扩散加权成像及临床病理特性对宫颈癌同步放化疗复发的诊断价值

目的 回顾性分析扩散加权成像(DWI)技术及临床病理特性预测宫颈癌同步放化疗复发的价值.方法 选取于放化疗前及放化疗后4周行DWI扫描的宫颈癌患者72例,其中放化疗后复发患者14例.比较放化疗前后及复发组与未复发组肿瘤表观扩散系数(ADC)值、ADC改变量及肿瘤临床病理的差异,回归分析宫颈癌复发的危险因素.结果 同步放...     

磁共振扩散加权成像预测与评价宫颈癌放化疗疗效的研究

目的 探讨磁共振扩散加权成像(DWI)在预测与评价宫颈癌放化疗疗效中的应用价值.方法 收集282例经病理检查证实为宫颈癌的患者,分别在治疗前、治疗结束后行DWI检查,测量肿瘤最大径和表现扩散系数(ADC)值.治疗结束后,依据实体肿瘤疗效评价标准(RECIST)将患者分为缓解组、无效组.根据治疗结束后2年的随访复查情况将患者分为复发组、无复发组.比较两组间的治疗前和治疗结束后ADC值,并分析疗效及复发情况与治疗前ADC值、治疗结束后的ADC升高值之间的相关性. 结果 缓解组223例,无效组59例.复发组70例,无复发组212例.缓解组治疗前ADC值明显低于无效组(t=3.274,P<0.05),无复发组治疗前ADC值明显低于复发组(t=1.031,P<0.05).治疗前ADC值低的患者复发率明显低于治疗前ADC值高的患者(χ²=5.175,P<0.05).治疗结束后的疗效及治疗结束后2年的复发情况与治疗前ADC值均呈负相关(r=-0.571、-0.675,P<0.05),与治疗结束后的ADC升高值均呈正相关(r=0.641、0.547,P<0.05).缓解组、无复发组治疗结束后ADC值升高明显(t=2.031、4.011,P<0.05),无效组、复发组ADC值升高不明显.结论 治疗前的ADC值有助于预测宫颈癌放化疗疗效,治疗结束后的ADC变化值有助于评价宫颈癌放化疗疗效.     

磁共振扩散加权成像预测、监测直肠癌放化疗效果的价值

目的探讨MR扩散加权成像(diffusion-weighted imaging,DWI)在预测、监测直肠癌放、化疗效果中的应用价值。资料与方法动态监测15例行放、化疗的直肠癌患者,于放化疗前、放化疗结束和放化疗后4~5周行3次常规MRI及DWI。测量直肠癌的长度、肿瘤侵犯直肠壁厚度和表观扩散系数(apparent diffusion coefficient,ADC)值在放化疗前、后各时间点的变化,并分别进行比较;依据实体瘤疗效评价标准(RECIST)分组,比较各组在放化疗前ADC值之间的差异。结果直肠癌放化疗结束时,肿瘤侵犯肠壁的厚度较放化疗前差异有统计学意义(0.010.05);而对于放化疗结束与放化疗后4~5周,三者的变化差异均无统计学意义。放化疗前部分缓解(PR)与病灶稳定(SD)组之间的ADC值差异无统计学意义(P=0.222>0.05)。结论 DWI可优先、准确评价直肠癌放化疗的疗效相对于肿瘤形态学变化;而放化疗前ADC值对于预测直肠癌放化疗的疗效无明显意义...     

MR扩散成像对宫颈癌放化疗早期疗效的评价

目的：探讨MR扩散成像评价晚期宫颈癌放化疗早期疗效的价值。方法：对18例经病理证实为晚期宫颈癌并接受放化疗的患者,在治疗前和开始治疗后2周、及治疗结束后行常规MRI及DWI检查。测量治疗前和治疗后不同时间点肿瘤最大径和ADC值,按治疗后肿瘤直径的变化进行分组,分析各组治疗前和治疗后不同时间点ADC值差异。结果：治疗后2周ADC值升高,完全缓解（CR）组ADC值变化高于部分缓解（PR）组,差异具有统计学意义（P〈0.05）。结论：MR扩散成像可以作为晚期宫颈癌放化疗早期评价的指标,并可根据ADC值升高情况预测治疗效果。     

