磁共振波谱成像对中央腺体前列腺癌与良性增生结节的鉴别诊断

Objective To explore the metabolic characteristic of prostate cancer (PCa) in central gland with magnetic resonance (MR) spectroscopic, and evaluate the value of MRS in the differential diagnosis of benign prostatic hyperplasia nodus. Methods MR images were performed in 38 cases with prostate disease by 3.0T MR, 11 cases with PCa in central gland and 27 cases with benign prostatic hyperplasia nodus. All the cases were scanned by routine, then by the combined MRS. MRS findings were reviewed in 27 cases with benign prostatic hyperplasia (BPH) and 11 cases with PCa (3 in central gland origin, 8 with large tumor invading both peripheral zone and central gland). (Cho+Cr)/Cit ratios of PCa and BPH were retrospectively measured, (Cho+Cr)/Cit of PCa voxels were compared with that of BPH voxels. Results Significantly higher choline levels and lower citrate levels were observed in central gland of PCa compared with BPH. In the glandular BPH region, the amount of Cit was high; while in the stromal region, the Cit and Cho level was much lower. The average (Cho+Cre)/Cit values of PCa and BHP were 1.94±1.43 and 0. 83±0. 28 respectively, the difference in ratio between both was statistically significant (P＜0. 01). Conclusions The combined use of MRI and MR spectroscopy is propitious for differentiating prostate cancer in central gland and benign prostatic hyperplasia nodus and for increasing the diagnostic accuracy of prostate cancer.     

Diffusion-weighted magnetic resonance imaging without bowel preparation for detection of ulcerative colitis

AIM: To evaluate the accuracy of diffusion-weighted imaging(DWI) without bowel preparation,the optimal b value and the changes in apparent diffusion coefficient(ADC) in detecting ulcerative colitis(UC).METHODS: A total of 20 patients who underwent 3T magnetic resonance imaging(MRI) without bowel preparation and colonoscopy within 24 h were recruited.Biochemical indexes,including C-reactive protein(CRP),erythrocyte sedimentation rate,hemoglobin,leucocytes,platelets,serum iron and albumin,were determined.Biochemical examinations were then performed within 24 h before or after MR colonography was conducted.DWI was performed at various b values(b = 0,400,600,800,and 1000 s/mm2).Two radiologists independently and blindly reviewed conventional- and contrast-enhanced MR images,DWI and ADC maps; these radiologists also determined ADC in each intestinal segment(rectum,sigmoid,left colon,transverse colon,and right colon).Receiver operating characteristic(ROC) analysis was performed to assess the diagnostic performance of DWI hyperintensity from various b factors,ADC values and different radiological signs to detect endoscopic inflammation in the corresponding bowel segment.Optimal ADC threshold was estimated by maximizing the combination of sensitivity and specificity.MRfindings were correlated with endoscopic results and clinical markers; these findings were then estimated by ROC analysis.RESULTS: A total of 100 segments(71 with endoscopic colonic inflammation; 29 normal) were included.The proposed total magnetic resonance score(MR-score-T) was correlated with the total modified Baron score(Baron-T; r = 0.875,P 0.0001); the segmental MR score(MR-score-S) was correlated with the segmental modified Baron score(Baron-S; r = 0.761,P 0.0001).MR-score-T was correlated with clinical and biological markers of disease activity(r = 0.445 to 0.831,P 0.05).MR-score-S 1 corresponded to endoscopic colonic inflammation with a sensitivity of 85.9%,a specificity of 82.8% and an area under the curve(AUC) of 0.929(P 0.0001).The accuracy of DWI hyperintensity was significantly greater at b = 800 than at b = 400,600,or 1000 s/mm2(P 0.05) when endoscopic colonic inflammation was detected.DWI hyperintensity at b = 800 s/mm2 indicated endoscopic colonic inflammation with a sensitivity of 93.0%,a specificity of 79.3% and an AUC of 0.867(P 0.0001).Quantitative analysis results revealed that ADC values at b = 800 s/mm2 differed significantly between endoscopic inflamed segment and normal intestinal segment(1.56 ± 0.58 mm2/s vs 2.63 ± 0.46 mm2/s,P 0.001).The AUC of ADC values was 0.932(95% confidence interval: 0.881-0.983) when endoscopic inflammation was detected.The threshold ADC value of 2.18 × 10-3 mm2/s indicated that endoscopic inflammation differed from normal intestinal segment with a sensitivity of 89.7% and a specificity of 80.3%.CONCLUSION: DWI combined with conventional MRI without bowel preparation provides a quantitative strategy to differentiate actively inflamed intestinal segments from the normal mucosa to detect UC.     

