钆喷酸二葡甲胺的致突性研究

本文应用鼠伤寒沙门菌／徽粒体试验，小鼠骨髓细胞微核试验和体外哺乳动物细胞（ＣＨＬ）染色体畸变试验对钆喷酸二葡甲胺进行了致突性研究．结果表明：钆喷酸二葡甲胺各剂量ＴＡ９７，ＴＡ９８，ＴＡ１００，ＴＡ１０２在加和不加Ｓ９条件下均无致突性。在徽核试验中，各剂量诱发小鼠骨髓多染红细胞的微核率与阴性对照相比，无显著差异（Ｐ＞０．０５）染色体畸变试验也未观察到钆喷酸二葡甲胺对体外培养细胞的损伤作用．研究表明，钆喷酸二葡甲胺对原核生物和哺乳动物细胞无致突变作用．     

超小超顺磁性氧化铁颗粒增强磁共振成像与钆喷替酸葡甲胺增强磁共振成像诊断兔颈转移性淋巴结的对比研究

目的 比较超小超顺磁性氧化铁颗粒(USPIO)增强磁共振成像(MRI)与钆喷替酸葡甲胺(Gd-DPTA)增强MRI两种方法诊断兔颈部反应性增生、肿瘤转移性淋巴结的能力.方法 健康成年新西兰大白兔36只,随机平均分为两组,18只制成颈部淋巴结反应性增生模型,18只制成颈部淋巴结肿瘤转移模型.两组模型各取9只行Gd-DTPA增强MRI,9只行USPIO增强MRI.Gd-DTPA增强前行T1WI、T2WI序列扫描,注射Gd-DPTA后80 s行T1WI扫描.USPIO增强前和注射USPIO后24 h,分别行T1WI、T2WI、T2*WI序列扫描.分析增强前后淋巴结信号及形态特点,与大体标本及病理结果进行对照分析.结果 肿瘤组内,Gd-DTPA增强MRI诊断转移性淋巴结的敏感度、特异度、阳性预测值、阴性预测值及准确性分别为62.5%、91.3%、88.2%、70.0%及76.6%,而USPIO增强MRI为95.0%、90.9%、90.5%、95.2%及92.9%,两种方法间敏感度和准确性差异有统计学意义(均P＜0.05).增生组内,Gd-DTPA增强MRI和USPIO增强MRI诊断良性淋巴结的准确性分别为74.2%和87.1%.结论 USPIO增强MRI诊断肿瘤转移性淋巴结的准确性高于Gd-DTPA增强MRI.     

长春瑞滨对人肺腺癌973细胞放射增敏作用的实验研究

目的：探讨长春瑞滨（NVB）对非小细胞肺癌细胞放射效应影响及其与放射的最佳结合序贯。方法：以指数生长期的人肺腺癌973细胞为研究对象，采用克隆形成分析法进行0．1nM及1nMNVB与放射不同结合序贯实验，研究NVB与放射结合效应，利用“多靶单击”数学模型（SF=1-（1-e^-D/D0）N）进行曲线拟合，获得细胞存活曲线及平均致死剂量、准阈剂量、D。比和增敏比等参数，进行效应评估。结果：0．1nM及1nMNVB照前、照后给药组的增敏比（SER）分别为0．957和0．989，1．295和1．042；0．1nM及1nMNVB照前、照后给药组的D0比分别为1．073和1．099，1．374和1．106。表明0．1nMNVB照前、照后给药时均无放射增敏作用；1nMNVB照前、照后给药时均与放射效应具有较明显协同作用，且照前给药组的协同作用明显强于照后给药组。结论：0．1nMNVB不具有增强放射效应的作用，1nMNVB具有较明显放射效应增强作用，且照前给药组的协同作用明显强于照后给药组。     

