肝细胞癌经导管动脉化疗栓塞后磁共振扩散加权成像与病理对照研究

目的 探讨肝细胞癌(肝癌)经导管动脉化疗栓塞(TACE)后磁共振扩散加权成像(MRDWI)表现的病理基础.方法 15例经TACE后行Ⅱ期切除的肝癌患者,术前24～48 h进行MRDWI,对标本进行大体病理、HE染色及碱性成纤维细胞生长因子(bFGF)免疫组化染色观察.结果 15例患者中,12例存活瘤区为高信号,3例为等信号.8例凝固性坏死区为低信号,6例为等信号,1例呈高信号.肿瘤存活区表观扩散系数(ADC)值为(1.42±0.16)×10-3mm2/s,坏死区ADC值为(1.58±0.18)×10-3mm2/s,两者差异有统计学意义(P<0.05).TACE术后、Ⅱ期手术切除前的ADC值与肝癌的Edmondson分级、坏死程度有关(均P<0.05).15例患者中,10例肿瘤存活区bFGF蛋白强表达,5例弱表达,肝癌组织bFGF蛋白表达与其ADC值呈负相关(r=-0.552,P=0.033).结论 肝癌TACE后,MRDWI能较好地鉴别存活与坏死肿瘤组织.     

高分辨磁共振成像结合弥散加权成像对直肠癌术前诊断的价值

目的探讨高分辨磁共振成像（MRI）结合横轴位磁共振弥散加权成像（DWI）对直肠癌术前诊断的价值。方法对疑诊直肠癌的55例患者进行前瞻性研究,术前进行高分辨MRI检查,并采用b值分别为600、1000s／mm2对患者进行DWI检查,测量瘤体的表观弥散系数（ADC）值;将影像结果与术后病理作对照。选取15例非直肠病变患者,将正常直肠壁与直肠癌的ADC值进行对照。结果高分辨MRI诊断直肠癌的灵敏度、特异度及符合率分别为95．7％（45／47）、50．0％（4／8）、89．1％（49／55）。高分辨MRI结合DWI诊断直肠癌的灵敏度、特异度及符合率分别为100．0％（47／47）、75．0％（6／8）、96．4％（53／55）。高分辨MRI对直肠癌T分期诊断总准确度为88．9％（40／45）,对T2和T3期诊断准确度分别为87．5％（14／16）和89．6％（26／29）。同一b值下正常直肠壁与直肠癌瘤体的ADC值差异有统计学意义（P〈0．05）;同一b值下不同分化级别直肠癌的ADC值差异无统计学意义（P〉0．05）。结论高分辨MRI结合DWI对直肠癌术前诊断及T分期具有较高的诊断价值,DWI可以作为诊断直肠癌的重要补充序列。     

磁共振弥散加权成像监测乳腺癌新辅助化疗疗效的应用价值

目的 探讨磁共振弥散加权成像(DWI)监测乳腺癌新辅助化疗的早期疗效及评估化疗后残留病灶的价值.方法 前瞻性选取88例术前进行新辅助化疗的乳腺癌患者的89个病灶,用DWI直方图分析化疗过程中肿瘤多层面表观弥散系数(ADC)值的变化,随访新辅助化疗的疗效.比较按DWI图重建所测肿瘤体积与术后病理测量肿瘤体积的相关性.结果 89个乳腺癌病灶中,化疗有效68个,无效21个.化疗有效组和无效组患者在化疗前的肿瘤ADC值分别为(1.049±0.135)× 10-3 mm2/s和(1.171±0.134)×10-3mm2/s,差异有统计学意义(t=-2.731,P=0.009).全组患者化疗前的肿瘤ADC值为(1.087±0.146)×10-3 mm2/s,肿瘤退缩率为70.4%±55.1%,两者呈负相关(r=-0.430,P=0.025).有效组化疗前、化疗1个疗程后和化疗结束时的肿瘤ADC值差异均有统计学意义(均P<0.05).无效组化疗前、化疗1个疗程后和化疗结束时的肿瘤ADC值差异均无统计学意义(均P>0.05).DWI监测化疗结束后残存肿瘤体积与病理结果高度相关(r=0.749,P<0.01).结论 DWI可在乳腺癌新辅助化疗早期通过ADC值变化来监测肿瘤对治疗的反应,评估残存肿瘤大小,从而评价或预测新辅助化疗的疗效.     