Predicting liver metastasis of gastrointestinal tract cancer by diffusion-weighted imaging of apparent diffusion coefficient values

AIM: To determine if efficacy of chemotherapy on liver metastasis of gastrointestinal tract cancer can be predicted by apparent diffusion coefficient(ADC) values of diffusion-weighted imaging(DWI). METHODS: In total, 86 patients with liver metastasis of gastrointestinal tract cancer(156 metastatic lesions) diagnosed in our hospital were included in this study. The maximum diameters of these tumors were compared with each other before treatment, 2 wk after treatment, and 12 wk after treatment. Selected patients were classified as the effective group and the ineffective group, depending on the maximum diameter of the tumor after 12 wk of treatment; and the ADC values at different treatment times between the two groups were compared. Spearman rank correlation was used to analyze the relationship between ADC value and tumor diameter. Receiver operating characteristic curve(ROC curve) was used to analyze the ADC values before treatment to predict the patient's sensitivity and specificity degree of efficacy to the chemotherapy. RESULTS: There was no difference in age between the two groups and in maximum tumor diameter before treatment and 2 wk after treatment. However, after 12 wk of treatment, maximum tumor diameter in the effective group was significantly lower than that in the ineffective group(P 0.05). Before treatment, ADC values in the ineffective group were significantly higher than those in the effective group(P 0.05). There was no difference in ADC values between the effective and ineffective groups after 2 and 12 wk of treatment. However, ADC values were significantly higher after 2 and 12 wk of treatment compared to before treatment in the effective group(P 0.05). Spearman rank correlation analysis showed that ADC value before treatment and the reduced percentage of the maximum tumor diameter after 12 wk of treatment were negatively correlated, while the increase in the percentage of the ADC value 12 wk after treatment and the decrease in the percentage of the maximum tumor diameter were significantly positively correlated. The results of the ROC curve showed that ADC value with a chemotherapy ineffective threshold value of 1.14 × 10-3 mm2/s before treatment had a sensitivity and specificity of 94.3% and 76.7%, respectively. CONCLUSION: DWI ADC values can be used to predict the response of patients with liver metastasis of gastrointestinal tract cancer to chemotherapy with high sensitivity and relatively high specificity.     

Importance of b value in diffusion weighted imaging for the diagnosis of pancreatic cancer

AIM:To investigate the use of multi-b-value diffusionweighted imaging in diagnosing pancreatic cancer.METHODS:We retrospectively analyzed 33 cases of pancreatic cancer and 12 cases of benign pancreatic tumors at the Second Affiliated Hospital of Kunming Medical University from December 2008 to January2011.The demographic characteristics,clinical presentation,routine magnetic resonance imaging and diffusion weighted imaging(DWI)features with different b values were reviewed.Continuous data were expressed as mean±SD.Comparisons between pancreatic cancer and benign pancreatic tumors were performed using the Student’s t test.A probability of P<0.05 was considered statistically significant.RESULTS:Thirty-three patients with pancreatic cancer were identified.The mean age at diagnosis was 60±5.6 years.The male:female ratio was 21:12.Twenty cases were confirmed by surgical resection and 13 by biopsy of metastases.T1 weighted images demonstrated a pancreatic head mass in 16 patients,a pancreatic body mass in 10 cases,and a pancreatic tail mass with pancreatic atrophy in 7 cases.Eight patients had hepatic metastases,13 had invasion or envelopment of mesenteric vessels,4 had bone metastases,and 8had lymph node metastases.DWI demonstrated an irregular intense mass with unclear margins.Necrotic tissue demonstrated an uneven low signal.A b of 1100s/mm2was associated with a high intensity signal with poor anatomical delineation.A b of 700 s/mm2was associated with apparent diffusion coefficients(ADCs)that were useful in distinguishing benign and malignant pancreatic tumors(P<0.05).b values of 50,350,400,450 and 1100 s/mm2were associated with ADCs that did not differentiate the two tumors.CONCLUSION:Low b value images demonstrated superior anatomical details when compared to high b value images.Tumor tissue definition was high and contrast with the surrounding tissues was good.DWI was useful in diagnosing pancreatic cancer.     

