The usefulness of diffusion-weighted magnetic resonance imaging （DWI） in the evaluation of scrotal pathology has recently been reported. A standard reference of normal testicular apparent diffusion coefficient （ADC...The usefulness of diffusion-weighted magnetic resonance imaging （DWI） in the evaluation of scrotal pathology has recently been reported. A standard reference of normal testicular apparent diffusion coefficient （ADC） values and their variations with age is necessary when interpreting normal testicular anatomy and pathology. We evaluated 147 normal testes using DWI, including 71 testes from 53 men aged 20-39years （group 1）, 67 testes from 42 men aged 40-69 years （group 2） and nine testes from six men older than 70years （group 3）. DWI was performed along the axial plane, using a single shot, multislice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s mm-2. The mean and standard deviation of the ADC values of normal testicular parenchyma were calculated for each age group separately. Analysis of variance （ANOVA） followed by post hoc analysis （Dunnett T3） was used for statistical purposes. The ADC values （x 10-3 mm2s-1） of normal testicular tissue were different among age groups （group 1：1.08 ± 0.13; group 2：1.15 ±0.15 and group 3：1.31± 0.22）. ANOVA revealed differences in mean ADC among age groups （F= 11.391, P〈 0.001）. Post hoc analysis showed differences between groups 1 and 2 （P= 0.008） and between groups 1 and 3 （P= 0.043）, but not between groups 2 and 3 （P= 0.197）. Our findings suggest that ADC values of normal testicular tissue increase with advancing age.展开更多
Purpose: Commonly used diffusion weighted (DW) imaging such as DW spin echo (SE) type echo planar imaging (DW-SE-EPI) is known to be a snapshot-like acquisition and to have a relatively high signal-to-noise ratio. Spi...Purpose: Commonly used diffusion weighted (DW) imaging such as DW spin echo (SE) type echo planar imaging (DW-SE-EPI) is known to be a snapshot-like acquisition and to have a relatively high signal-to-noise ratio. Spiral MRI sequence (SPIRAL) has characteristics similar to these of EPI, but it has rarely been used for diffusion-weighted imaging (DWI). In vivo DW-SPIRAL of the rat brain has almost never been reported. Our purpose in this study was to examine the potential of SE-type two-dimensional (2D) multi-shot spiral acquisition MRI for apparent diffusion coefficient (ADC) mapping of the rat brain in vivo. Materials and Methods: We made an SE-type DW-2D-spiral MRI sequence (DW-SPIRAL) which was prepared on a 2.0-T animal-experiment MR scanner. Comparing the phantom experimental result of DW-SPIRAL with the phantom experimental result of DW SE-type echo-planar imaging (DW-SE-EPI) and conventional DW spin echo imaging (DW-SE), we estimated the characteristics of DW-SPIRAL and assessed the clinical application of DW-SPIRAL in an animal experiment on the rat brain. Results: There was not much difference between the calculated water/glycerol phantom diffusion coefficient of DW-SPIRAL and the calculated diffusion coefficient of DW-SE. This result shows that the DW-SPIRAL sequence is appropriate for use in diffusion weighted imaging. There were fewer phantom image distortions and ghosting artifacts with DW-SPIRAL than with DW-SE-EPI, and this tendency was similar in the animal experiment on the rat brain. Conclusion: The DW-SPIRAL sequence had been successfully tested in phantom experiments and rat brain experiments. It has been demonstrated that the DW-SPIRAL sequence is capable of producing in vivo rat brain DWI.展开更多