磁共振弥散加权成像在胶质瘤分级中的价值

目的 探讨磁共振弥散加权成像(DWI)及表观弥散系数(ADC)在鉴别胶质瘤瘤体区、瘤周区和正常组织中的应用及鉴别胶质瘤良、恶性的价值.方法 采用Philips 1.5T Achieva超导型磁共振成像仪,对46例胶质瘤患者行常规MRI及DWI,弥散系数b值分别取0和1 000 s/mm2,测量瘤体区、瘤周区及对侧正常组...     

脑星形细胞瘤弥散张量成像的初步研究

背景与目的:弥散张量成像(diffusiontensorimaging,DTI)是一种高级的、定量的弥散加权成像形式,它不仅可以计算每一体素内水分子弥散的显著弥散系数(apparentdiffusioncoefficient,ADC),而且可以计算出弥散的各向异性指数。国外对脑肿瘤的研究多采用弥散加权成像,本研究采用DTI方法检测脑内星形细胞瘤患者的肿瘤实质组织、瘤内囊变坏死区、瘤周水肿与正常脑组织中ADC、部分各向异性指数(fractionalanisotropy,FA)及相对各向异性指数(relativeanisotropy,RA)值,及上述指标在星形细胞瘤分级中的价值。方法:对确诊的14例脑星形细胞瘤(1～2级10例,3～4级4例)进行DTI。测定不同组织中ADC、FA及RA值。结果:将14例脑星形细胞瘤作为一组分析时,增强的肿瘤实质组织犤(1.14±0.13)×10-3mm2/s犦、瘤内囊变坏死区犤(2.04±0.50)×10-3mm2/s犦及瘤周水肿组织犤(1.55±0.19)×10-3mm2/s犦的ADC值同正常脑组织犤(0.74±0.08)×10-3mm2/s犦相比均有显著性差异(P<0.05)。肿瘤实性部分的ADC值犤增强区域:(1.14±0.13)×10-3mm2/s,非增强区域:(1.01±0.25)×10-3mm2/s犦同瘤内囊变坏死区、瘤周水肿组织区比较均有显著性差异(P<0.05)。增强的肿瘤实质组织(FA:0.21±0.08,RA:0.23±0.07)、瘤内囊变坏死区(FA:0.14±0.06,RA:0     

Diagnosis value of diffusion-weighted MR imaging with dynamic enhanced scanning toward pancreatic endocrine tumors简

Objective： The aim of our study was to analysis the pictures of conventional magnetic resonance imaging （MR）, diffusion-weighted imaging （DWl） and dynamic enhanced magnetic resonance imaging （DEMRI） of pancreatic endocrine tumors （PETs）, and evaluate diagnostic value of MR, DWl and DEMRI for diagnosing PETs. Methods： DWl and DEMRI scanning toward 13 patients with PETs being confirmed by surgical pathology before surgery on the basis of conventional MR scanning were carried out, and MR findings was analyzed retrospectively. Results： Of 13 patients with PETs there was 11 cases with single lesion, 2 with multiple, and had 15 lesions altogether, of which there were 3 lesions in pancreatic head, 1 in its neck, 2 in its body, 4 in its body and tail, 5 in its tail. MR findings： （1） T1WI signal was low or slightly lower （9/15）, and equal ones （5/15）; （2） T2WI showed high or slightly higher signal （10/15）, and equal ones （5/15）; （3） T1WI with fat suppression： the signal was low （11/15）, mixed signal （2/15）, and equal ones （2/15）; （4） DWI： normal pancreatic tissue exhibited homogeneous intermediate signal, all 15 lesions were high or slightly higher signal, the measured ADC values of tissue of PETs was （1.124 ± 0.252） × 104 mm2/s, and the ADC value of normal pancreatic tissue （1.873 ± 0.157） × 10^3 mm2/s; （5） Enhanced （M3D/LAVA） scanning： among 13 patients with PETs there were 12 pancreatic lesions with significantly enhanced signals in the arterial phase in all 15, and significantly higher than normal pancreatic tissue, and two slight enhancement was slightly higher signal; and 1 no enhancement. Enhanced pattern： homogeneous enhancement were 6 lesions, and the heterogeneous 4, and the edge ring 5. Conclusion： MR and DWl combining with DEMRI help qualitative diagnosis of pancreatic endocrine tumors.     