磁共振弥散加权成像对胰腺癌与慢性肿块型胰腺炎的鉴别诊断价值

目的 比较磁共振弥散加权成像(diffusion-weighted imaging,DWI)对胰腺癌与慢性肿块型胰腺炎的鉴别能力.方法 对38例胰腺癌、9例肿块型CP、15例正常胰腺行DWI.在x、Y、Z轴3个方向上选择3个不同弥散系数(b=0、500、1 000 s/mm2)进行扫描,共行2次DWI.根据表观弥散系数(apparent diffusion coefficient,ADC)图像测量ADC值.结果 38例胰腺癌平均ADC值为(1.411±0.101)×10m-3mm2/s,9例肿块型CP的平均ADC值为(1.053±0.113)×10-3mm2/s,15例正常胰腺平均ADC值为(1.245±0.112)×10-3mm2/s,两两比较均有统计学意义(P＜0.05).结论 DWI可对胰腺癌与肿块型CP进行鉴别诊断,具有较大的临床意义.     

Magnetic resonance-based total liver volume and magnetic resonance-diffusion weighted imaging for staging liver fibrosis in mini-pigs

AIM:To determine whether and how magnetic resonance imaging(MRI)-based total liver volume(TLV) and diffusion weighted imaging(DWI) could predict liver fibrosis.METHODS:Sixteen experimental mature mini-pigs(6 males,10 females),weighing between 20.0 and 24.0 kg were prospectively used to model liver fibrosis induced by intraperitoneal injection of 40% CCl4 dissolved in fat emulsion twice a week for 16 wk,and by feeding 40% CCl4 mixed with maize flour twice daily for the subsequent 5 wk.All the survival animals underwent percutaneous liver biopsy and DWI using b = 300,500 and 800 s/mm2 followed by abdominal gadolinium-enhanced MRI at the 0,5th,9th,16th and 21st weekend after beginning of the modeling.TLV was obtained on enhanced MRI,and apparent diffusion coefficient(ADC) was obtained on DWI.Hepatic tissue specimens were stained with hematoxylin and Masson' s trichrome staining for staging liver fibrosis.Pathological specimens were scored using the human METAVIR classification system.Statistical analyses were performed to determine whether and how the TLV and ADC could be used to predict the stage of liver fibrosis.RESULTS:TLV increased from stage 0 to 2 and decreased from stage 3(r = 0.211;P 0.001).There was a difference in TLV between stage 0-1 and 2-4(P = 0.03) whereas no difference between stage 0-2 and 3-4(P = 0.71).TLV could predict stage ≥ 2 [area under receiver operating characteristic curve(AUC) = 0.682].There was a decrease in ADC values with increasing stage of fibrosis for b = 300,500 and 800 s/mm2(r =-0.418,-0.535 and-0.622,respectively;all P 0.001).Differences were found between stage 0-1 and 2-4 in ADC values for b = 300,500 and 800 s/mm2,and between stage 0-2 and 3-4 for b = 500 or 800 s/mm2(all P 0.05).For predicting stage ≥ 2 and ≥ 3,AUC was 0.803 and 0.847 for b = 500 s/mm2,and 0.848 and 0.887 for b = 800 s/mm2,respectively.CONCLUSION:ADC for b = 500 or 800 s/mm2 could be better than TLV and ADC for b = 300 s/mm2 to pre-dict fibrosis stage ≥ 2 or ≥ 3.     