目的探析T2加权成像(T_(2)WI)联合扩散加权成像(DWI)用于直肠诊断及术前分期的效能及其相对表观扩散系数(rADC)、表观扩散系数(ADC)值与患者临床特征的相关性。方法选择疑似直肠癌患者212例,其中男性118例,女性94例;年龄42~83岁,平均年...目的探析T2加权成像(T_(2)WI)联合扩散加权成像(DWI)用于直肠诊断及术前分期的效能及其相对表观扩散系数(rADC)、表观扩散系数(ADC)值与患者临床特征的相关性。方法选择疑似直肠癌患者212例,其中男性118例,女性94例;年龄42~83岁,平均年龄60.93岁;病程3个月~10年,平均病程5.64年。均行T_(2)WI联合DWI检查,以患者最终病理诊断结果为标准,计算T_(2)WI联合DWI对直肠癌的诊断效能,进行T、N分期诊断;以最终病理诊断结果为依据,计算其T、N分期诊断效能,并进行一致性检验;观察不同临床特征的患者间rADC、ADC值差异,绘制受试者工作特性(ROC)曲线,计算rADC、ADC值对直肠癌的诊断效能。结果术后病理诊断恶性172例,良性40例。T1期、T2期、T3期、T4期分别为8例、35例、31例、6例,N0期、N1期、N2期分别为37例、22例、21例。T_(2)WI联合DWI诊断直肠癌的准确度为92.45%,灵敏度为93.02%,特异度为90.00%;分期诊断中T1期、T2期、T3期、T4期诊断准确度为95.00%、93.75%、96.26%、95.00%,灵敏度为75.00%、94.12%、93.55%、71.43%,特异度为97.22%、95.65%、95.92%、97.26%。一致性检验显示T_(2)WI联合DWI与病理诊断结果的T分期诊断一致性较好(Kappa=0.863,P=0.000);N分期诊断中N0期、N1期、N2期诊断准确度分别为93.75%、90.00%、96.25%,灵敏度分别为94.59%、77.27%、95.24%,特异度分别为93.02%、94.83%、96.61%,一致性检验提示T_(2)WI联合DWI与病理诊断的N分期诊断一致性较好(Kappa=0.844,P=0.000);病变特征与rADC、ADC分析中,恶性病变rADC、ADC显著低于良性病变(0.84±0.09 vs 1.18±0.12、0.93±0.11 vs 1.39±0.11。P<0.05)。腺癌rADC、ADC显著高于黏液腺癌(0.89±0.11 vs 0.75±0.09、0.97±0.14 vs 0.83±0.11。P<0.05)。不同分化程度患者间rADC、ADC从高至低依次为高分化、中分化、低分化(rADC:0.95±0.16 vs 0.82±0.10 vs 0.72±0.08;ADC:1.05±0.17 vs 0.911±0.14 vs 0.81±0.09。P<0.05)。ADC诊断直肠癌AUC为0.987,灵敏度为92.44%,特异度为97.50%(P<0.001);rADC诊断结直肠癌AUC为0.941,灵敏度为92.44%,特异度为87.50%(P<0.001)。结论T_(2)WI联合DWI诊断直肠癌具有良好的诊断效能,且其术前T、N分期准确度高,与病理诊断一致性较好。rADC、ADC值在不同良恶性肿瘤、不同分化等级肿瘤、不同病理类型肿瘤间存显著差异,可作为良恶性及肿瘤分化程度的诊断依据。展开更多
目的探讨MRI表观弥散系数(ADC)在颈部结核性肿大淋巴结诊断治疗中的临床应用价值。方法选择52例颈部肿大淋巴结患者,其中男性25例,女性27例;年龄9~84岁,中位年龄51岁;结核性肿大淋巴结17例,炎症性肿大淋巴结19例,肿瘤性肿大淋巴结16例...目的探讨MRI表观弥散系数(ADC)在颈部结核性肿大淋巴结诊断治疗中的临床应用价值。方法选择52例颈部肿大淋巴结患者,其中男性25例,女性27例;年龄9~84岁,中位年龄51岁;结核性肿大淋巴结17例,炎症性肿大淋巴结19例,肿瘤性肿大淋巴结16例。对患者行细针穿刺病理检查并分组,采用上海联影1.5 T MRI行影像诊断。测量各组平均ADC值,并进行统计学分析。结核性肿大淋巴结患者根据3个月抗结核诊疗效果,比较其治疗前后平均ADC值变化。结果结核性肿大淋巴结组平均ADC值为(1.09±0.29)×10^(-3)mm^(2)/s,炎症性肿大淋巴结组平均ADC值为(1.27±0.39)×10^(-3)mm^(2)/s,肿瘤性肿大淋巴结组平均ADC值为(0.87±0.26)×10^(-3)mm^(2)/s。肿瘤性肿大淋巴结组与炎症性肿大淋巴结组、结核性肿大淋巴结组的ADC差异具有统计学意义(P<0.05)。炎症性肿大淋巴结组平均ADC值高于结核性肿大淋巴结组,差异无统计学意义(P>0.05)。抗结核治疗后淋巴结缩小组治疗前平均ADC值为(1.14±0.23)×10^(-3)mm^(2)/s,治疗后平均ADC值为(0.99±0.08)×10^(-3)mm^(2)/s,差异具有统计学意义(P<0.05)。淋巴结大小不变组治疗前平均ADC值(1.04±0.28)×10^(-3)mm^(2)/s,治疗后平均ADC值(0.91±0.13)×10^(-3)mm^(2)/s,差异无统计学意义(P>0.05)。淋巴结增大组治疗前平均ADC值为(1.12±0.10)×10^(-3)mm^(2)/s,治疗后平均ADC值为(1.13±0.22)×10^(-3)mm^(2)/s,差异无统计学意义(P>0.05)。结论ADC值有助于鉴别诊断颈部结核性肿大淋巴结、炎症性肿大淋巴结及肿瘤性肿大淋巴结,还可用于评估颈部淋巴结核的抗结核治疗效果,为临床诊断治疗提供参考依据。展开更多
