1.5T磁共振STIR序列在外伤性视神经损伤的应用

目的评价1.5T磁共振STIR序列对外伤性视神经损伤诊断的应用价值。方法 2002年3月至2011年12月对69例外伤性视神经损伤患者行1.5T磁共振检查(MRI),磁共振检查序列包括快速自旋回波序列(FSE)T1WI、快速自旋回波序列(FSE)T2WI、脂肪抑制序列短T1反转恢复成像(Short T1 Inversion-Recovery,STIR)等,回顾性分析外伤性视神经损伤的MRI表现。结果 MRI检查在常规(FSE)T1WI序列中显示病灶31例(44.9%),(FSE)T2WI序列中能显示56例(81.2%)外伤性视神经损伤病灶,STIR序列能检出病灶69例(100.0%),病变以STIR序列上表现最明显。结论 MRI能有效显示外伤性视神经损伤的病变部位及范围,其STIR序列可以准确诊断外伤性视神经损伤。     

兔坐骨神经急性挤压伤的MRI成像序列优选

目的:探讨兔坐骨神经急性挤压伤的MRI成像最佳序列及其可行性,为MRI研究动物外周神经损伤提供客观基础.方法:24只新西兰白兔左下肢作为损伤侧,建立坐骨神经急性挤压伤模型,右下肢为假手术侧,于损伤后1周对所有动物坐骨神经进行MRI扫描,扫描序列包括:T1WI、3DT2WI、T2WI/SPIR、STIR、T2WI/SPAIR,观察各序列对损伤侧坐骨神经近、远段显示情况.结果:损伤侧坐骨神经术后1周在T1WI上未见异常变化,3DT2WI、T2WI/SPIR、STIR、T2WI/SPAIR上挤压伤远段神经明显增粗,信号增高,挤压伤近段所有序列未见异常改变.3DT2WI、T2WI/SPIR、STIR、T2WI/SPAIR对损伤神经远段的显示分别为95.65%(23/24)、60%(15/24)、70.83%(17/24)、60%(15/24),提示3DT2WI对损伤神经的显示明显高于其他三序列(P＜0.05),其他三序列对损伤神经的显示无统计学差异(P＞0.05),但STIR序列的图像较SPIR、T2WI/SPAIR清晰.结论:3DT2WI对损伤神经显示率明显高于其他三个序列,常规MRI可以清晰显示兔坐骨神经损伤,3DT2WI及STIR序列是显示外周神经损伤最好的序列.     

低场强磁共振成像常规序列在隐性骨折中的诊断价值

目的探讨低场强磁共振成像(MRI)常规序列显示隐性骨折的敏感性。方法回顾性分析隐性骨折患者120例。分别观察各扫描序列SE T1WI、FSE T2WI及STIR中骨挫伤、隐性骨折线、关节软骨损伤MRI信号表现。结果骨挫伤以STIR序列显示最佳,范围更广泛,STIR序列敏感性为100%。骨折线的显示以T1WI序列最佳,敏感性为95%。关节软骨损伤以T2WI序列显示最佳,敏感性为100%。结论 MRI应为隐性骨折患者首选检查方法,各序列应合理选择,重点观察,避免漏诊。     

磁共振成像脂肪抑制序列对骨挫伤的诊断价值

目的 探讨磁共振成像(MRI)脂肪抑制短时间反转恢复序列(STIR)序列对急性骨挫伤的诊断价值.方法 回顾性分析X线及CT检查为阴性的120例骨挫伤患者的MRI资料进行分析,总结各序列的检出率.结果 STIR序列敏感性高于SE序列,STIR、T1WI、T2WI的检出率分别为100％、72.8％和43.9％,存在着显著的统计学差异(P＜0.05).结论 MRI对骨髓变化具有很高敏感性,尤其是MRI脂肪抑制序列能清晰显示常规X线难以显示的骨髓水肿、出血和骨小梁微骨折.     