Value of MR diffusion imaging in hepatic fibrosis and its correlations with serum indices

AIM:To compare apparent diffusion coefficient(ADC)values on diffusion-weighted imaging(DWI)of hepatic fibrosis patients with those of healthy controls and to identify their correlations with serum indices of liver fibrosis.METHODS:Hyaluronic acid(HA),laminin(LN),typeⅢprocollagen(PCⅢ),and collagen typeⅣ(Ⅳ-C)were measured in 54 hepatic fibrosis patients and 23normal controls,and ADC values were determined on DWI at different b values(b=300,500,700 s/mm2).Correlations between serum indices and ADC values at different liver fibrosis stages were examined,and each index variation of liver fibrosis in different stages were compared,and correlation analysis of each index and the staging of liver fibrosis carried out,and the correlation of each index performed.RESULTS:With progressive liver fibrosis,HA,PCⅢ,andⅣ-C levels increased(P<0.01).As the b value increased,the ADC value decreased gradually with the hepatic fibrosis stages.In different groups with b values of 500 s/mm2 and 700 s/mm2,the ADC value decreased significantly as liver fibrosis progressed(P<0.01).With b values of 500 s/mm2 and 700 s/mm2,there were negative correlations between ADC and LN,PCⅢ,HA,andⅣ-C.This pattern was observed only for HA andⅣ-C at a b value of 300 s/mm2.CONCLUSION:Serum indices of liver fibrosis and ADC values are useful for diagnosing liver fibrosis,with some correlations among them.     

酶联免疫吸附法测定血小板反应素1及其对前列腺癌诊断价值的研究

Objective To use enzyme-linked immunosorbent assay (ELISA) for measuring thrombospondin-1 (TSP-1),and to analyze its diagnostic value for prostatic carcinoma.Methods The possible difficulties and the way to solve the difficulties with ELISA spot were explored first.Three agents which could segregate idio-antigen and one technique which could depurate proteinum were designed and developed.The non- idio- proteinum cross reaction problems were solved and the routine method to measure TSP-1 with ELISA was set up successfully.The serum TSP-1 was measured in 14 patients with benign prostatic hyperplasia (BPH) and 18 patients with prostatic carcinoma.Results The TSP-1 values were (73.77±12.72)% and (121.86±-19.47)% in prostatic carcinoma group and benign prostatic hyperplasia group,respectively (t= 8.44,P＜0.01).The diagnostic sensitivity and specificity of TSP-1 and prostate specific antigen (PSA) for prostatic cancer were 92.7%,88.9% and 85.7%,66.7%,respectively (P＜0.01).The area under the receiver operating characteristic curve (ROC) of TSP-1 and PSA were 0.9663 and 0.7421 (P＜0.05).Conclusions The determination of TSP-1 with ELISA is feasible.TSP-1 is an ideal diagnostic parameter for prostatic carcinoma and it may distinguish BPH from malignant prostatic disease more exactly than PSA.     

Quantitative diffusion-weighted magnetic resonance enterography in ileal Crohn's disease: A systematic analysis of intra and interobserver reproducibility

BACKGROUND Magnetic resonance enterography(MRE) is increasingly attractive as a noninvasive and radiation-free tool for assessing Crohn's disease(CD). Diffusionweighted imaging(DWI) is recommended as an optional MRE sequence for CD by the European Society of Gastrointestinal and Abdominal Radiology, and has shown a superb potential as a quantitative modality for bowel inflammation evaluation. However, the measurement reproducibility of quantitative DWI analysis in MRE has not been ascertained so far. To facilitate the application of quantitative diffusion-weighted MRE in the clinical routine, systematic investigations of the intra and interobserver reproducibility of DWI quantitative parameters should be performed.AIM To evaluate the intra and interobserver reproducibility of quantitative analysis for diffusion-weighted MRE(DW-MRE) in ileal CD.METHODS Forty-four subjects(21 with CD and 23 control subjects) who underwent ileocolonoscopy and DW-MRE(b = 800 s/mm2) within one week were included.Two radiologists independently measured apparent diffusion coefficients(ADC)of the terminal ileum and signal intensity ratio(SR) of the terminal ileum to ipsilateral psoas muscle on DWI images(b = 800 s/mm2). Between-and withinreader agreements were assessed using intraclass correlation coefficients(ICC),coefficients of variation(CoV), and 95% limits of agreement of Bland-Altman plots(BA-LA LoA). Diagnostic performances of ADC and SR for identifying inflamed terminal ileum from the normal were evaluated by receiver operating characteristic(ROC) curve analysis.RESULTS There were no significant differences in ADC or SR values between the two sessions or between the two radiologists either in the CD or control group(paired t-test, P 0.05). The intra and interobserver reproducibility of ADC(ICC: 0.952-0.984; CoV: 3.73-6.28%; BA-LA LoA: ±11.27% to ±15.88%) and SR(ICC: 0.969-0.989; CoV: 3.51%-4.64%; BA-LA LoA: ±10.62% to ±15.45%) was excellent for CD.Agreement of ADC measurements was slightly less in control subjects(ICC:0.641-0.736; CoV: 10.47%-11.43%; BA-LA LoA: ± 26.59% to ± 30.83%). SR of normal terminal ileum demonstrated high intra and interobserver reproducibility(ICC: 0.944-0.974; CoV: 3.73%-6.28%; BA-LA LoA: ± 18.58% to ± 24.43%). ADC and SR of two readers had outstanding diagnostic efficiencies(area under the ROC curve: 0.923-0.988).CONCLUSION Quantitative parameters derived from DW-MRE have good to excellent intra and interobserver agreements with high diagnostic accuracy, and can serve as robust and efficient quantitative biomarkers for CD evaluation.     