左金丸对小鼠S180肿瘤细胞获得性多药耐药P—gp的表达及血清肿瘤标志物的影响

目的：研究左金丸、黄连和吴茱萸对小鼠获得性多药耐药S180腹水肿瘤细胞生长的抑制作用,以及对肿瘤细胞P—gP的表达和血清4种肿瘤标志物：（TM）酸性磷酸酶（ACP）、碱性磷酸酶（AKP）、醛缩酶（ALD）和乳酸脱氢酶（LDH）活力的影响。方法：PFC方案建立S180多药耐药细胞模型,将耐药后S180细胞悬液以每只小鼠0．2ml接种于腹腔,黄连、吴茱萸及左金丸灌胃给药7d,观察小鼠体重、脾指数、肝指数、生命延长率（ILS）,流式细胞仪测定P-糖蛋白（P—gp）的表达率,试剂盒检测血清中肿瘤标志物的活力。结果：左金丸给药组对小鼠S180多药耐药细胞增长有明显的抑制作用,能有效降低肝指数,提高脾指数,提高生命延长率（ILS）（60．26％）的作用明高于黄连（21．85％）和吴茱萸单独给药（20．53％）（P〈0．01）。同时,左金丸给药组能有效逆转$180肿瘤细胞中P—gp的表达（2．69％）至接近S180细胞对照组水平（1．65％）,显著低于模型组（16．07％）,也强于黄连（5．69％）及吴茱萸（9．15％）单独给药时的逆转效果。并且左金丸可有效降低血清中ALD（75．944-12．47U·L^-1）和LDH（1632．924-494．48u·L^-1）的活力,提高血清中ACP（103．284-10．36U·100ml^-1）和AKP（34．564-4．91U·100ml^-1）的活力,与黄连、吴茱萸给药组比较有显著性差异（P〈0．01）。结论：黄连和吴茱萸合用能产生明显的配伍协同抗肿瘤作用,对P—gp的表达和血清中肿瘤标志物的影响可能是其抗肿瘤和逆转多药耐药的潜在机制。     

MRI三期增强扫描对脑转移瘤的诊断价值

目的:对比MRI三期增强扫描对脑转移瘤的敏感性及诊断价值，评估最佳增强扫描时间。方法:对40例临床拟诊为脑转移瘤患者，均行磁共振T1WI轴位即时增强扫描、5 min增强扫描及10 min增强扫描，据此分为三组，统计并比较三组图像中脑转移瘤的数量、体积、信号强度比。结果:40例患者中，三组分别显示病灶136个、163个、173个。整个肿瘤体积的中位数在三组分别为79.2 mm3、102.4 mm3、116.8 mm3，延迟5 min和10 min的肿瘤体积明显大于即时增强的肿瘤体积（P<0.000 1）。病灶信号强度比在三组分别为0.16、0.19、0.20，延迟10分钟图像肿瘤增强部分信号强度比明显大于即时增强图像肿瘤的信号强度比（P<0.05），延迟5 min和10 min的图像之间没有显著差异（P=0.65）。结论:注射钆造影剂后的10分钟左右行MRI增强扫描对脑转移瘤的检测具有较高的敏感性。     

NP方案时辰给药治疗23例非小细胞肺癌临床观察

目的：观察在非小细胞肺癌病人中，与常规化疗模式相比，时辰化疗在疗效、毒副反应和生活质量上是否具有优越性。方法：自2004年4月至2006年2月将NT方案以时辰给药方式治疗23例非小细胞肺癌患者为时辰组，给药方法如下：NVB12．5mg／m^2／d，自15：00至03：00，峰值在21：00，d1—d4；PDD20mg／m^2／d，自10：00至22：00，峰值在16：00，d1-d4；同期常规化疗21例作为对照组，对照组常规外周静脉输液，NVB25mg／m^2，d1，d8；PDD25mg／m^2，d3-d5；两组均为21天为1周期，每个病人至少接受2个周期化疗。采用欧洲生命质量协作组癌症核心量表（quality of life questionnaire：cole 30，EORTC QLQ—C30）第三版和肺癌补充问卷QLQ—LC13对患者进行自我问卷调查，所有患者于化疗前1天，2周期化疗结束后1周进行2次评估。两个量表各项原始得分经线性公式转换成0—100，功能量表和整体生活质量量表得分越高提示生活质量越好，而症状量表及单项条目得分越高提示症状越明显，生活质量越差。结果：与对照组相比，时辰组病人的中位TTP提高了1．3个月（6．2月：4．9月，P〈0．05），一年生存率提高了13．25％（60．87％ vs 47．62％，P〈0．05），而中位生存期时辰组为13．8月，对照组为11．9月，时辰组有提高的趋势，但无统计学差异；两组毒副反应：静脉炎（OVS66．67％，P〈0．0001）；恶心呕吐（21．74% vs 90．48％，P〈0．001）；贫血（17．39％ vs 38．1％，P〈0．05）；QLQ—C30量表显示：在对照组中，恶心呕吐和食欲减退两个条目上，化疗后得分显著高于化疗前（P〈0．01），在角色功能、疲乏、便秘和总体生活质量得分上化疗前后的差异也具有统计学意义（P〈0．05）；在时辰组中，化疗后病人情感和认知功能得分显著高于化疗前，总体生活质量得分较化疗前高；QLQ—LC13量表显示：病人的主要症状是呼吸困难、咳嗽和胸痛，经过2个周期的时辰化疗后均得到明显改善。结论：对于非小细胞肺癌病人，与常规给药模式相比，NP方案时辰给药具有更好的疗效、更低的毒副反应和化疗期间更好的生活质量，因此也更易为病人所接受，值得进一步扩大病例数，深入研究。     