磁共振弥散加权成像对脊柱转移瘤放疗疗效的评估

[目的]探讨磁共振弥散加权成像（DWI）对脊柱转移瘤放疗疗效的评估价值。[方法]收集30例脊柱转移瘤患者放疗前、后2个月的磁共振图像,所有患者均进行常规MRI及DWI序列。比较常规MRI序列与DWI序列对病灶的检出率。同时对照分析30例患者放疗前、后的DWI信号、ADC值。[结果]放疗前常规MRI扫描共发现病灶48个,累及42个椎体。DWI序列发现病灶56个,累及48个椎体。放疗结束后2个月复查MRI,SET1WI上脊柱转移瘤信号不变或略有下降。FSET2WI上20例信号轻度下降,10例不变。而在临床症状有改善的26例病例中,相对于放疗前,转移瘤DWI信号明显降低。在b=650s／mm2的DWI中,脊柱转移瘤放疗前表观扩散系数（ADC）值为（0．72±0．21）×10-3mm2／s,放疗后ADC值升高到（1．32±0．22）×10-3mm2／s;相邻正常椎体骨髓的ADC值较转移瘤低,且放疗前后没有变化。f结论]DWI序列既可以提高MRI对脊柱转移瘤的检出率,也可以用于监测和评估脊柱转移瘤的放疗疗效。     

Effect of anti-DR5 and chemotherapy on basal-like breast cancer

The purpose is to evaluate sensitivity of basal-like breast cancer to treatment with anti-DR5 alone and in combination with chemotherapy. Cytotoxicity of TRA-8 anti-DR5 alone and in combination with doxorubicin or paclitaxel was examined. The role of a DR5-associated molecule (DDX3) in the regulation of apoptosis by recruitment of cIAP1 to the DR5/DDX3 complex was studied. SUM159 and 2LMP orthotopic xenografts were treated with TRA-8 alone and in combination with Abraxane or doxorubicin, and tumor growth inhibition determined. Diffusion-weighted magnetic resonance imaging was used to monitor early tumor response. The majority (12/15) of basal-like cell lines were very sensitive to TRA-8-induced cytotoxicity (IC(50) values of 1.0-49 ng/ml). In contrast, 8/11 luminal or HER2-positive cell lines were resistant (IC(50) > 1,000 ng/ml). Enhanced killing of basal-like cell lines was produced by combination treatment with TRA-8 and doxorubicin. Majority of basal cell lines expressed lower levels of DR5-associated DDX3 and cIAP1 than luminal and HER2-positive cell lines. TRA-8 inhibited growth of basal xenografts and produced 20% complete 2LMP tumor regressions. TRA-8 and chemotherapy produced greater 2LMP growth inhibition than either alone. An increase in apparent diffusion coefficient in 2LMP tumors was measured in a week of therapy with TRA-8 and Abraxane. Basal-like cell lines were more sensitive to TRA-8-mediated cytotoxicity than HER2-over-expressing and luminal cell lines, and chemotherapy enhanced cytotoxicity. High sensitivity of basal cells to TRA-8 correlated with low expression of DR5/DDX3/cIAP1 complex. Treatment with TRA-8 and chemotherapy may be an effective therapy for basal-like breast cancer.     