3.0T MR扩散加权成像对宫颈癌放化疗疗效的评估价值

目的：探讨扩散加权成像（DWI）对宫颈癌放化疗疗效的评估价值。方法：46名接受全程放化疗治疗的宫颈癌患者分别在治疗前、治疗2周后、外照射25次后及治疗结束后进行盆腔常规MRI及DWI扫描,每次扫描均测量肿瘤的直径及ADC值。根据治疗结束6个月后的随访结果将患者划分为完全有效组（CR）、部分有效组（PR）及无效组（SD）。计算并两两比较各次 MRI扫描测得的肿瘤ADC值及直径的动态变化值。结果：CR 组在治疗2周及外照射25次的 ADC值提高均高于 RP 组及 SD 组（P＜0．05）,治疗结束后 CR 组的 ADC 值与 PR 组及 SD 组间差异均有统计学意义（P＜0．05）。治疗前、放化疗2周后及外照射25次后各肿瘤组（CR、PR、SD组）的ADC 值、肿瘤最大直径之间差异均无统计学意义（P＞0．05）。结论：DWI可作为预测及监测宫颈癌放化疗疗效的有效方法。     

磁共振扩散加权成像在肝纤维化诊断中的应用

肝炎-肝纤维化-肝硬化-肝细胞癌是逐渐发展的病理过程,其中肝纤维化是唯一可逆性阶段。有关肝纤维化早期诊断和治疗的研究是当今临床及医学影像学研究的热点和难点。磁共振扩散加权成像(DWI)是近年开发并趋向成熟的功能成像技术,尤其对肝纤维化有望成为其早期诊断无创而有效的手段。现就DWI的成像方法及其对肝纤维化病理分级、分期等应用现状予以综述。     

磁共振扩散加权成像在肝纤维化诊断中的应用

肝炎-肝纤维化-肝硬化-肝细胞癌是逐渐发展的病理过程,其中肝纤维化是唯一可逆性阶段。有关肝纤维化早期诊断和治疗的研究是当今临床及医学影像学研究的热点和难点。磁共振扩散加权成像（DWI）是近年开发并趋向成熟的功能成像技术,尤其对肝纤维化有望成为其早期诊断无创而有效的手段。现就DWI的成像方法及其对肝纤维化病理分级、分期等应用现状予以综述。     

磁共振扩散加权成像在肝外胆管癌诊断中的应用研究

目的探讨MR扩散加权成像(DWI)及表观扩散系数(apparent diffusion coefficient,ADC)值对肝外胆管癌的诊断价值。资料与方法回顾性分析58例经手术病理证实的肝外胆管癌患者的MRI原始资料,包括不同b值的DWI(b值为100 s/mm2、300 s/mm2、500 s/mm2、800 s/mm2、1000 s/mm2)及常规MRI平扫(T2WI、T1WI)。测量不同b值时肝外胆管癌病灶ADC值,计算病灶与正常肝脏间对比噪声比(CNR),根据HE染色病理图片记录肝外胆管癌细胞密度,并进行分析。结果 DWI对肝外胆管癌病灶的信号显示优于T2WI及T1WI。随着b值的增大,病灶ADC值逐渐降低,病灶与正常肝脏间CNR呈逐渐下降趋势,差异有统计学意义(P<0.05)。不同b值时,肝外胆管癌病灶ADC值与细胞密度之间均呈负相关(P<0.05);b=800 s/mm2时,其相关性最高(r=-0.81,P<0.05)。结论 DWI能较清楚地显示肝外胆管癌病灶,b值为800 s/mm2时最佳,与ADC值测量共同分析,有助于肝外胆管癌病灶的检出。     

Evaluation of therapeutic response to concurrent chemoradiotherapy in patients with cervical cancer using diffusion‐weighted MR imaging

Purpose:

To investigate the changes in apparent diffusion coefficients (ADCs) in cervical cancer patients receiving concurrent chemoradiotherapy (CCRT), and to assess the relationship between tumor ADCs or changes in tumor ADCs and final tumor responses to therapy.