低场磁共振对膝关节隐匿性骨折的应用探讨

目的探讨低场磁共振对膝关节隐匿性骨折的应用价值。方法对16例有明确外伤史,临床症状明显,但平片检查阴性的患者行MRI检查。采用国产鑫高益公司XGY OPER 0.35T永磁型MRI扫描仪,常规行矢状位,冠状位扫描,采用常规SE序列T1WI成像、快速SE序列T2WI成像和STIR脂肪抑制序列。结果 16例患者骨髓均出现大片状或斑片状异常信号影,其中13例T1WI序列呈低信号、T2WI序列呈混杂信号,3例T1WI序列呈低信号、T2WI序列呈高信号;全部病灶在STIR脂肪抑制序列均呈明显高或混杂偏高信号。结论 MRI是诊断膝关节隐匿性骨折最理想的方法,STIR作为一种脂肪抑制技术,对骨髓病变的显示有较高的敏感性。     

多发性肌炎/皮肌炎患者MRI影像表现特点分析

目的分析多发性肌炎(PM)/皮肌炎(DM)患者肌肉MRI影像表现特点并探讨其临床使用价值。方法回顾性分析90例PM/DM患者临床资料和肌肉MRI图像,分析其自旋回波序列(T1WI)、快速自旋回波序列(T2WI)、短时翻转恢复序列(STIR)成像特点,并结合血清肌酸激酶(CK)、肌电图(EMG)、穿刺活检检查结果和临床诊断结果探讨MRI检查优劣势和临床应用价值。结果 MRI检查灵敏度92.22%,明显高于CK、EMG和病理活检(78.89%、71.11%和82.22%,P0.05);PM/DM肌肉炎性水肿MRI表现为T1WI低信号或等信号,T2WI和STIR呈高亮信号;PM/DM肌筋膜炎MRI表现为T1WI低信号或等信号,T2WI和STIR呈带状高亮信号;PM/DM皮下组织水肿MRI表现为T1WI低信号或等信号,T2WI和STIR呈异常高信号;PM/DM肌肉萎缩伴脂肪浸润T1WI、T2WI和STIR示正常信号肌群内出现点状或小片状高信号病灶。结论 PM/DM患者应用MRI检查,灵敏度和特异度均较高,其中T1WI信号可清晰显示脂肪浸润病变,T2WI和STIR成像则对炎性水肿、肌肉萎缩及肌筋膜炎有较高鉴别价值,可用于临床早期诊断。     

低场强MRI七种不同序列对脊柱转移瘤诊断的对比研究

目的 探讨低场强MRI七种不同脉冲序列对脊柱转移瘤诊断敏感性的比较,从而选出各序列的优化组合,为低场MR检查脊柱转移瘤扫描提供参考标准.材料与方法经手术病理或活检证实脊柱转移瘤50例,男28例,女22例;年龄为30～80岁,平均年龄55.6岁.采用低场强MRI分别行SE_T1WI、SE～T2WI,增强T1WI、FLASH_T1WI、FLASH_T2WI、TSE_T2WI、STIR扫描.着重对以下4个方面观察①椎体信号异常;②附件受累;③椎管受累;④椎旁软组织胂块.不同扫描序列对椎体病变检出事进行两样本事的X2检验.结果 SE_T1WI检出率高于增强T1WI(P＜0.05),与FLASH_T1WI检出率无统计学差异(P＞0.05).SE_T2WI与TSE_T2WI检出率无统计学差异(P＞0.05),STIR检出率明显高于SE_T2WI(P＜0.05).FLASH_T2WI检出率高于FLASH_T1WI和STIR(P＜0.05).SE_T2WI显示椎管受累最好(100%),其次为TSE_T2WI(92.9%)、FLASH_T2WI、增强T1WI(85.7%),SE_T1WI(42.9%)显示最差.本组发现椎旁软组织肿块36例,FLASH_T2WI(100%)和SE_T2WI(94.4%)可清晰显示软组织肿块与周围神经和椎管的情况.其次为FLASH_T1WI(88.1%)和增强T1WI(83 2%).结论 1、FLASH_T2WI对脊柱转移性肿瘤检出率敏感性高,是低场强MRI诊断脊拄转移瘤必不可少的扫描序列.2、低场强MR诊断脊拄转移瘤最佳扫描组合是SE_T1WI和FLASH_T2WI序列,必要时STIR序列作补充.3、SE_T2WI对显示脊柱转移瘤中脊髓的压迫及受侵是其它序列无法比拟的.TSE_T2WI可以代替SE_T2WI序列,缩短扫描时间.4、T1WI增强扫描有利于显示脊髓受侵情况.     

