） and magnetic resonance spectroscopy （MRS） and to analyze the value of these two techniques in the diagnosis of DNTs. Methods MR images of 13 patients with DNTs were reviewed retrospectively; and five of the patients also underwent MRS. Tumors were confirmed by surgery. The distribution, extension and signal features of the lesions were assessed, and the MRS results were analyzed. Results All tumors were supratentorial. The cortex was the main area involved, with nine tumors located in the temporal lobe, three in the frontal lobe, and one on the boundary between the temporal and occipital lobes. All cases had decreased signal intensity on Tl-weighted MR images and increased signal intensity on T2-weighted images. On fluid attenuated inversion recovery weighted images, the hyperintense ＂ring sign＂ and internal septation of the lesion were seen in 9 cases. Eight tumors had well-demarcated borders. Peritumoral edema or mass effect was absent in all cases. A contrast enhancement examination was performed in 9 cases. Contrast enhancement was absent in five cases, and four cases showed significant enhancement. The MRS showed a low N-acetylaspartate peak and a lack of elevated choline-containing component （Cho） or Cho-Cr ratio （Cho/Cr） in five patients. Conclusions The MRI findings of DNTs were stereotypical. The combination of MRI and MRS techniques were helpful in making a correct presurgical diagnosis.     

Magnetic resonance imaging and magnetic resonance angiography in severe crush syndrome with consideration of fasciotomy or amputation: a novel diagnostic tool

Three cases of severe crush syndrome after the Wenchuan earthquake in China are presented. The patients, 2 males and one female ranging in age from 18-45 years were studied via 1.5 T magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). MRI examinations were performed more than twice on two patients within 60 days of the earthquake. All the patients had acute renal failure (ARF) with plasma myoglobin concentrations above 17 000 μg/L. The T2-weighted and short time inversion recovery (STIR) sequences revealed high intensity lesions in the affected muscles, and enhanced T1-weighted images showed enhancement of partial affected muscles. MRA revealed no signs of arterial occlusion, arteriostenosis, or filling defects of main arteries. All patients were managed medically with continuous venous-venous hemofiltration and other supportive care, and none required fasciotomy or amputation. Repeat MR studies showed that the high intensity lesions seen on the T2-weighted and STIR sequences resolved in parallel with improvement of laboratory studies and clinical course.

     

中枢神经细胞瘤磁共振成像及氢质子磁共振波谱的诊断价值

目的 探讨中枢神经细胞瘤(CNC)的常规磁共振成像(MRI)和氢质子磁共振波谱(1H MRS)的表现特征和诊断价值.方法 回顾性分析5例经手术病理证实的CNC进行常规MRI检查,其中4例加做多体素1H MRS,并分析其MRI及1H MRS表现.结果 5例CNC患者肿瘤特征性位于侧脑室,邻近Monra孔并累及透明隔.在T1加权成像4例呈等低不均匀信号,1例呈等高不均匀信号;T2加权成像呈等高不均匀信号;增强后肿瘤呈中度及明显不均匀强化.4例1H MRS均表现为胆碱峰明显增高,N-乙酰门冬氨酸(NAA)峰下降,胆碱/肌苷比值升高,NAA/肌苷比值降低.结论 20~40岁的患者发生于侧脑室透明隔处邻近Monra孔的肿瘤,结合其MRI及1H MRS表现特征应考虑到CNC诊断.     

3.0T心脏磁共振技术与病毒性心肌炎患儿心肌损伤、左心室结构关联性及对预后的影响

目的 探究3.0T心脏磁共振(cardiac magnetic resonance, CMR)测定T2比值、LGE范围与病毒性心肌炎(viral moycarditis, VMC)患儿心肌损伤、左心室结构关联性及对预后的影响。方法 选取VMC患儿93例作为研究对象,均行3.0T CMR检查,根据6个月预后分为预后良好组(68例)与预后不良组(25例)。比较2组一般资料、血清肌钙蛋白T(cardiac troponin T,cTnT)、磷酸肌酸激酶同工酶(creatine kinase isoenzyme, CK-MB)、左心室结构[舒张期室间隔厚度(inter ventricular septum thickness, IVST)、舒张末容积(end diastolic volume, EDV)、收缩末容积(end systolic volume, ESV)]、CMR检查参数[T2比值、晚期钆增强(late gadolinium enhancement, LGE)范围],分析T2比值、LGE范围与血清cTnT、CK-MB、左心室结构指标相关性及VMC患儿预后的影响因素,并评价T2比值、...     