紫杉醇联合肿瘤坏死因子相关凋亡诱导配体诱导MCF-7乳腺癌细胞系凋亡机制的研究

目的探讨紫杉醇对肿瘤坏死因子相关凋亡诱导配体（tumor necrosis factor—related apoptosis inducingligand，TRAIL）诱导MCF-7乳腺癌细胞系凋亡的影响及其作用机制。方法MTT法检测不同浓度的单药紫杉醇组、单药TRAIL组和联合给药组1（同时给予紫杉醇和TRAIL）、联合给药组2（先给予TRAIL再给予紫杉醇）、联合给药组3（先给予紫杉醇再给予TRAIL）对MCF-7细胞的抑制作用；流式细胞术AnnexinV—FITC／PI染色法检测不同给药方案对细胞凋亡的影响；RT—PCR法检测紫杉醇对MCF-7细胞TRAIL受体——死亡受体（deathreceptor，DR）4与5表达水平的影响。结果紫杉醇对MCF-7细胞的抑制作用随药物浓度提高而增强，呈剂量依赖性；MCF-7细胞对TRAIL呈一定程度的耐药；联合给药组1（同时给予紫杉醇和TRAIL）与紫杉醇单药组1、TRAIL单药组1比较无协同作用（CDI=1．00，〉0．85）；联合给药组2（先给予TRAIL再给予紫杉醇）与紫杉醇单药组1、TRAIL单药组2比较亦无协同作用（CDI=0．87，〉0．85）；联合给药组3（先给予紫杉醇再给予TRAIL）与紫杉醇单药组2、TRAIL单药组1比较可见协同作用（CDI=0．46，〈0．75）。先给予紫杉醇再给予TRAIL联合给药组（联合给药组3）较单药组凋亡细胞数目多。紫杉醇可诱导MCF-7细胞DR5表达上调，而对DR4表达水平无影响。结论紫杉醇与TRAIL联合可协同抑制MCF-7细胞生长，机制可能与紫杉醇诱导的死亡受体5mRNA表达上调有关。     

颞叶放射性脑病磁共振成像的特征分析

背景与目的：鼻咽癌(nasopharyngeal carcinoma,NPC)放疗后放射性脑病(radiation encephalopathy,REP)的表现形式多样,对其多样性表现的报道并不多,本研究观察NPC放射性脑病的磁共振成像(magnetic resonance imaging,MRI)形态学表现特征并探讨其诊断价值。方法：对104例NPC患者共160处病灶经MRI诊断为颞叶REP的MRI资料进行回顾性分析。在NPC放射治疗8个月～13年进行MRI检查,成像序列包括T1WI,T2WI,111处病灶作了T1WI Gd—DTPA增强,37处病灶有水抑制反转恢复(fluid attented inversion recovery FLAIR)检查,其中2例有磁共振脑血流灌注成像(MR perfusion weighted imaging,MR PWI)。结果：104例REP中累及单侧颞叶48例,双侧颞叶56例,共160个病灶。脑白质病变在T2WI为高信号,信号可均匀一致,但其中59个病灶在高信号区内出现不均匀低信号影;有91个病灶同时伴有灰质病变,表现为T1WI低信号,T2WI高信号;在111个病灶T1WI Gd—DTPA检查中91个病灶出现强化灶;有5个病灶出现出血及含铁血黄素沉着。结论：鼻咽癌放射性脑病表现具有多样性,除了常见的脑白质病变外,脑灰质病变、脑出血及含铁血黄素沉着及血脑屏障破坏等均比较常见;MRI能清楚地显示这些病变。     