Diffusion-weighted MR imaging in the evaluation of renal tumours

The aim of this study was to evaluate the capability and the reliability of diffusion-weighted MR imaging to differentiate benign from malignant renal lesions. Twenty healthy volunteers and 48 patients with known renal lesions underwent MR of the kidneys by using a 1.5 T superconductive magnet. Diffusion-weighted images (DWI) were obtained on the axial plane during breathhold (17 s) with a SE EPI single shot sequence using a b value of 500 s/mm2. One region of interest (ROI) (lesions < than 3 cm) or 3 ROI (lesions > than 3 cm) were placed within the lesion for the measurement of apparent diffusion coefficient (ADC). ADC map was obtained at each slice position. Mean ADC value in normal renal parenchyma was 2.2 +/- 0.20 x 10(-3) mm2/s, while ADC values in simple cysts (n = 20) were higher (mean ADC values 3.65 +/- 0.09 x 10(-3) mm2/s). Solid benign and malignant renal tumors (n = 19) showed a mean ADC value of 1.7 +/- 0.48 x 10(-3) mm2/sec. The comparison between ADC values in normal parenchyma group and tumour group were found to be statistically significant (p < 0.0001). ADC values of cystic renal cell carcinomas were higher than those of clear cell carcinomas (p < 0.001). In conclusion, DW MRI of the kidney seems to be a reliable means for differentiating normal renal parenchyma from different renal tumors.     

CT结合DWMRI评价非小细胞肺癌放化疗疗效研究

目的 当前,肺癌非手术治疗后疗效评价主要通过观察肿瘤体积大小的变化来进行判断,但对于肿瘤细胞功能状态的改变方面存在一定局限性.本研究旨在探讨CT结合磁共振弥散加权成像(diffusion-weighted magnetic resonance imaging,DWI)综合评价非小细胞肺癌放化疗疗效新标准的应用研究.方法 选取2010-09-01-2014-09-30河北医科大学收治接受三维放疗的非小细胞肺癌患者48例,处方剂量58~66 Gy,单次2~2.2 Gy,同期1~2个周期化疗.放疗前、放疗末行CT扫描及DWI检查,应用CT标准、DWI高信号表达情况及表观弥散系数(apparent diffusion coefficient,ADC)评价放化疗疗效,并与生存相结合进行预后分析.结果 (1)CT评价的CR、PR和NR三组无进展生存率差异有统计学意义(χ2=10.906,P=0.001),三组原发灶放疗前ADC值依次逐渐升高,ADC值变化幅度逐渐减小,放疗末ADC值PR组明显高于NR组.(2)放疗末原发灶及淋巴结DWI高信号完全消失组生存情况明显优于部分消失组(χ2=7.521,P=0.006),高信号完全消失组放疗前原发灶ADC值较低,放疗末原发灶及残余淋巴结ADC值升高更显著.(3)CT疗效评价为PR的34例的患者中,放疗末有7例原发灶及淋巴结DWI高信号完全消失,无局部复发者;另27例原发灶及淋巴结DWI高信号未完全消失者,共有20例出现局部复发(0 vs 77.0%).(4)CT结合DWI综合疗效评价,完全缓解组与部分缓解组1、2、3、4年无进展生存率分别为66.7%、33.3%、25.0%、25.0%和44.0%、4.0%、4.0%、4.0%,无缓解组生存期最长者10个月,χ2=13.896,P<0.001.Cox回归模型多因素分析结果显示非手术N分期、CT结合DWI疗效评价为独立预后影响因素.结论 DWI能对肺癌放化疗疗效进行判断并预测预后.DWI检查可弥补CT在评价瘤细胞功能状态改变方面疗效的不足,二者相结合共同评价疗效可能更客观,更能提示预后.     

Antiangiogenic treatment with three thrombospondin-1 type 1 repeats versus gemcitabine in an orthotopic human pancreatic cancer model.