人类表皮生长因子受体2蛋白及雄激素受体在前列腺癌中的表达及其意义

目的 检测Her-2/neu蛋白和雄激素受体(androgen receptor,AR)在前列腺癌组织中的表达情况,探讨其在前列腺癌发生发展中的意义.方法 构建前列腺病变的组织芯片,其中包括前列腺癌107例(Gleason评分6分29例,7分20例,8分46例,9分12例),良性前列腺组织42例;采用EnVsion两步法进行Her-2/neu蛋白和AR的免疫组织化学染色,分析其在前列腺癌及良性前列腺组织中的差异;从免疫组织化学染色强度及阳性细胞数两个方面评价蛋白表达情况,分析其与前列腺癌Gleason评分的关系.结果 Her-2/neu蛋白在前列腺癌组织中的阳性表达率为43.9%,高于在良性前列腺组织中的阳性表达率(14.3%)(x2=11.562,P=0.009),其阳性表达强度前列腺癌高于良性前列腺组织(x2=11.764,P=0.008).在不同Gleason评分组中,Her-2/neu蛋白的阳性表达强度差异有统计学意义(x2=20.512,P=0.015),且与Gleason评分呈正相关(r=0.269,P=0.005).前列腺癌组织AR阳性表达率(67%)高于良性前列腺组织(50%)(x2=3.843,P=0.050),但其阳性表达强度在前列腺癌及良性前列腺组织中的差异无统计学意义(x2=4.318,P=0.229).在不同Gleason评分组中AR的阳性表达强度差异无统计学意义(x2=13.385,P=0.146),与Gleason评分无相关性(r=-0.065,P=0.505).前列腺癌组织中Her-2/neu蛋白和AR的阳性表达强度无相关性(r=-0.115,P=0.237).结论Her-2/neu蛋白在前列腺癌中的高表达提示其可能在前列腺癌发生中起一定作用.Her-2/neu蛋白的阳性表达强度与Gleason评分呈正相关,提示Her-2/neu蛋白与前列腺癌的预后有一定的相关性.