Background Diffusion-weighted imaging has been widely used to differentiate the character of lymphadenopathy. But there are significant differences between prior studies. The aim of the study was to compare the benefi...Background Diffusion-weighted imaging has been widely used to differentiate the character of lymphadenopathy. But there are significant differences between prior studies. The aim of the study was to compare the benefit of apparent diffusion coefficient （ADC） and rADC in the differentiation of metastatic and benign lymph nodes in a rabbit model. Methods Two observers independently measured ADCs in quadriceps of every rabbit on diffusion-weighted images with different sizes of regions of interest （ROI）. The appropriate ROI for rADC was determined using the interobserver coefficient, rADC was calculated by AOClesion/AOCreference site- Receiver operating characteristics （ROC） analysis was performed to compare the diagnostic value of the ADC values and rADC values in differentiating metastatic from benign lymph nodes. Results When the ROIs included five pixels, the ICC was 0.816, indicating a good interobserver agreement. The differences of ADC and rADC values between metastatic and benign lymph nodes were both statistically significant. The area under the ROC curve was greater for the rADC than for the ADC. With the rADC criteria of 0.640, the sensitivity and specificity for differentiating metastatic from benign lymph nodes were 93% and 90%, respectively. Conclusion As a reference site, muscles reveal a good repeatability using a small ROI and the rADC may improve diagnostic accuracy for detecting metastatic nodes in animal models.展开更多
Objective： Noninvasive diffusion-weighted magnetic resonance imaging （DWI） is a well-studied MR imaging technique for quantifying water diffusion especially in tumor area. The correlation between apparent diffusion...Objective： Noninvasive diffusion-weighted magnetic resonance imaging （DWI） is a well-studied MR imaging technique for quantifying water diffusion especially in tumor area. The correlation between apparent diffusion coefficient （ADC） value and apoptosis or proliferation is not clear by now. This study aimed to investigate whether DWI-ADC value could be used as an imaging marker related with pathologic indexes of tumors. Methods： A total of 3 0 Balb/c mice with HT2 9 colorectal carcinoma were subjected to DWI and histologic analysis. The percentage of ADC changes and the apoptotic and proliferating indexes were calculated at predefined time points. Kolmogorov-Smirnov distances were considered to determine whether the percentage of ADC changes, and the apoptotic and proliferating indexes were normally distributed. An independent-samples t-test was used to analyze the difference between apoptotic and proliferating indexes in the two groups. Results： There was a statistically significant difference in proliferating index between the radiotherapy and control groups （mean proliferating index： 49.27% vs. 83.09%）, and there was a statistically significant difference in apoptotic index between the two groups （mean apoptotic index： 37.7% vs. 2.71%）. A significant positive correlation was found between the percentage of ADC changes of the viable tissue and apoptotic index. Pearson＇s correlation coefficient was 0.655 （P=0.015）. A significant negative correlation was found between the percentage of ADC changes of the viable tissue and ki-67 proliferation index. Pearson＇s correlation coefficient was 0.734 （P〈0.001）. Conclusions： Our results suggest that ADC proliferating indexes in colorectal carcinoma. value may be used in measurement of cell apoptotic and展开更多