PURPOSE: In this study, we investigated the antitumor efficacy of thrombospondin-1 three type 1 repeats (3TSR), the antiangiogenic domain of thrombospondin-1, in comparison and in combination with gemcitabine, in an orthotopic pancreatic cancer model. EXPERIMENTAL DESIGN: Human pancreatic cancer cells were injected into the pancreas of severe combined immunodeficient mice. The animals were treated with 3TSR, gemcitabine, 3TSR plus gemcitabine, or vehicle for 3 weeks. Subsequently, the effects of 3TSR and/or gemcitabine on tumor growth, tumor necrosis, microvessel density, cancer cell proliferation, apoptosis, and endothelial cell apoptosis were analyzed. RESULTS: After 3 weeks of treatment, 3TSR reduced tumor volume by 65%, and gemcitabine by 84%. Tumor volume was not statistically different between gemcitabine group and combinatorial treatment group. Extensive necrotic areas were observed in tumors from 3TSR-treated mice, whereas tumors from gemcitabine and combinatorially treated mice were less necrotic than control tumors. 3TSR reduced tumor microvessel density and increased tumor blood vessel endothelial cell apoptosis. In contrast, gemcitabine induced apoptosis and inhibited proliferation of cancer cells. CONCLUSION: 3TSR, the antiangiogenic domain of thrombospondin-1, showed comparable antitumor efficacy to gemcitabine in a human pancreatic cancer orthotopic mouse model. No synergistic effect was found when the two drugs were combined and possible reasons are discussed in detail. A delicate balance between normalization and excessive regression of tumor vasculature is important when initiating alternative combinatorial regimens for treatment of patients with pancreatic cancer.     

IP-10质粒联合吉西他滨抗肿瘤作用的实验研究

背景与目的:IP鄄10是α趋化因子家族成员,IP鄄10具有抗肿瘤血管作用,表现为抑制新生血管分化成毛细血管。研究表明,化疗与抗肿瘤血管治疗结合具有协同作用。本研究拟用IP鄄10质粒与化疗药物吉西他滨联合治疗肿瘤,观察其抗肿瘤作用。方法:质粒pBLAST鄄IP鄄10转化至大肠杆菌中,经扩增后,制备并纯化质粒。采用BALB/c及C57BL/6小鼠,分别建立H22肝癌及Lewis肺癌肿瘤模型。IP鄄10质粒及生理盐水肌肉注射,吉西他滨腹腔注射。收集小鼠血清,ELISA方法检测血清中IP鄄10蛋白表达;观察肿瘤体积变化、小鼠存活期及不良反应;肿瘤组织微血管免疫组化染色,确定微血管密度;TUNEL法检测肿瘤组织中细胞凋亡。结果:IP鄄10质粒肌注后小鼠血清中IP鄄10蛋白表达于第2周达高峰[(16.8±3.6)ng/ml],至第5周仍持续有较高水平表达[(14.0±2.1)ng/ml]。IP鄄10质粒联合吉西他滨组小鼠肿瘤体积较对照组显著受抑甚至消退,在接种肿瘤细胞后第9周联合给药组小鼠存活率为90%,明显高于其他各组(IP鄄10质粒组55%,吉西他滨组以及生理盐水组为0%)(P<0.005);各组小鼠均未出现明显的不良反应。肿瘤组织内微血管密度在联合给药组为15.8±2.4,显著低于其它各组(IP鄄10组45.6±2.0,吉西他滨组50.2±3.5和生理盐水组51.3±3.0)(P<0.01)。在接种肿瘤细     

Anti-tumor efficacy of the nucleoside analog 1-(2-deoxy-2-fluoro-4-thio-beta-D-arabinofuranosyl) cytosine (4'-thio-FAC) in human pancreatic and ovarian tumor xenograft models

1-(2-deoxy-2-fluoro-4-thio-beta-D-arabinofuranosyl) cytosine (4'-thio-FAC) is a deoxycytidine analog that has been shown previously to have impressive anti-proliferative and cytotoxic effects in vitro and in vivo toward colorectal and gastric tumors. In our present studies, the pharmacokinetic behavior in nude mice and the effectiveness of 4'-thio-FAC against human pancreatic and ovarian tumor growth were assessed in comparison with standard chemotherapeutic agents. Potent in vitro anti-proliferative effects were observed against pancreatic (Capan-1, MIA-PaCa-2, BxPC-3) and ovarian (SK-OV-3, OVCAR-3, ES-2) cancer cell lines with IC(50) of 0.01-0.2 microM. In vivo anti-tumor activity was evaluated in nude mice bearing subcutaneously (s.c.) implanted human pancreatic tumor xenografts or intraperitoneally (i.p.) disseminated human ovarian xenografted tumors. Oral daily administration of 4'-thio-FAC for 8-10 days significantly inhibited the growth of gemcitabine-resistant BxPC-3 pancreatic tumors and induced regression of gemcitabine-refractory Capan-1 tumors. 4'-Thio-FAC was also a highly effective inhibitor of ovarian peritoneal carcinomatosis. In the SK-OV-3 and ES-2 ovarian cancer models, 4'-thio-FAC prolonged survival to a greater extent than that observed with gemcitabine. Furthermore, the superiority of 4'-thio-FAC to carboplatin and paclitaxel was demonstrated in the ES-2 clear cell ovarian carcinoma model. Studies provide evidence that 4'-thio-FAC is a promising new alternative to gemcitabine and other chemotherapeutic drugs in the treatment of a variety of tumor indications, including pancreatic and ovarian carcinoma.     