低场强MRI七种不同序列对脊柱转移瘤诊断的对比研究

目的 探讨低场强MRI七种不同脉冲序列对脊柱转移瘤诊断敏感性的比较,从而选出各序列的优化组合,为低场MR检查脊柱转移瘤扫描提供参考标准.材料与方法经手术病理或活检证实脊柱转移瘤50例,男28例,女22例;年龄为30～80岁,平均年龄55.6岁.采用低场强MRI分别行SE_T1WI、SE～T2WI,增强T1WI、FLASH_T1WI、FLASH_T2WI、TSE_T2WI、STIR扫描.着重对以下4个方面观察①椎体信号异常;②附件受累;③椎管受累;④椎旁软组织胂块.不同扫描序列对椎体病变检出事进行两样本事的X2检验.结果 SE_T1WI检出率高于增强T1WI(P＜0.05),与FLASH_T1WI检出率无统计学差异(P＞0.05).SE_T2WI与TSE_T2WI检出率无统计学差异(P＞0.05),STIR检出率明显高于SE_T2WI(P＜0.05).FLASH_T2WI检出率高于FLASH_T1WI和STIR(P＜0.05).SE_T2WI显示椎管受累最好(100%),其次为TSE_T2WI(92.9%)、FLASH_T2WI、增强T1WI(85.7%),SE_T1WI(42.9%)显示最差.本组发现椎旁软组织肿块36例,FLASH_T2WI(100%)和SE_T2WI(94.4%)可清晰显示软组织肿块与周围神经和椎管的情况.其次为FLASH_T1WI(88.1%)和增强T1WI(83 2%).结论 1、FLASH_T2WI对脊柱转移性肿瘤检出率敏感性高,是低场强MRI诊断脊拄转移瘤必不可少的扫描序列.2、低场强MR诊断脊拄转移瘤最佳扫描组合是SE_T1WI和FLASH_T2WI序列,必要时STIR序列作补充.3、SE_T2WI对显示脊柱转移瘤中脊髓的压迫及受侵是其它序列无法比拟的.TSE_T2WI可以代替SE_T2WI序列,缩短扫描时间.4、T1WI增强扫描有利于显示脊髓受侵情况.     