文摘The usefulness of diffusion-weighted magnetic resonance imaging （DWI） in the evaluation of scrotal pathology has recently been reported. A standard reference of normal testicular apparent diffusion coefficient （ADC） values and their variations with age is necessary when interpreting normal testicular anatomy and pathology. We evaluated 147 normal testes using DWI, including 71 testes from 53 men aged 20-39years （group 1）, 67 testes from 42 men aged 40-69 years （group 2） and nine testes from six men older than 70years （group 3）. DWI was performed along the axial plane, using a single shot, multislice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s mm-2. The mean and standard deviation of the ADC values of normal testicular parenchyma were calculated for each age group separately. Analysis of variance （ANOVA） followed by post hoc analysis （Dunnett T3） was used for statistical purposes. The ADC values （x 10-3 mm2s-1） of normal testicular tissue were different among age groups （group 1：1.08 ± 0.13; group 2：1.15 ±0.15 and group 3：1.31± 0.22）. ANOVA revealed differences in mean ADC among age groups （F= 11.391, P〈 0.001）. Post hoc analysis showed differences between groups 1 and 2 （P= 0.008） and between groups 1 and 3 （P= 0.043）, but not between groups 2 and 3 （P= 0.197）. Our findings suggest that ADC values of normal testicular tissue increase with advancing age.
文摘Purpose: Commonly used diffusion weighted (DW) imaging such as DW spin echo (SE) type echo planar imaging (DW-SE-EPI) is known to be a snapshot-like acquisition and to have a relatively high signal-to-noise ratio. Spiral MRI sequence (SPIRAL) has characteristics similar to these of EPI, but it has rarely been used for diffusion-weighted imaging (DWI). In vivo DW-SPIRAL of the rat brain has almost never been reported. Our purpose in this study was to examine the potential of SE-type two-dimensional (2D) multi-shot spiral acquisition MRI for apparent diffusion coefficient (ADC) mapping of the rat brain in vivo. Materials and Methods: We made an SE-type DW-2D-spiral MRI sequence (DW-SPIRAL) which was prepared on a 2.0-T animal-experiment MR scanner. Comparing the phantom experimental result of DW-SPIRAL with the phantom experimental result of DW SE-type echo-planar imaging (DW-SE-EPI) and conventional DW spin echo imaging (DW-SE), we estimated the characteristics of DW-SPIRAL and assessed the clinical application of DW-SPIRAL in an animal experiment on the rat brain. Results: There was not much difference between the calculated water/glycerol phantom diffusion coefficient of DW-SPIRAL and the calculated diffusion coefficient of DW-SE. This result shows that the DW-SPIRAL sequence is appropriate for use in diffusion weighted imaging. There were fewer phantom image distortions and ghosting artifacts with DW-SPIRAL than with DW-SE-EPI, and this tendency was similar in the animal experiment on the rat brain. Conclusion: The DW-SPIRAL sequence had been successfully tested in phantom experiments and rat brain experiments. It has been demonstrated that the DW-SPIRAL sequence is capable of producing in vivo rat brain DWI.