后颅窝脑肿瘤的多模态磁共振成像诊断研究

目的:探讨多模态磁共振成像在后颅窝脑肿瘤中的诊断价值。方法:回顾性分析经病理证实的18例后颅窝脑肿瘤患者的MR平扫、扩散加权成像（DWI）、动态增强影像资料。结果:18例患者共有22个病灶,3例为多发病灶。所有病灶在T1WI呈低或稍低信号;T2WI上16个病灶呈稍高信号,3个呈等信号,3个呈混杂稍高信号;DWI上3例扩散受限呈高信号,12例扩散稍受限呈稍高信号,3例扩散不受限呈等信号。表观扩散系数（ADC）图上测得肿瘤实质与对照侧平均ADC值分别为(0.595±0.089)×10-3 mm2/s和(0.695±0.051)×10-3 mm2/s,两者差异有统计学意义(P=0.03),rADC为0.875±0.119。结论:多模态磁共振成像有助于后颅窝脑肿瘤的明确诊断。     

Gemcitabine versus cisplatin, epirubicin, fluorouracil, and gemcitabine in advanced pancreatic cancer: a randomised controlled multicentre phase III trial

BACKGROUND: Patients with advanced pancreatic adenocarcinoma have a poor response, progression-free survival, and overall survival with standard treatment. We aimed to assess whether a four-drug regimen could improve 4 month progression-free survival compared with gemcitabine alone. METHODS: In a randomised multicentre phase III trial, 52 patients were randomly assigned to 40 mg/m2 cisplatin and 40 mg/m2 epirubicin both given on day 1, 600 mg/m2 gemcitabine given intravenously over 1 h on days 1 and 8, and 200 mg/m2 fluorouracil a day given by continuous infusion on days 1-28 of a 4-week cycle (PEFG regimen), and 47 were assigned to 1000 mg/m2 gemcitabine given intravenously over 30 min once a week for 7 of 8 consecutive weeks in cycle 1 and for 3 of 4 weeks thereafter. The primary endpoint was 4-month progression-free survival. Secondary endpoints were overall survival, objective response, safety, and quality of life. Analyses were by intention to treat. FINDINGS: 51 patients assigned PEFG and 46 assigned gemcitabine alone had disease progression. 49 patients in the PEFG group and 46 in the gemcitabine group died from progressive disease. More patients allocated PEFG than gemcitabine alone were alive without progressive disease at 4 months (60% [95% CI 46-72] vs 28% [17-42]; hazard ratio [HR] 0.46 [0.26-0.79]). 1-year overall survival in the PEFG group was 38.5% (25.3-51.7) and in the gemcitabine group was 21.3% (9.6-33.0; HR 0.68 [0.42-1.09]). More patients assigned PEFG showed disease response than did those assigned gemcitabine (38.5% [25.3-51.7] vs 8.5% [0.5-16.5]; odds ratio 6.60 [2.11-20.60], p=0.0008). More patients in the PEFG group had grade 3-4 neutropenia and thrombocytopenia than in the gemcitabine group (p<0.0001). INTERPRETATION: The PEFG regimen could be considered for treatment of advanced pancreatic adenocarcinoma.     