Materials and Methods:

Twenty‐four patients with cervical cancer who received CCRT were examined with 3 Tesla (T) MRI including diffusion‐weighted imaging (DWI). All patients had three serial MR examinations: before therapy (pre‐Tx); at 4 weeks of therapy (mid‐Tx); and 1 month after completion of therapy (post‐Tx). At each examination, ADC was measured in tumors and normal gluteus muscles. Final tumor response as determined by change in tumor size or volume using MRI was correlated with tumor ADCs at each therapeutic time or changes in tumor ADCs at mid‐Tx.

Results:

From pre‐Tx to post‐Tx, mean tumor ADCs were 0.88, 1.30, and 1.47 × 10^?3 mm²/s in sequence (P < 0.001), while those of normal gluteus muscles were 1.24, 1.29, and 1.21 × 10^?3 mm²/s in sequence (P > 0.05). At mid‐Tx, tumor ADCs and changes in tumor ADCs had a significant correlation with final tumor size responses (P = 0.029 and 0.025, respectively). However, the tumor ADC values at pre‐Tx were not associated with the final tumor size response (P = 0.47). The final tumor volume response was not associated with tumor ADC at pre‐Tx or mid‐Tx (P > 0.05) or changes in tumor ADCs at mid‐Tx (P > 0.05).

Conclusion:

DWI may have potentials in evaluating the therapeutic response to CCRT in patients with cervical cancer. J. Magn. Reson. Imaging 2013;37:187–193. © 2012 Wiley Periodicals, Inc.

     

磁共振扩散加权成像在胰腺癌诊断中的价值

目的探讨磁共振扩散加权成像在胰腺癌诊断中的价值。方法选择2012年1月～2013年1月间临床可疑胰腺癌患者75例,对这些患者进行磁共振扩散加权成像检查,将检查结果与病理结果比较,明确两者之间的相关性,同时确定磁共振扩散加权成像在胰腺癌诊断中的敏感性、特异性。结果75例可疑胰腺癌患者经DWI检查,诊断为胰腺癌38例,与病理结果比较,两者存在相关性（r=23．12,P=-0．00〈0．05）,且相关系数为0．56。同时与病理结果比较DWI诊断胰腺癌的敏感性为73．33％,特异性为83．33％,阳性预测值和阴性预测值分别为86．84％和67．57％。结论磁共振扩散加权成像作为无创检查手段能够准确地对胰腺占位做出定性诊断,在临床应用价值较大。     

MRI 增强后扩散加权成像鉴别乳腺良恶性肿瘤临床应用研究

目的：评估乳腺疾病患者中钆对比剂对 MRI 扩散加权成像(DWI)和病变的表观扩散系数(ADC)是否有显著性影响,分析增强前后 ADC 值在乳腺良恶性病变鉴别中的价值。方法收集本院行乳腺 MRI 检查的35例患者共计38个病灶,所有病灶均经病理证实。笔者对比了增强前后正常乳腺组织及病灶的信噪比(SNR)和对比噪声比(CNR),以及病灶增强前后的 ADC 值。结果(1)增强前后 DWI 的 SNR 及 CNR 无统计学差异;(2)恶性病灶增强前后的 ADC 值存在统计学差异,增强前后 ADC 值平均降幅11.6%;良性病灶增强前后的 ADC 值无统计学差异。结论增强后 ADC 值能够更好地反映乳腺病变的恶性潜能。     

Diffusion-weighted magnetic resonance imaging in the characterization of axillary lymph nodes in patients with breast cancer

Purpose:

To assess prospectively the accuracy of diffusion‐weighted magnetic resonance imaging (DWI) in differentiating between metastatic and benign axillary lymph nodes in patients with breast cancer.