低场强MRI七种不同序列对脊柱转移瘤诊断的对比研究

目的 探讨低场强MRI七种不同脉冲序列对脊柱转移瘤诊断敏感性的比较,从而选出各序列的优化组合,为低场MR检查脊柱转移瘤扫描提供参考标准.材料与方法经手术病理或活检证实脊柱转移瘤50例,男28例,女22例;年龄为30～80岁,平均年龄55.6岁.采用低场强MRI分别行SE_T1WI、SE_T2WI、增强T1WI、FLASH_T1WI、FLASH_T2WI、TSE_T2WI、STIR扫描.着重对以下4个方面观察①椎体信号异常;②附件受累;③椎管受累;④椎旁软组织肿块.不同扫描序列对椎体病变检出率进行两样本率的χ2检验.结果 SE_T1WI检出率高于增强T1WI(P<0.05),与FLASH_T1WI检出事无统计学差异(P>0.05).SE_T2WI与TSE_T2WI检出率无统计学差异(P>0.05),STIR检出率明显高于SE_T2WI(P<0.05).FLASH_T2WI检出率高于FLASH_T1WI和STIR(P<0.05).SE_T2WI显示椎管受累最好(100%),其次为TBE_T2WI(92.9%)、FLASH_T2WI、增强T1WI(85.7%),SE_T1WI(42.9%)显示最差.本组发现椎旁软组织肿块36例,FLASH_T2WI(100%)和SE_T2WI(94.4%)可清晰显示软组织肿块与周围神经和椎管的情况.其次为FLASH_T1WI(86.1%)和增强T1WI(83.2%).结论 1、FLASH_T2WI对脊柱转移性肿瘤检出率敏感性高,是低场强MRI诊断脊拄转移瘤必不可少的扫描序列.2、低场强MR诊断脊拄转移瘤最佳扫描组合是SE_TIWI和FLASH_T2WI序列,必要时STIR序列作补充.3、SE_T2WI对显示脊柱转移瘤中脊髓的压迫及受侵是其它序列无法比拟的.TSE_T2WI可以代替SE_T2WI序列,缩短扫描时间.4、T1WI增强扫描有利于显示脊髓受侵情况.     

低场强MRI骨髓挫伤的诊断

目的 提高低场强MRI骨髓挫伤的诊断.方法 分析62例X线平片或CT扫描未见异常表现的骨髓挫伤患者低场强MRI征象.结果 62例共有74处骨髓挫伤的病灶,T1WI发现52处病灶(70.2%),T2WI发现36处病灶(48.6%),STIR序列全部病灶显示(100%).结论 低场强MRI选择SE序列与STIR序列组合检查...     

磁共振诊断强直性脊柱炎骶髂关节病变的价值

目的评价磁共振诊断强直性脊柱炎（AS）骶髂关节病变的价值。方法对41例临床拟诊为AS的患者行MRI检查。使用Marconi超导型1.5T磁共振机型,脊柱线圈。患者仰卧位,扫描方位全部为轴位。采用常规SE（spine cho,SE）T1WI（TR 700ms,TE 12ms）序列、快速自旋回波FSE（fast spin echo,FSE）序列T2WI（TR 3000ms,TE90ms）、短时反转恢复（Short T1 Inversion-Recovery,STIR）序列（TR 4000ms,TE 90ms,TI 150ms）。层厚3mm,层间距0.8mm,采集矩阵256x256,NEX=2。结果 ASI级9例,Ⅱ级15例,Ⅲ级11例,IV级6例。侵及髂骨侧34例,侵及骶骨侧7例。I-Ⅱ级MRI主要表现为T2WI滑膜信号增高;T1WI显示软骨不规则增粗或扭曲,T2WI显示软骨信号增高,骨髓水肿信号不均匀增高。Ⅲ-Ⅳ级主要表现为：T2WI软骨信号不均匀增高或减低,骨性关节面有不同程度的破坏。骨质硬化的征象是线样的无信号带不规则增宽。骨髓水肿范围更大。结论 MRI检查方法敏感,无放射性,可以显示X线、CT观察不到的软骨异常、骨髓水肿等早期变化,应作为AS早期诊断的优选检查方法。     

Magnetic resonance imaging of ovarian cystic teratoma

Two patients with ovarian cystic teratoma were imaged using real-time ultrasound and 1.0-T magnetic resonance imaging (MRI) devices. The ultrasound appearance of cystic teratoma varies with the internal contents. If bone or teeth is present, highly echogenic foci with posterior shadow will be identified. The cysts may contain solid areas, septa and fluid-fluid levels. The dermoid cyst filled with fat showing characteristic echogenic appearance might confused with the pelvic fact tissue. MRI is well suited to the evaluation of pelvic disorders. The T1 and T2 relaxation times in different tissues might present with different signal intensities by changing the pulse sequences. Fat, with its relatively short T1 and long T2 times, appears bright on the T1-weighted images (short TE and TR) and T2-weighted images (long TE and TR). However, old hemorrhage has the MRI characteristics of short T1 and long T2 times as fat. The inversion recovery sequence with short inversion time (STIR) will suppress signal from fat tissue and this is of particular value in differentiating dermoid from hemorrhagic cyst. MRI is quite efficient in cases where ultrasound study is equivocal or difficult in the technique.     