急性肿瘤患者右丙亚胺单药与联合华蟾素注射液治疗对阿霉素所致相关性心脏毒性的影响

目的：探讨恶性肿瘤患者右丙亚胺单药与联合华蟾素注射液治疗对阿霉素所致相关性心脏毒性的影响,并对比其疗效。方法选取恶性肿瘤患者166例为研究对象,随机分为单药组（右丙亚胺单药,61例）、联合用药组（联合应用右丙亚胺与华蟾素注射液,75例）与对照组（不予用药处理,30例）。3组患者均采用含蒽环类药物阿霉素的化疗方案。对照组化疗前不予用药处理;单药组化疗前30 min给予注射用右丙亚胺,按与阿霉素剂量比20∶1确定右丙亚胺剂量;联合用药组在化疗前同时给予右丙亚胺与华蟾素注射液15 ml,右丙亚胺用法用量同单药组。结果经4个化疗周期,（1）心脏毒性发生率方面：对照组53．3％,显著高于单药组（29．51％）、联合用药组（8．0％）,P＜0．05;单药组显著高于联合用药组,P＜0．05。（2）心电图方面：3组病例在化疗开始前心电图均无异常改变。化疗过程中右丙亚胺单药组心电图异常者9例（14．75％）、联合用药组7例（9．33％）,均显著低于对照组22例（73．3％）;联合用药组的心电图异常比例显著低于单药组,P＜0．05。（3）CK、CK-MB、TnI方面：单药组与对照组化疗后较本组化疗前显著上升（P＜0．05）;联合用药组化疗后CK、TnI较本组化疗前显著上升（P＜0．05）,CK-MB与化疗前比较差异不显著,P＞0．05。化疗前3组差异不显著（P＞0．05）。化疗后单药组、联合用药组显著低于对照组,P＜0．05;联合用药组显著低于单药组,P＜0．05。（4）超声心动图参数LVIDD、LVISD、A／E、LVEF、FS方面：单药组与对照组化疗前、后均有显著差异（P＜0．05）,但联合用药组化疗后较本组治疗前无显著差异（P＞0．05）。化疗前3患者各超声心动图参数均无显著差异（P＞0．05）,化疗后3组间两两比较均有明显差异（P＜0．05）。结论右丙亚胺与华蟾素注射液对阿霉素所致心脏毒性具有一定的保护作用,联合用药可明显降低心脏毒性的发生率以及毒性程度,维持正常的心电图、心肌酶以及心功能变化,从而增强恶性肿瘤患者对化疗药物毒副作用的耐受能力、提高肿瘤患者的治疗效果。     

富血供肝转移瘤的MRI表现和特点

背景与目的：肝脏是血源性转移癌最好发的器官，正确判断富血供肝转移瘤具有重要的临床价值，本研究探讨富血供肝转移瘤的MRI特征。方法：回顾性分析122例有明确原发肿瘤病史并伴有肝脏转移的病例。根据强化程度，当病灶显示出明显的早期强化（强化程度与胰腺或肾皮质相仿）时，肝转移瘤被认为是富血供的，据此，共有31例符合人选标准，其中男性8例，女性23例，年龄29～77岁，平均年龄51．9岁。所有31例均行上腹部MRI检查（采用1．5T超导MR扫描仪），扫描序列包括T2WIFSE序列，T1WISPGR序列（用于增强前后扫描）。对比剂为钆喷酸葡胺注射液（Gd—DTPA），注射剂量为0．1mmol/kg，注射速率为2ml／s，注射后行Ⅲ期扫描，扫描时间分别为：20、45、90S。所有MR图像由两位有经验的放射科高年主治医师分析并达成一致。结果：31例患者共发现239个肝转移灶，分布于两叶，无特别好发肝段。其中21例转移灶为多发，其余10例为单发转移灶。病灶小于9．5cm。MR图像显示所有病灶于T1WI均为低信号。在T2WI图像上，127个病灶（53％）显示为中等高信号，65个病灶（27％）为中等高信号伴病灶中央更高信号区。增强动脉期显示183个病灶（77％）呈明显的边缘强化，41个病灶（17％）呈弥漫均匀的结节样强化，15个病灶（6％）呈弥漫不均匀强化。增强门脉期，131个病灶表现为与动脉期相仿的强化方式与程度，其中33个病灶表现为较动脉期稍增厚的强化环。结论：根据富血供肝转移瘤的主要特征．大多数病灶可以和肝脏其他富血供病变（如HCC．血管瘤，FNH等）能正确鉴别。     

Magnetic resonance imaging of musculoskeletal lesions: Comparison of three fat-saturation pulse sequences