MRI动态增强在直肠癌诊断中的价值

目的：探讨直肠癌磁共振动态增强检查的影像表现及应用价值.方法：2005年12月-2010年3月96例直肠癌患者于术前行动态增强扫描,其中73例直肠癌患者,绘制时间-信号强度曲线,测量直肠肿瘤、正常直肠肠壁、盆腔淋巴结的峰值时间、峰值、信号强化率、最大信号强化率.比较不同临床病理分期与磁共振动态增强参数值之间的关系.结果：磁共振动态增强检查中,直肠癌相较于正常直肠肠壁具有更早的峰值时间[Tpeak（18.9±6.7） vs （21.4±6.6）,P=0.046 8]及更高的峰值[SIpeak（1 105.9±354.6） vs （805.2±345.8）,P〈0.000 1]、信号强化率[E（191.6±65.4） vs （158.0±67.3）,P=0.028 7].Dukes分期C的直肠癌具有更早的Tpeak值和更高的 Kep（P=0.045 3）.结论：直肠癌的磁共振功能成像可以部分反映肿瘤局部血管情况,为临床治疗与术后评估提供帮助.     

社区人群说谎的功能磁共振研究

目的 探讨社区人群与说谎有关的认知模式及神经联系.方法 对社区志愿者进行说真话及说谎条件下的功能磁共振扫描.使用SPM2软件分析受试在两条件下脑区激活的差异.结果 说谎任务对比说真话任务,受试双侧背外侧前额叶、额内侧回、顶下小叶、右颞下回及小脑激活显著增加.结论 大脑的特定区域参与说谎或说真话,并能被功能磁共振成像(fMRI)检测到.     

Primary cardiac fibroma in an infant: Computed tomography and magnetic resonance imaging findings

Cardiac fibromas (CFs) are benign primary tumors that typically occur during childhood and may be asymptomatic. However, due to the proximity of CFs to the cardiac structure, significant morbidity and mortality may also be anticipated. CFs do not show spontaneous regression and surgical resection generally remains the treatment of choice for these tumors in children. Thus, it is important to take aggressive steps to obtain accurate pretreatment image diagnosis. A full-term male infant was presented to our facility suffering from shortness of breath, after an episode of upper respiratory tract infection at age 1.5 months. Subsequent chest X-ray revealed widening of the mediastinum and trachea deviation. Cardiogenic pathology was suspected. Computed tomography and magnetic resonance imaging were performed, and we confirmed a diagnosis of benign CF. Thoracotomy biopsy of the tumor confirmed the pathological diagnosis.     

利用知识库实现对心脏MR图像的自动分割

目的 研究如何实现对心脏ＭＲ图像的自动化分割问题。方法　通过对图像特征参数的训练,从而有效提取和利 用先验知识。结果　实现对心脏ＭＲ图像的自动化分割。结论　通过提取和利用心脏ＭＲ图像的先验知识,能够很好地 实现心脏分割算法的自动化。     

多参数磁共振成像在前列腺癌中的诊断价值

前列腺癌（PCa）是全球范围内发病率最高的男性恶性肿瘤之一,严重危害着老年男性的身心健康,早期诊断和早期治疗对PCa治疗策略的制定和预后的判断非常关键。目前PCa诊断主要依靠直肠指诊、血清前列腺特异性抗原及经直肠超声引导下穿刺活组织检查。但这些方法的诊断效能均较低。近年来随着功能磁共振成像的推广运用,多参数磁共振成像（mpMRI）成为目前公认的诊断PCa最有效的影像学方法,其不仅能够进行前列腺疾病的鉴别诊断,还能进一步预测PCa病理评分,以及指导后续的靶向穿刺及局部治疗。mpMRI对PCa的精确诊断和后续的个体化治疗意义重大,本文就其在PCa诊断中的研究现状作一综述。     

橄榄脑桥小脑萎缩的磁共振诊断

目的探讨橄榄脑桥小脑萎缩（OPCA）的MRI表现特点，提高对OPCA的认识和早期诊断水平。方法回顾性分析15例OPCA磁共振成像表现。MRI成像采用SE序列，平扫T1wI、T2WI，轴位、冠状位、矢状位成像。结果OPCA的MRI表现有：（1）脑干萎缩变细，以桥脑前后径变小为著，本组15例患者均有此表现；（2）小脑体积变小，小脑沟、裂增宽、加深，半球小叶变细，小脑横径增宽，脑回细，14例为两侧小脑半球对称性缩小，1例为非对称性萎缩，左侧小脑左叶萎缩更明显；（3）15例患者均有四脑室扩大，桥前池、延髓前池增宽。（4）其他表现：3例患者有皮层下多发点状长T1长T2腔隙性脑梗塞；5例患者有大脑皮层萎缩，为轻度萎缩，萎缩程度明显轻于小脑、桥脑。结论OPCA的MRI表现具有特征性，是确诊本病的最佳检查方法。     