膝关节软骨下局灶性骨髓病变的组织学特点

目的 探讨核磁共振(MRI)发现的膝关节软骨下局灶性骨髓病变(bone marrow lesions,BMLs)的组织学表现和特点.方法 收集本院2013年9月至2015年2月因膝关节骨性关节炎行关节置换的40～70岁患者,术前完善患膝MRI,发现非负重区软骨下局灶性BMLs病灶(T1加权低信号区,T2加权及STIR脂肪抑制序列高信号区)者10例,其中男性3例,女性7例;术中获取病灶标本5例,其中男性2例,女性3例,年龄53 ～67(61 ±6)岁.标本切片均行HE染色及番红O/固绿染色,观察BMLs病灶区和相邻对照区组织学表现,Image Pro Plus 6.0图像分析软件测量各类病理组织所占面积比例和骨小梁体积分数(trabecular bone volume,BV/TV).结果 5例局灶性BMLs病灶分别位于髌骨2例,股骨前髁2例,股骨后髁1例;术中见病灶部位表面软骨存在Ⅰ～Ⅳ度损伤,1例髌骨病灶截面为囊性变,其余为松质骨表现;术后病理学观察结果显示:除1例囊变外,其余4例病灶区以正常组织为主,占76.9％,异常组织占23.1％,BV/TV为26.7％,与对照区比较,骨髓坏死(t=-4.0,P=0.029)、异常骨小梁(t=-4.0,P=0.028)、BV/TV(t=6.4,P=0.008)差异有统计学意义.结论 膝关节非负重区软骨下局灶性BMLs病灶表现出一些非特异性异常组织学表现和一定的共性,软骨损伤和骨小梁减少尤为明显.     

计算机体层摄影和核磁共振成像对强直性脊柱炎髋关节改变的对比分析

目的对比分析计算机体层摄影(CT)与核磁共振成像(MRI)技术在强直性脊柱炎(AS)髋关节改变中的应用价值。方法对66例AS髋关节改变患者的髋关节进行CT与MRI技术检查,MRI检查采用冠状面及横断位T1WI、T2WI、快速反转恢复序列(STIR),发现滑膜病变时加做脂肪抑制T1WI增强检查。将检查结果进行影像分析,根据分析结果评价CT与MRI技术检测AS髋关节改变的敏感性。结果 66例AS患者共132个髋关节侧位,CT显示髋臼及股骨头缘虫蚀状囊状骨质破坏14个,韧带骨化6个,关节间隙狭窄7个及关节缘骨质硬化9个;MRI显示髋关节间隙模糊伴狭窄5个,关节面下方骨破坏36个,骨髓水肿39个,骨髓脂肪沉积30个,肌腱韧带附着点炎症34个,关节周围积液55个。MRI增强关节滑膜异常强化32个。CT显示异常的髋关节侧位共15个,MRI显示异常的髋关节侧位共90个,髋关节异常检查率分别为11.4%(15/132)和68.2%(90/132),差异有统计学意义(P<0.01)。结论 CT对于髋关节骨结构改变显示良好,MRI不但能显示早期骨质结构异常,还能显示AS髋关节受累的急性炎症改变,MRI检查有助于AS髋关节受累早期诊断。     

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.