Fat-saturation (FS) pulse sequences can improve the detection of musculoskeletal lesions. We prospectively compared contrast-enhanced T1-weighted FS spin-echo (SE) images, T2-weighted FS fast spin-echo (FSE) images and inversion recovery (IR) FSE images to determine if any of these three pulse sequences is superior for depicting bone marrow and soft tissue lesions. T1-weighted FS-SE images (400-680/10-20 [TR/TE]) after intravenous injection of gadoliniumdiethylenetriaminepentaacetic acid (DTPA), T2-weighted FS-FSE (2400-4200/96-112) and IR-FSE (3700-6000/12-14/170 [TR/TE/TI]) images were obtained with a 1.5-T magnet system in 35 patients. The visibility, margination and extent of 37 bone marrow and 67 soft tissue lesions, image uniformity, susceptibility and motion artefacts were qualitatively analysed by four radiologists. The number and size of lesions detected, the mean lesion signal-to-noise ratio (S/N) and contrast-to-noise ratio (C/N) were also statistically compared. More bone and soft-tissue lesions were detected on the IR-FSE and T2-weighted FS-FSE than the T1-weighted FS-SE images. The IR-FSE images were significantly better than the T2-weighted FS-FSE and T1-weighted FS-SE images for bone marrow lesion conspicuity (P<0.01). The soft-tissue lesions were also more conspicuous on the IR-FSE and T2-weighted FS-FSE images than on the T1-weighted FS-SE images (P<0.005). The lesion extent and image quality were similar on all three sequences while motion artefacts were most severe on the IR-FSE and least severe on the T1-weighted FS-SE images (P<0.001). Fat saturation was maximal on the IR-FSE images, resulting in a significantly higher mean ON of bone marrow lesions. The mean C/N of soft-tissue lesions was higher on the T2-weighted FS-FSE images although the differences were not significant. The T2-weighted FS-FSE and IR-FSE sequences are superior to the contrast-enhanced T1-weighted FS-SE sequence for depicting musculoskeletal lesions. Bone marrow lesion conspicuity is greater on the IR-FSE images, with comparable scan time and image quality but more motion artifacts.     

Pre- and post-contrast three-dimensional double inversion-recovery MRI in human glioblastoma

Fluid attenuated inversion recovery (FLAIR) MRI sequences have become an indispensible tool for defining the malignant boundary in patients with brain tumors by nulling the signal contribution from cerebrospinal fluid allowing both regions of edema and regions of non-enhancing, infiltrating tumor to become hyperintense on resulting images. In the current study we examined the utility of a three-dimensional double inversion recovery (DIR) sequence that additionally nulls the MR signal associated with white matter, implemented either pre-contrast or post-contrast, in order to determine whether this sequence allows for better differentiation between tumor and normal brain tissue. T1- and T2-weighted, FLAIR, dynamic susceptibility contrast (DSC)-MRI estimates of cerebral blood volume (rCBV), contrast-enhanced T1-weighted images (T1+C), and DIR data (pre- or post-contrast) were acquired in 22 patients with glioblastoma. Contrast-to-noise (CNR) and tumor volumes were compared between DIR and FLAIR sequences. Line profiles across regions of tumor were generated to evaluate similarities between image contrasts. Additionally, voxel-wise associations between DIR and other sequences were examined. Results suggested post-contrast DIR images were hyperintense (bright) in regions spatially similar those having FLAIR hyperintensity and hypointense (dark) in regions with contrast-enhancement or elevated rCBV due to the high sensitivity of 3D turbo spin echo sequences to susceptibility differences between different tissues. DIR tumor volumes were statistically smaller than tumor volumes as defined by FLAIR (Paired t test, P = 0.0084), averaging a difference of approximately 14 mL or 24 %. DIR images had approximately 1.5× higher lesion CNR compared with FLAIR images (Paired t test, P = 0.0048). Line profiles across tumor regions and scatter plots of voxel-wise coherence between different contrasts confirmed a positive correlation between DIR and FLAIR signal intensity and a negative correlation between DIR and both post-contrast T1-weighted image signal intensity and rCBV. Additional discrepancies between FLAIR and DIR abnormal regions were also observed, together suggesting DIR may provide additional information beyond that of FLAIR.     