文摘目的探析T2加权成像(T_(2)WI)联合扩散加权成像(DWI)用于直肠诊断及术前分期的效能及其相对表观扩散系数(rADC)、表观扩散系数(ADC)值与患者临床特征的相关性。方法选择疑似直肠癌患者212例,其中男性118例,女性94例;年龄42~83岁,平均年龄60.93岁;病程3个月~10年,平均病程5.64年。均行T_(2)WI联合DWI检查,以患者最终病理诊断结果为标准,计算T_(2)WI联合DWI对直肠癌的诊断效能,进行T、N分期诊断;以最终病理诊断结果为依据,计算其T、N分期诊断效能,并进行一致性检验;观察不同临床特征的患者间rADC、ADC值差异,绘制受试者工作特性(ROC)曲线,计算rADC、ADC值对直肠癌的诊断效能。结果术后病理诊断恶性172例,良性40例。T1期、T2期、T3期、T4期分别为8例、35例、31例、6例,N0期、N1期、N2期分别为37例、22例、21例。T_(2)WI联合DWI诊断直肠癌的准确度为92.45%,灵敏度为93.02%,特异度为90.00%;分期诊断中T1期、T2期、T3期、T4期诊断准确度为95.00%、93.75%、96.26%、95.00%,灵敏度为75.00%、94.12%、93.55%、71.43%,特异度为97.22%、95.65%、95.92%、97.26%。一致性检验显示T_(2)WI联合DWI与病理诊断结果的T分期诊断一致性较好(Kappa=0.863,P=0.000);N分期诊断中N0期、N1期、N2期诊断准确度分别为93.75%、90.00%、96.25%,灵敏度分别为94.59%、77.27%、95.24%,特异度分别为93.02%、94.83%、96.61%,一致性检验提示T_(2)WI联合DWI与病理诊断的N分期诊断一致性较好(Kappa=0.844,P=0.000);病变特征与rADC、ADC分析中,恶性病变rADC、ADC显著低于良性病变(0.84±0.09 vs 1.18±0.12、0.93±0.11 vs 1.39±0.11。P<0.05)。腺癌rADC、ADC显著高于黏液腺癌(0.89±0.11 vs 0.75±0.09、0.97±0.14 vs 0.83±0.11。P<0.05)。不同分化程度患者间rADC、ADC从高至低依次为高分化、中分化、低分化(rADC:0.95±0.16 vs 0.82±0.10 vs 0.72±0.08;ADC:1.05±0.17 vs 0.911±0.14 vs 0.81±0.09。P<0.05)。ADC诊断直肠癌AUC为0.987,灵敏度为92.44%,特异度为97.50%(P<0.001);rADC诊断结直肠癌AUC为0.941,灵敏度为92.44%,特异度为87.50%(P<0.001)。结论T_(2)WI联合DWI诊断直肠癌具有良好的诊断效能,且其术前T、N分期准确度高,与病理诊断一致性较好。rADC、ADC值在不同良恶性肿瘤、不同分化等级肿瘤、不同病理类型肿瘤间存显著差异,可作为良恶性及肿瘤分化程度的诊断依据。
文摘目的探讨MRI表观弥散系数(ADC)在颈部结核性肿大淋巴结诊断治疗中的临床应用价值。方法选择52例颈部肿大淋巴结患者,其中男性25例,女性27例;年龄9~84岁,中位年龄51岁;结核性肿大淋巴结17例,炎症性肿大淋巴结19例,肿瘤性肿大淋巴结16例。对患者行细针穿刺病理检查并分组,采用上海联影1.5 T MRI行影像诊断。测量各组平均ADC值,并进行统计学分析。结核性肿大淋巴结患者根据3个月抗结核诊疗效果,比较其治疗前后平均ADC值变化。结果结核性肿大淋巴结组平均ADC值为(1.09±0.29)×10^(-3)mm^(2)/s,炎症性肿大淋巴结组平均ADC值为(1.27±0.39)×10^(-3)mm^(2)/s,肿瘤性肿大淋巴结组平均ADC值为(0.87±0.26)×10^(-3)mm^(2)/s。肿瘤性肿大淋巴结组与炎症性肿大淋巴结组、结核性肿大淋巴结组的ADC差异具有统计学意义(P<0.05)。炎症性肿大淋巴结组平均ADC值高于结核性肿大淋巴结组,差异无统计学意义(P>0.05)。抗结核治疗后淋巴结缩小组治疗前平均ADC值为(1.14±0.23)×10^(-3)mm^(2)/s,治疗后平均ADC值为(0.99±0.08)×10^(-3)mm^(2)/s,差异具有统计学意义(P<0.05)。淋巴结大小不变组治疗前平均ADC值(1.04±0.28)×10^(-3)mm^(2)/s,治疗后平均ADC值(0.91±0.13)×10^(-3)mm^(2)/s,差异无统计学意义(P>0.05)。淋巴结增大组治疗前平均ADC值为(1.12±0.10)×10^(-3)mm^(2)/s,治疗后平均ADC值为(1.13±0.22)×10^(-3)mm^(2)/s,差异无统计学意义(P>0.05)。结论ADC值有助于鉴别诊断颈部结核性肿大淋巴结、炎症性肿大淋巴结及肿瘤性肿大淋巴结,还可用于评估颈部淋巴结核的抗结核治疗效果,为临床诊断治疗提供参考依据。
文摘Background Diffusion-weighted imaging has been widely used to differentiate the character of lymphadenopathy. But there are significant differences between prior studies. The aim of the study was to compare the benefit of apparent diffusion coefficient （ADC） and rADC in the differentiation of metastatic and benign lymph nodes in a rabbit model. Methods Two observers independently measured ADCs in quadriceps of every rabbit on diffusion-weighted images with different sizes of regions of interest （ROI）. The appropriate ROI for rADC was determined