Diffusion Weighted Imaging Can Distinguish Benign from Malignant Mediastinal Tumors and Mass Lesions: Comparison with Positron Emission Tomography

Background: Diffusion-weighted magnetic resonance imaging (DWI) makes it possible to detect malignanttumors based on the diffusion of water molecules. It is uncertain whether DWI is more useful than positronemission tomography-computed tomography (PET-CT) for distinguishing benign from malignant mediastinaltumors and mass lesions. Materials and Methods: Sixteen malignant mediastinal tumors (thymomas 7, thymiccancers 3, malignant lymphomas 3, malignant germ cell tumors 2, and thymic carcinoid 1) and 12 benignmediastinal tumors or mass lesions were assessed in this study. DWI and PET-CT were performed before biopsyor surgery. Results: The apparent diffusion coefficient (ADC) value (1.51±0.46 ×10-3mm2/sec) of malignantmediastinal tumors was significantly lower than that (2.96±0.86 ×10-3mm2/sec) of benign mediastinal tumors andmass lesions (P<0.0001). Maximum standardized uptake value (SUVmax) (11.30±11.22) of malignant mediastinaltumors was significantly higher than that (2.53±3.92) of benign mediastinal tumors and mass lesions (P=0.0159).Using the optimal cutoff value (OCV) 2.21×10-3mm2/sec for ADC and 2.93 for SUVmax, the sensitivity (100%) byDWI was not significantly higher than that (93.8%) by PET-CT for malignant mediastinal tumors. The specificity(83.3%) by DWI was not significantly higher than that (66.7%) for benign mediastinal tumors and mass lesions.The accuracy (92.9%) by DWI was not significantly higher than that (82.1%) by PET-CT for mediastinal tumorsand mass lesions. Conclusions: There was no significant difference between diagnostic capability of DWI andthat of PET-CT for distinguishing mediastinal tumors and mass lesions. DWI is useful in distinguishing benignfrom malignant mediastinal tumors and mass lesions.     

磁共振扩散加权成像在乳腺病变鉴别诊断中的应用价值

背景与目的:磁共振扩散加权成像(diffusion weighted imaging,DWI)是目前惟一能观察活体水分子微观运动的成像方法,能够检测出与组织含水量改变有关的形态学和病理学的早期改变,已广泛应用于脑部病变的诊断和鉴别诊断,但在乳腺病变诊断中的应用目前仍处于研究探索阶段.本文目的在于探讨DWI在乳腺病变鉴别诊断中的价值.方法:分析52例经手术病理学检查证实的乳腺疾病患者的DWI资料,包括恶性病灶27个,良性病变36个.DWI采用单次激发平面回波成像(echo planar imaging,EPI)技术.以10例正常乳腺为对照组.测量病灶的表观扩散系数(apparent diffusion coefficient,ADC)值,比较良恶性病变、正常腺体ADC值是否具有显著性差异.采用接收者工作特征曲线(receiver operating characteristic curve,ROC)确定ADC值的诊断阈值,并用于诊断.结果:DWI对乳腺病变的显示良好.良性病变平均ADC值为(1.59±0.26)×10-3 mm2/s,95%参考值范围为(1.07～2.11)×10-3 mm2/s;恶性病灶平均ADC值为(0.87±0.23)×10-3 mm2/s,95%参考值范围(0.42～1.32)×10-3 mm2/s;正常腺体ADC值为(1.98±0.31)×10-3mm2/s.95%参考值范围(1.38～2.58)×10-3 mm2/s,三组ADC值之间均有显著性差异(P＜0.05).ROC曲线下面积(Az值)为0.96(95%可信区间0.92～1.00),诊断阈值为1.22×10-3 mm2/s.以此值作为良、恶性判断标准,敏感性88.9%,特异性87.9%,准确性85.0%.结论:ADC值有助于乳腺病变的鉴别诊断,DWI在乳腺癌的诊断上具有临床应用前景.     