Materials and Methods:

In all, 215 patients with histologically proven breast cancer, prior to axillary dissection, underwent breast and axillary 1.5 T MRI. In 102 patients in whom at least one axillary lymph node with a short axis of 6 mm or more was found the apparent diffusion coefficient (ADC) was measured in one lymph node per patient by means of an echo planar, parallel imaging DWI sequence. Forty‐three lymph nodes were finally included which, on histological examination, either contained a metastasis larger than 5 mm or were metastasis‐free; nodes with metastases smaller than 5 mm were excluded.

Results:

From histological examination, 19/43 lymph nodes had a metastasis at least 5 mm, while in 24/43 no malignant cells were found. The ADC values of the lymph nodes with metastases (mean: 0.878 × 10^?3 mm²/s; range: 0.30 –1.20) were significantly lower (P < 0.001) than those of the benign lymph nodes (mean: 1.494; range: 0.60 –2.50). Adopting a threshold value of 1.09 × 10^?3 mm²/s DWI resulted in 94.7% sensitivity, 91.7% specificity, and 93.0% accuracy in the identification of metastasis in this series of lymph nodes.

Conclusion:

From these preliminary data DWI seems a promising method in the differential diagnosis between metastatic and benign axillary lymph nodes in patients with breast cancer. J. Magn. Reson. Imaging 2012;36:858–864. © 2012 Wiley Periodicals, Inc.

     

Diffusion‐weighted imaging of prostate cancer: Correlation between apparent diffusion coefficient values and tumor proliferation

Purpose

To investigate whether the apparent diffusion coefficient (ADC) values of prostate cancer (PCa) are able to reflect tumor proliferation.

Materials and Methods

The clinical and pathological information for 38 patients with PCa and 33 patients with benign prostate hyperplasia (BPH) were studied. Examination of the patients was performed using a 1.5 T superconducting magnetic scanner equipped with a pelvic phased‐array multicoil. Diffusion‐weighted images (DWIs) were acquired using an echo‐planar imaging sequence. The ADC values of PCa, BPH, and peripheral zone (PZ) were calculated. The cellularity of PCa was recorded based on hematoxylin and eosin staining. The proliferating cell nuclear antigen (PCNA) was detected using an immunohistochemical technique.

Results

The ADC values of PCa, BPH, and PZ were 49.32 ± 12.68 × 10^?5 mm²/s, 86.73 ± 26.75 × 10^?5 mm²/s, and 126.25 ± 27.21 × 10^?5 mm²/s, respectively. The ADC values of PCa were lower than those of BPH and PZ (P < 0.05). The cellularity and PCNA labeling index (LI) of PCa were higher than those of BPH (P < 0.05). The ADC values of PCa were negatively correlated with those of cellularity and PCNA LI (r = ?0.646 and ?0.446, respectively; P < 0.05).

Conclusion

The ADC values of PCa can reveal the differences in proliferative activity between PCa and BPH. These values are therefore able to predict the proliferative rate of variously differentiated prostate cancers. J. Magn. Reson. Imaging 2009;29:1360–1366. © 2009 Wiley‐Liss, Inc.

     

MR DWI对急性胰腺炎的诊断价值

目的 探讨MR扩散加权成像(DWI)对急性胰腺炎(AP)的诊断价值.方法 回顾性分析50例AP及75例正常胰腺的MR资料,计算DWI序列b=800 s/mm2图像上胰腺与肝脏的信号强度比(SIR),测量胰腺的表观扩散系数(ADC),分别比较2组的SIR及ADC,并根据受试者工作特征(ROC)曲线确定最佳诊断阈值,评价SIR、ADC与MRI常规序列的诊断效能.结果 与正常胰腺相比,AP组SIR显著升高(2.06±0.48 vs 1.24±0.27,t=12.2,P<0.0001),ADC显著降低[(991±133)μm2/s vs(1153±149)μm2/s,t=-6.2,P<0.0001].最佳诊断阈值分别为SIR>1.51、ADC≤1039μm2/s.SIR的敏感度(92.0%)高于ADC(72.0%)及MRI常规序列(74.0%),SIR(88.0%)及MRI常规序列(93.3%)的特异度高于ADC(77.3%).结论 AP时水分子扩散受限,SIR诊断效能优于ADC及MRI常规序列,有利于AP的检出.