using the interobserver coefficient, rADC was calculated by AOClesion/AOCreference site- Receiver operating characteristics （ROC） analysis was performed to compare the diagnostic value of the ADC values and rADC values in differentiating metastatic from benign lymph nodes. Results When the ROIs included five pixels, the ICC was 0.816, indicating a good interobserver agreement. The differences of ADC and rADC values between metastatic and benign lymph nodes were both statistically significant. The area under the ROC curve was greater for the rADC than for the ADC. With the rADC criteria of 0.640, the sensitivity and specificity for differentiating metastatic from benign lymph nodes were 93% and 90%, respectively. Conclusion As a reference site, muscles reveal a good repeatability using a small ROI and the rADC may improve diagnostic accuracy for detecting metastatic nodes in animal models.
文摘Objective： Noninvasive diffusion-weighted magnetic resonance imaging （DWI） is a well-studied MR imaging technique for quantifying water diffusion especially in tumor area. The correlation between apparent diffusion coefficient （ADC） value and apoptosis or proliferation is not clear by now. This study aimed to investigate whether DWI-ADC value could be used as an imaging marker related with pathologic indexes of tumors. Methods： A total of 3 0 Balb/c mice with HT2 9 colorectal carcinoma were subjected to DWI and histologic analysis. The percentage of ADC changes and the apoptotic and proliferating indexes were calculated at predefined time points. Kolmogorov-Smirnov distances were considered to determine whether the percentage of ADC changes, and the apoptotic and proliferating indexes were normally distributed. An independent-samples t-test was used to analyze the difference between apoptotic and proliferating indexes in the two groups. Results： There was a statistically significant difference in proliferating index between the radiotherapy and control groups （mean proliferating index： 49.27% vs. 83.09%）, and there was a statistically significant difference in apoptotic index between the two groups （mean apoptotic index： 37.7% vs. 2.71%）. A significant positive correlation was found between the percentage of ADC changes of the viable tissue and apoptotic index. Pearson＇s correlation coefficient was 0.655 （P=0.015）. A significant negative correlation was found between the percentage of ADC changes of the viable tissue and ki-67 proliferation index. Pearson＇s correlation coefficient was 0.734 （P〈0.001）. Conclusions： Our results suggest that ADC proliferating indexes in colorectal carcinoma. value may be used in measurement of cell apoptotic and