Abstract：

Objective To observe the expression of Her-2/neu protein and androgen receptor (AR) in human prostate cancer and to evaluate their significances in the progression of prostate cancer. Methods The Her-2/neu protein and AR immunohistochemical stain were carried out in human prostate tissue microarray that consisted of prostate cancer (107 cases) and benign prostate tissue (42 cases). The prostate cancer cases were divided into 4 groups: group one (Gleason score 6),group two (Gleasonscore 7), group three (Gleasonscore 8) and group four (Gleasonscore 9) according to the Gleason score. The immunostains immunohistochemical stain were interpreted in two aspects of the staining intensity and the percentage of positive cells. The significance and relationships between the expression of Her-2/neu protein and AR in prostate cancer and benign prostate tissue (BPT) and the grouping of different Gleason scores of prostate cancer were then evaluated. Results The positive expression rate of Her-2/neu protein was significantly higher in prostate cancer tissue than in BPT [43.9%(47/107) vs. 14.3%(6/42), x2=11.562, P=0.009], and the positive expression intensity of Her-2/neu immunoreactivity was also higher (x2= 11.764, P=0.008). There were significant differences in positive expression intensity of Her-2/neu immunoreactivity among the different Gleason scores groups (x2 = 20. 512, P = 0. 015), and the expression intensity was significantly positively correlated with Gleason scores ( r= 0. 269, P = 0. 005). There was significant difference in AR immunoreactivity between in prostate cancer (67 %, 72/107) and in BPT (50 %, 21/42, x2 =3. 843, P=0. 050). Among prostate cancer cases, the positive expression intensity of AR was not significantly different among groups 1 through 4 (x2 = 4. 318, P = 0. 229), and was not significantly correlated with Gleason scores ( r = - 0. 065, P = 0. 505 ). Moreover, the positive expression intensity of Her-2/neu protein was not significantly correlated with that of AR (r = -0. 115, P=0. 237). Conclusions Overexpression of Her-2/neu protein in human prostate cancer tissue suggests that Her-2/neu may have some role in prostate tumorigenesis. Her-2/neu protein expression is positively correlated with Gleason score in prostate cancer, which suggests that Her-2/neu may be a potential prognostic predictor of prostate cancer.     

磁共振扩散加权成像在胰腺囊性病变中的鉴别诊断价值

目的 评价磁共振扩散加权成像（DWI）在胰腺囊性病变中的鉴别诊断价值.方法 收集经临床和（或）病理证实的34例胰腺囊性病变,包括非肿瘤性病变的假性囊肿11例、单纯囊肿5例,肿瘤性病变的浆液性囊腺瘤6例、黏液性囊腺瘤10例、黏液性囊腺癌2例.34例均行常规MRI平扫及动态增强、DWI（b值0,600 s/mm2）扫描,记录病变DWI信号特点,测量病变及毗邻胰腺实质表观扩散系数（ADC）值,计算病变-胰腺实质ADC值比（ADCR）.采用受试者工作特征（ROC）曲线评价病灶ADC值及ADCR的诊断价值.结果 16例非肿瘤性囊性病变组中2例DWI上呈稍高信号,14例呈等信号,18例肿瘤性囊性病变组中17例呈高或稍高信号,l例呈等信号,两组差异具有统计学意义（P ＜0.001）.非肿瘤性、肿瘤性囊性病变的ADC值分别为（3.30 ±0.30）×10-3、（2.74±0.34）×10-3mm2/s;ADCR分别为1.85 ±0.20、1.31 ±0.21,差异均具有统计学意义（P值均＜0.001）.ADC值及ADCR诊断胰腺肿瘤性囊性病变的ROC曲线下面积分别为0.94±0.04、0.98±0.02.ADC值以3.105×10-3 mm2/s为阈值,诊断肿瘤性囊性病变的敏感性为81.3％,特异性为94.4％,ADCR值以1.525为阈值,诊断肿瘤性囊性病变的敏感性为100％,特异性为88.9％.结论 DWI在胰腺囊性病变的诊断与鉴别诊断中具有重要价值,可作为常规MRI的重要补充.     

扩散加权成像技术在肝脏囊性病变中的应用

目的探讨MR扩散加权成像(DWI)及表观扩散系数(ADC)值在肝脏囊性病变诊断中的价值。方法对50例肝囊性病变患者行DWI检查,并测量ADC值。包括单纯性肝囊肿15例、单房囊肿型肝包虫病15例、脓腔形成期肝脓肿10例、囊性坏死性肝转移瘤10例。结果单纯性肝囊肿、单房囊肿型肝包虫病、脓腔形成期肝脓肿、囊性坏死性肝转移瘤ADC值分别为(3.85±0.23)×10-3 mm2/s、(3.52±0.53)×10-3 mm2/s、(1.069±0.1)×10-3 mm2/s、(2.159±0.14)×10-3 mm2/s,单纯性肝囊肿、单房囊肿型肝包虫病、脓腔形成期肝脓肿、囊性坏死性肝转移瘤ADC值差异有统计学意义(P<0.05)。在DWI图像上,脓腔形成期肝脓肿、囊性坏死性肝转移瘤呈高信号,而单纯性肝囊肿、单房囊肿型肝包虫病均呈低信号。结论分析DWI图像特点及ADC值在肝脏囊性病变中的鉴别诊断有重要价值。     