Assessment of left ventricular radial deformation by speckle tracking imaging

The left ventricular radial strain in the inner and outer layers was evaluated by using two-dimensional speckle tracking imaging （2DS）. Twenty-five piglets were studied. The short axis views were acquired. Peak systolic radial strain was measured from 6 circumferential points related to 6 standard segments in the inner and outer layers respectively using 2DS methods. The peak positive first derivative （dp/dt） of left ventricular pressure was compared to the radial strain from 2DS. The inner band showed higher peak radial strain values as compared to the outer band at all of the segments （P〈0.0001）, but the differences had significance just in anteroseptal, posterior, inferior and septal segments （P〈0.05）. Good correlation could be found between radial strain of inner and outer layers and peak dp/dt （P〈0.001）. These preliminary results showed that the degree of local deformation or wall thickening of the ventricular wall in its inner layer was more obvious than its outer layer. It is suggested that the 2DS technique is useful and sensitive for better understanding the regional and global myocar- dial motion and its relationship to the complex architecture of myocardium.     

磁共振检查在乳腺肿瘤临床应用的相关进展

随着磁共振检查技术及软、硬件不断发展和成熟，磁共振检查技术对乳腺肿瘤的早期检出、诊断具有重要价值，特别是功能成像及波谱技术的应用，为乳腺肿瘤的诊断及鉴别诊断提供了可靠手段。作者对各种磁共振检查技术在乳腺肿瘤中的临床应用进行综述。     

基于心脏磁共振特征追踪技术的中国正常人左心房功能的定量研究

目的使用心脏磁共振特征追踪（CMR-FT）技术定量评价中国正常人的左心房功能。方法按纳入标准入选磁共振检查结果显示正常的健康人。采用半傅里叶单次激发技术及平衡稳态自由进动序列获得标准心脏各长轴及短轴切面及电影序列,由2名医师独立测量左心房功能参数,包括左心房容积、射血分数、应变及应变率等。男性与女性相对应参数的比较采用两独立样本t检验。不同年龄组间相应参数的比较采用单因素方差分析。结果共纳入63名研究对象,男34名、女29名,≤29岁19名、30～44岁23名、≥45岁21名。左心房各径线：左心房前后径为（26.1±4.5）mm,左右径为（54.8±5.9）mm;左心房储存功能参数：总射血分数为（63.5±6.9）%,总应变为（45.9±11.7）%,总应变率为（1.5±0.5）s^-1;导管功能参数：被动射血分数为（24.6±9.1）%,被动应变为（22.2±8.1）%,被动应变率为（－0.8±0.3）s^-1;泵血功能参数：主动射血分数为（51.3±8.9）%,主动应变为（23.7±9.2）%,主动应变率为（－1.3±0.5）s^-1。除体表面积、左心房各径线及最大容积、主动收缩前容积在男女之间差异有统计学意义（P均<0.05）之外,其余左心房各功能参数性别间差异均无统计学意义（P均>0.05）。不同年龄组间左心房导管功能差异有统计学意义（P<0.05）,而储存及泵血功能差异无统计学意义。相关性分析结果显示左心房总射血分数与总应变、被动射血分数与被动应变、主动射血分数与主动应变均呈正相关（r=0.77、0.74、0.77,P均<0.01）。左心房功能各参数组内相关系数均>0.6,Bland-Altman分析显示2名医师间具有较好的一致性。结论 CMR-FT技术因其高度的可重复性可用于获得中国正常人左心房功能的相关参数。     

fMRI在脑肿瘤诊断中的应用价值初探

目的：探讨fMRI在脑肿瘤诊断、鉴别诊断及肿瘤浸润边界划定中的价值。方法：脑肿瘤35例,均行MR平扫、增强、DWI及MRS。在肿瘤强化区、瘤周区、正常参照区,DWI测量各区域信号值,计算相对表观扩散系数（rADC）值;^1H—MRS行MVS采集NAA、Cho、Cr、Lac等波峰,计算不同区域各代谢物比值均值,比较统计学差异。结果：DWI示肿瘤强化区rADC值在脑膜瘤与星形细胞瘤、转移瘤间有显著性差异（P〈0．05）;瘤周区rADC值在星形细胞瘤与脑膜瘤、转移瘤间有统计学差异（P〈0．05）。多体素^1H—MRS示肿瘤强化区各代谢物比值均值与正常参照区比较有显著性差异（P〈0．05）;瘤周区,星形细胞瘤、转移瘤和脑膜瘤间多组代谢物比值具统计学差异（P〈0．05）。结论：fMRI与常规MRI相结合有助于脑肿瘤的鉴别诊断以及确定病灶浸润范围。