Solid Focal Liver Lesions: Dynamic and Late Enhancement Patterns with the Dual Phase Contrast Agent Gadobenate Dimeglumine

Introduction

The purpose of this paper is to illustrate contrast enhancement patterns of solid focal liver lesions on dynamic and late phase imaging with gadobenate dimeglumine (Gd-BOPTA).

Imaging Findings

Unenhanced T2- and T1-weighted, dynamic T1-weighted (arterial, portal-venous, and equilibrium) and late phase (1-3 h) Gd-BOPTA-enhanced MR imaging of different focal liver lesions (nodular regenerative hyperplasia, hepatic adenoma, liver adenomatosis, hepatocellular carcinoma, peripheral cholangiocarcinoma, hypervascular metastases, and hypovascular metastases) are shown. Dynamic imaging was performed using GRE T1-w sequences after the bolus injection of 0.1 mmol/kg Gd-BOPTA; late-phase imaging was obtained at 1-3 h after contrast injection.

Conclusions

Dynamic imaging with Gd-BOPTA provides the same information as with conventional gadolinium-based extracellular contrast agents, while late-phase imaging gives additional information for lesion identification and characterization.     

Clinical stage I carcinoma of the uterine cervix value of preoperative magnetic resonance imaging in assessing parametrial invasion

AIMS AND BACKGROUND: The purpose of this prospective study was to assess the efficacy of different MR imaging techniques in the evaluation of parametrial tumor invasion in patients with early stage cervical cancer. METHODS: A total of 73 consecutive patients, clinically considered to have invasive tumor (<3 cm in diameter) confined to the cervix, underwent MR imaging studies at 1 T, according to the following protocol: fast spin-echo (FSE) T2-weighted, gadolinium-enhanced SE T1-weighted, and fat-suppressed gadolinium-enhanced SE T1-weighted sequences. Images obtained with each sequence were evaluated for parametrial invasion with the use of histopathologic findings as the standard of reference. RESULTS: In the assessment of tumor infiltration of the parametrium, with FSE T2-weighted images accuracy was 83%, with SE T1-weighted gadolinium-enhanced images was 65%, and with SE T1-weighted gadolinium-enhanced fat-suppressed images was 72%. The difference between the accuracy rate achieved with FSE T2-weighted images and those obtained with the other two MR sequences was statistically significant (P <0.05). The high negative predictive value (95%) for the exclusion of parametrial tumor invasion was the principal contributor to the staging accuracy obtained with FSE T2-weighted imaging. CONCLUSIONS: Unenhanced FSE T2-weighted imaging is a reliable method for determining the degree of tumor invasion in patients with early stage cervical cancer. Our data suggest that contrast-enhanced sequences, even with the use of the fat suppression technique, have limited value in assessing tumor extension.     

Gadolinium-enhanced MRI of soft tissue masses

The efficacy of gadopentetate dimeglumine (Gd-DTPA) enhanced magnetic resonance (MR) imaging in the diagnosis and differentiation of soft-tissue, neoplastic and non-neoplastic lesion has not been well established. Thirty patients with soft tissue masses (18 neoplastic and 12 non-neoplastic) were studied, using MR imaging with and without administration of Gd-DTPA. Gd-DTPA proved helpful in characterisation of several entities, including differentiation of solid mass from proteinaceous cyst, demonstration of tumour nodules within haemor-rhagic or necrotic masses, and delineation of tumour adjacent to oedema. The use of Gd-DTPA may provide additional information for tissue specificity and, in complicated cases, Gd-DTPA may also provide essential information that cannot be obtained using other methods. We recommend the use of contrast enhanced MR as an adjunct to conventional MR imaging in the initial assessment of musculoskeletal soft tissue masses. However, T2-weighted images show better tissue contrast of the lesions, and are equal to contrast enhanced images in delineation of tumour margins. Non-contrast enhanced images are, therefore, probably adequate for the delineation of lesions for surgical planning when a diagnosis has already been made.     