磁共振扩散加权成像鉴别诊断胰腺神经内分泌肿瘤和胰腺癌

目的 探讨磁共振扩散加权成像(DWI)及其表观弥散系数(ADC)在胰腺神经内分泌肿瘤与胰腺癌鉴别诊断中的应用价值.方法 回顾性分析经病理证实的17例神经内分泌肿瘤及16例胰腺癌患者的DWI检查结果(弥散敏感因子b值取0和800 s/mm2),在ADC图上测量肿瘤的最小ADC值,采取非参数检验对所得数据进行统计学检验...     

应用MRI弥散成像表观弥散系数监测肝转移瘤化疗疗效研究

目的评估应用磁共振弥散加权成像表观弥散系数（ADC）预测和早期监测肝转移瘤化疗疗效的可行性。方法选择43例原发肿瘤为胃肠道、乳腺或其他部位的肝转移瘤患者,在化疗前和化疗后2~3周常规检查弥散加权成像并获得相应的ADC值。采用RECIST作为评价肝转移肿瘤化疗疗效的标准。结果在43例肝转移瘤68个病灶中,30个病灶对化疗有效,38个病灶对化疗无效,其治疗前平均ADC值分别为1.22±0.39×10-3mm2/s和1.54±0.55×10-3mm2/s（P=0.008）;在治疗后2周,化疗有效组ADC值升至1.43×10-3mm2/s（P=0.005）,而化疗无效则降至1.23×10-3mm2/s（P=0.13）;以ADC值=1.50×10-3mm2/s为治疗有效或无效的临界点,其判断疗效的阳性预测值为94%,阴性预测值为92%,准确率为93%。结论磁共振弥散加权成像ADC可作为预测肝转移瘤化疗疗效的影像学指标。     

高场磁共振多b值弥散加权成像鉴别诊断肝血管瘤与肝细胞癌价值探讨*

目的 探讨高场磁共振多b值弥散加权成像(DWI)鉴别诊断肝血管瘤(HH)与肝细胞癌(HCC)的价值。方法 2019年6月～2021年5月我院收治的85例肝脏局灶性占位性病变(FLL)患者,均接受高场MRI检查,记录不同b值下表观扩散系数(ADC)。均接受肝叶切除术,行组织病理学检查。绘制受试者工作特征(ROC)曲线,以曲线下面积(AUC)评估ADC的鉴别诊断价值。结果 在85例FLL患者中,术后组织病理学检查诊断为HH者28例(32.9%)、肝局灶性结节性增生( FNH)者18例(21.2%)和肝细胞癌(HCC)者39例(45.9%);在b值=50 s/mm²、b值=400 s/mm²和b值=1000 s/mm²时,HCC病灶ADC值分别为(2.41±0.20)×10^-3/mm²/s、(2.02±0.19)×10^-3/mm²/s和(1.73±0.15)×10^-3/mm²/s,FNH病灶分别为(2.43±0.31)×10^-3/mm²/s、(2.05±0.21)×10^-3/mm²/s和(2.01±0.18)×10^-3/mm²/s,均显著低于HH病灶【分别为(2.63±0.35)×10^-3/mm²/s、(2.46±0.32)×10^-3/mm²/s和(2.25±0.23)×10^-3/mm²/s,P＜0.05】;根据b值=1000 s/mm²时HH与HCC病灶ADC值绘制ROC曲线,结果显示,以高场磁共振ADC=1.73×10^-3/mm²/s为最佳截断点,其鉴别HH与HCC的AUC(95%CI)为0.727(0.581～0.844,P＜0.05),约登指数为0.559,其灵敏度为80.0%,特异度为75.9%。结论 采用高场磁共振DWI鉴别诊断HH与HCC病灶具有很大的临床价值,我们推荐应用b值为1000s/mm²时高场磁共振DWI可能鉴别诊断价值更高。     