     

使用SPIO对大鼠肝癌模型进行MR增强显像的实验研究

OBJECTIVE: To evaluate the value of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging in the diagnoses of focal liver lesions. METHODS: Twenty rat models of hepatocellular carcinoma were induced by feeding the rats with N-nitrosodiethylamine. Before and after SPIO injection into the rats, MR imaging was performed including the sequences of spin-echo (SE) T1WI (390 ms/14 ms), TSE T2WI (4 100 ms/99 ms), SE Dual-echoes (1 800 ms/20 ms/70 ms), GRE FLASH T2*WI (600 ms/15 ms/15 ), and GRE FLASH T1WI (150 ms/14 ms/70 ). Another 5 normal rats were selected as negative control, which also received SPIO and MR imaging in the same manner as described above. The characteristics of SPIO-enhanced MRI of different liver lesions were analyzed. RESULTS: After SPIO enhancement, the signal intensity of normal liver and cirrhotic liver both decreased, especially on GRE T2*WI. The signal intensity of hepatocellular carcinoma (HCC), regenerative nodules (RN), and focal nodule hyperplasia (FNH) all increased on T1WI images. On T2WI and T2*-weighted images, the signal intensity of HCC remained high, while significant signal loss occurred in RN and FNH. After SPIO administration, the contrast-to-noise (CNR) of HCC on GRE T2*-weighted images was greater than that of other sequences. CONCLUSION: SPIO has not only considerable T2-negative effect but also slightly T1-shortening effect, which is of great value in the differential diagnosis of focal liver lesions.     

骨肉瘤磁共振成像序列选择的评价

目的 研究骨肉瘤患者术前MRI各检查序列对肿瘤髓内侵犯范围判定的精确性及其临床应用价值。方法 收集和比较分析本院自1991年-2001年1月的临床及病理资料完整的骨肉瘤患者28例患者术前MRI各序列影像检查仪器为美国Resonex 0．38T磁共振成像机，扫描序列为：自旋回波(SE序列)，反转恢复序列(STIR)。所有患者均行增强扫描后T1WI扫描。造影剂为Gd-DTPA0．1mmol／kg体重，经肘部浅静脉注射后立即成像。术后病理标本制成切片，进行肿瘤定性分析。结果 MRI成像在骨肉瘤髓内侵犯长径判定上，T2WI、脂肪抑制、增强扫描与T1WI均有显著性差异，在前后径判定上前3种方法与T1WI均无显著性差异，而在左右径判定上，只有脂肪抑制成像与T1WI有显著性差异。结论 SE序列中T1WI(横断位、矢状位、冠状位)应作为对骨肉瘤侵犯范围判定的首选成像方式。     

MRI/MRA 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 ug/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. In conclusion, MRI is the method of choice in patients with a clinical diagnosis of crush syndrome to evaluate the distribution and extension of muscle lesions, and MRA can clearly show the vascular condition of the affected regions, and can help to determine if surgical intervention is necessary.     

MRI快速液体衰减反转恢复脉冲序列技术的颅脑应用探讨

目的：探讨快速液体衰减反转恢复（FLAIR）技术条件及基在颅脑的临床应用价值。方法：对2088例颅脑疾患患者和58例健康体检者进行快速液体衰减恢复序列及常规SE序列磁共振扫描对比分析,并比较快速FLAIR上不同TR、TI、TE组合所得图像质量,结果：FLAIR序列显示病变更敏感,能更好地抑制脑脊液信号,能增加病灶的对比度。TR／TI／TE为8000／2000／200毫秒的组合（TR约为TI的4倍左右）效果更佳。结论：FLAIR技术对颅脑病变的显示优于常规SE序列,能获得更多的病理信息,可作为常规的颅脑MRI检查序列。     

硬膜窦闭塞的MRI表现

目的探讨硬膜窦闭塞的MRI诊断价值。方法15例硬膜窦闭塞病例,用1．5T超导型磁共振机行自旋回波序列横断面、冠状面的T