188例脊柱转移瘤磁共振成像分析

（目的）分析１８８例脊柱转移瘤的ＭＲ表现，探讨其转移途径，生长方式和ＭＲＩ诊断价值，（方法）１８８例脊柱转移瘤患者均有脊柱病变区或原发肿瘤组织学证实，ＭＲ成像采用自旋回波序列，所有病例作了Ｔ１加权成像，质子密度成像和Ｔ２加权成像，４９例作了静脉注射Ｇｄ－ＤＴＰＡ后Ｔ１加权成像，（结果）１８８例共检出椎体转移７５６只，其中５９８只椎体呈现信号／形态异常，１５８例只仅呈现信号异常，９６例伴附件异常，１     

Magnetic resonance imaging of lipoma and atypical lipomatous tumour/well-differentiated liposarcoma: observer performance using T1-weighted and fluid-sensitive MRI

The aim of this study was to evaluate observer performance using T1-weighted spin-echo and fluid-sensitive MRI sequences in distinguishing between lipoma and atypical lipomatous tumour/well-differentiated liposarcoma (ALT/WDL). Magnetic resonance images of 51 patients with benign lipoma and ALT/WDL of the musculoskeletal system were reviewed. There were 33 benign lipomas and 18 ALT/WDL. The character of septa and nodularity of the fatty tumours on T1-weighted spin-echo sequences and the presence of high signal on fluid-sensitive sequences were assessed. Two independent observers took part. Observer agreement was measured. The two observers achieved sensitivities of 100 and 94% for T1-weighted images and 100% each for fluid-sensitive sequences. Specificities were 76 and 64% for T1-weighted and 70 and 73% for fluid-sensitive images. Observer agreement was very good (kappa 0.87 for T1-weighted and 0.88 for fluid-sensitive images). In distinguishing lipoma from ALT/WDL, observer performance was comparable using T1-weighted and fluid-sensitive MR sequences. High sensitivity and moderately high specificity were attained.     

The detectability of brain metastases using contrast-enhanced spin-echo or gradient-echo images: a systematic review and meta-analysis

This study aimed to compare the detectability of brain metastases using contrast-enhanced spin-echo (SE) and gradient-echo (GRE) T1-weighted images. The Ovid-MEDLINE and EMBASE databases were searched for studies on the detectability of brain metastases using contrast-enhanced SE or GRE images. The pooled proportions for the detectability of brain metastases were assessed using random-effects modeling. Heterogeneity among studies was determined using χ² statistics for the pooled estimates and the inconsistency index, I². To overcome heterogeneity, subgroup analyses according to slice thickness and lesion size were performed. A total of eight eligible studies, which included a sample size of 252 patients and 1413 brain metastases, were included. The detectability of brain metastases using SE images (89.2?%) was higher than using GRE images (81.6?%; adjusted 84.0?%), but this difference was not statistically significant (p?=?0.2385). In subgroup analysis of studies with 1-mm-thick slices and small metastases (<5 mm in diameter), 3-dimensional (3D) SE images demonstrated a higher detectability in comparison to 3D GRE images (93.7?% vs 73.1?% in 1-mm-thick slices; 89.5?% vs 59.4?% for small metastases) (p?相似文献   

TECHNICAL ARTICLE: Fusion of high b-value diffusion-weighted and T2-weighted MR images improves identification of lymph nodes in the pelvis

Accurate identification of lymph nodes facilitates nodal assessment by size, morphological or MR lymphographic criteria. We compared the MR detection of lymph nodes in patients with pelvic cancers using T2-weighted imaging, and fusion of diffusion-weighted imaging (DWI) and T2-weighted imaging. Twenty patients with pelvic tumours underwent 5-mm axial T2-weighted and DWI (b-values 0–750 s/mm²) on a 1.5T system. Fusion images of b = 750 s/mm² diffusion-weighted MR and T2-weighted images were created. Two radiologists evaluated in consensus the T2-weighted images and fusion images independently. For each image set, the location and diameter of pelvic nodes were recorded, and nodal visibility was scored using a 4-point scale (0–3). Nodal visualisation was compared using Relative to an Identified Distribution (RIDIT) analysis. The mean RIDIT score describes the probability that a randomly selected node will be better visualised relative to the other image set. One hundred fourteen pelvic nodes (mean 5.9 mm; 2–10 mm) were identified on T2-weighted images and 161 nodes (mean 4.3 mm; 2–10 mm) on fusion images. Using fusion images, 47 additional nodes were detected compared with T2-weighted images alone (eight external iliac, 24 inguinal, 12 obturator, two peri-rectal, one presacral). Nodes detected only on fusion images were 2–9 mm (mean 3.7 mm). Nodal visualisation was better using fusion images compared with T2-weighted images (mean RIDIT score 0.689 vs 0.302). Fusion of diffusion-weighted MR with T2-weighted images improves identification of pelvic lymph nodes compared with T2-weighted images alone. The improved nodal identification may aid treatment planning and further nodal characterisation.