磁共振扩散加权成像在鉴别鼻咽癌放疗后鼻咽坏死与复发中的价值

目的评价磁共振扩散加权成像（DWI）以及表观扩散系数（ADC）值测量在鼻咽癌放疗后鼻咽坏死与复发鉴别诊断中的应用价值。方法2008年7月至2010年12月,35例经我院治疗并经病理诊断证实的鼻咽癌放疗后鼻咽坏死和同期随机选取的35例鼻咽癌放疗后复发的患者,均接受了常规MRI检查及DWI（扩散敏感系数,即b值采用：0s／mm2及800s／mm2）,分别测量放疗后鼻咽坏死灶及肿瘤复发区的ADC值,计算其平均值。结果鼻咽坏死灶在DWI上表现为不均匀的低信号,而肿瘤复发病灶表现为高信号。鼻咽坏死组及复发组ADC平均值分别为（1.073±0．0383）×10^-3mm2／s和（0．844±0．0309）×10^-3mm2／s;最大值分别为（1．728±0．0527）×10^-3mm2／s和（1．477±0．0675）×10^-3mm2／s。鼻咽坏死组ADC平均值及最大值均大于复发组,差异有统计学意义（t1=4．645,P〈0．001;t2=2．932,P〈0．005）。结论DWI以及ADC值测量在鼻咽癌放疗后鼻咽坏死与复发的鉴别诊断中具有重要价值,可作为常规MR序列的重要补充。     

Differentiation of Benign from Malignant Adnexal Masses by Functional 3 Tesla MRI Techniques: Diffusion-Weighted Imaging and Time-Intensity Curves of Dynamic Contrast-Enhanced MRI

Background: The aim of this study was to evaluate and compare the accuracy of diffusion-weighted imaging(DWI), apparent diffusion coefficient (ADC) value, and time-intensity curve (TIC) type analysis derived fromdynamic contrast-enhanced MR imaging (DCE-MRI) in differentiating benign from malignant adnexal masses.Materials and Methods: 47 patients with 56 adnexal masses (27 malignant and 29 benign) underwent DWI andDCE-MRI examinations, prior to surgery. DWI signal intensity, mean ADC value, and TIC type were determinedfor all the masses. Results: High signal intensity on DWI and type 3 TIC were helpful in differentiating benignfrom malignant adnexal masses (p<0.001). The mean ADC value was significantly lower in malignant adnexalmasses (p<0.001). An ADC value<1.20×10-3 mm2/s may be the optimal cutoff for differentiating between benignand malignant tumors. The negative predictive value for low signal intensity on DWI, and type 1 TIC were 100%.The pairwise comparison among the receiver operating characteristic (ROC) curves showed that the area underthe curve (AUC) of TIC was significantly larger than the AUCs of DWI and ADC (p<0.001 for comparison ofTIC and DWI, p<0.02 for comparison of TIC and ADC value). Conclusions: DWI, ADC value and TIC typederived from DCE-MRI are all sensitive and relatively specific methods for differentiating benign from malignantadnexal masses. By comparing these functional MR techniques, TIC was found to be more accurate than DWIand ADC.     

磁共振扩散加权成像在鼻咽癌放疗随访中的应用价值

目的 探讨磁共振扩散加权成像（DWI）在鼻咽癌（NPC）放疗后随访复查中的临床应用价值。方法 收集83例NPC放疗后复查的患者,将放疗后6个月内分为残留组（4例）和无残留组（33例）,6个月以上分为复发组（5例）和无复发组（41例）,行鼻咽部常规磁共振和DWI检查,对鼻咽局部残存肿块或鼻咽壁增厚、骨质破坏缺损处及两侧翼外肌进行表观扩散系数（ADC）测量。结果全组NPC患者翼外肌的ADC值（mm2/s）为（1.501±0.069）×10-3,无残留组、残留组、无复发组和复发组的ADC值（mm2/s）分别为（1.843±0.133）×10-3、（1.097±0.183）×10-3、（1.884±0.134）×10-3和（0.787±0.067）×10-3,残留组和复发组的ADC值明显低于翼外肌,无残留组和无复发组的ADC值明显高于翼外肌,差异均有统计学意义（P＜0.05）。结论DWI能够提供细胞水平的定性和定量信息,通过对感兴趣区ADC值的测量,可以敏感而准确地鉴别NPC放疗后残留、纤维化斑块和肿瘤复发。