3.0T磁共振弥散加权成像在肝脏局灶性病变中的诊断价值初探

目的初步探讨3.0T磁共振弥散加权成像（DWI）对肝脏局灶性病变的鉴别诊断价值。方法采用GE 3.0T Signal EXCITE超导型磁共振扫描系统对65例共68个病灶患者行DWI,并分析病灶信号特征。肝囊肿13个病灶,肝血管瘤12个病灶,炎性假瘤4个病灶,局灶性结节性增生（FNH）5个病灶;肝细胞癌13个病灶,转移瘤21个病灶。应用弥散敏感系数b值0、500、1000 s/mm2的图像拟合出ADC图并测量ADC值。结果肝囊肿、血管瘤、炎性假瘤、FNH、肝细胞癌、转移瘤平均ADC值（×10-3mm2/s）分别为3.34±0.45、2.07±0.35、1.59±0.16、1.50±0.18、1.25±0.31、1.04±0.20;肝囊肿、血管瘤与其它病灶平均ADC之间差异均有统计学意义（P〈0.05）。随着b值的增加,肝囊肿信号衰减最明显,肝细胞癌、转移瘤信号衰减不明显。结论 3.0T磁共振弥散加权成像及其定量ADC值对肝脏占位病变的鉴别诊断具有重要的临床价值。     

磁共振弥散加权成像在肝硬化诊断中的应用

目的探讨磁共振弥散加权成像对肝硬化的诊断价值。方法采用GEHDx1．5TMRI扫描仪对100例临床诊断肝硬化患者（肝硬化组）及30名健康对照者（对照组）行轴位屏气弥散加权成像扫描（扩散敏感系数b值选用800mm^2／s）,比较2组表观弥散系数（apparent diffusion coefficient。ADC）值。结果对照组与肝硬化组肝脏ADC值分别为（1．842±0．173）和（1．380±0．137）×10^-3mm^2/s,后者低于前者,2组差异有统计学意义。结论肝硬化患者肝脏ADC值下降,磁共振弥散加权成像可望成为无创肝硬化诊断的手段之一。     

磁共振弥散加权成像对急性胰腺炎严重性分级的诊断价值

目的 探讨磁共振弥散加权成像（DWI）及表观弥散系数（ADC）值对急性胰腺炎（AP）严重性分级的诊断价值.方法 收集57例AP及13例正常胰腺含有DWI的磁共振成像（MRI）资料.参照Balthazar CT分级标准,将AP的MRI表现分为相应的A、B、C、D、E5级,测量炎症胰腺及正常胰腺的ADC值.应用单因素方差分析（ANOVA）对各级别AP之间、各级别与正常胰腺之间的ADC值进行统计学分析.结果 57例AP的MRI分为A级6例,B级9例,C级11例,D级10例,E级21例.炎症胰腺在DWI图像均呈高信号（100％）.A、B、C、D、E级AP的平均ADC值分别为（1.138 ±0.024）、（1.289±0.179）、（1.513 ±0.156）、（1.554 ±0.248）、（1.938±0.567） ×10-3 mm2/s,正常胰腺的ADC值为（1.687±0.129）×10-3mm2/s.A、B级AP的ADC值显著低于E级（P值均＜0.01）及正常胰腺（P值均＜0.05）,C级的ADC值低于E级（P＜0.05）,其余各级别之间,C、D、E级与正常胰腺之间的ADC值差异均无统计学意义（P值均＞0.05）.结论 磁共振DWI有利于Balthazar分级中形态变化不明显的A级及B级AP的早期诊断,但ADC值对AP严重性的分级诊断无明显价值.     

Role of diffusion-weighted magnetic resonance imaging in the diagnosis of extrahepatic cholangiocarcinoma

AIM: To determine the clinical value of diffusion-weight- ed imaging (DWI) for the diagnosis of extrahepatic cholangiocarcinoma (EHCC) by comparing the diagnostic sensitivity of DWI and magnetic resonance cholan-giopancreatography (MRCP). METHODS: Magnetic resonance imaging examination was performed in 56 patients with suspected EHCC. T1- weighted imaging, T2-weighted imaging, MRCP and DWI sequence, DWI using single-shot spin-echo echoplanar imaging sequence with different b values (100, 300, 500, 800 and 1...