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
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 S...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.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
Aim: To investigate the diagnostic efficiency of apparent diffusion coefficient value (ADC) in differentiating benign from malignant breast lesions at 3.0 T diffusion-weighted imaging with different pair of b value. M...Aim: To investigate the diagnostic efficiency of apparent diffusion coefficient value (ADC) in differentiating benign from malignant breast lesions at 3.0 T diffusion-weighted imaging with different pair of b value. Methods: Total 110 patients with 107 lesions (44 benign and 63 malignant) were selected for our study with five different b-values 0, 400, 800, 1200 and 1600 s/mm<sup>2</sup>. ADC values were calculated using different pairs of b values. The cut-off ADC values and diagnostic efficiency were evaluated by receiver operating characteristic analysis. Comparison of Mean ADC value for breast lesions was determined by using independent sample t test. ROC curves were used for diagnostic efficiency of ADC using different pairs of b values. Results: With increase of b value, mean ADC value decreases. The mean ADC values for benign were 1.73 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 400, 1.57 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 800, 1.43 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1200 and 1.30 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1600 s/mm<sup>2</sup>. The mean ADC values for the malignant breast lesion were 1.21 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 400, 1.06 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 800, 0.94 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1200 and 0.86 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1600 s/mm<sup>2</sup>. ADC diagnostic efficiency for benign and malignant lesion for all the pair of b value combination was significant (p > 0.05). The sensitivity, specificity, PPV, NPV and accuracy were 80.95%, 90.9%, 92.72%, 76.92%, 85.04% for b 0 and 400;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 800;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 1200;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 1600 s/mm<sup>2</sup> respectively. Conclusion: DWI is effective in differentiating benign and malignant breast lesion at 3.0 Tesla using ADC with higher b value combination.展开更多
目的探讨DWI表观扩散系数(apparent diffusion coefficient,ADC)值对鉴别肺部良、恶性病变的价值及b值优化。方法对82例肺部结节或肿块行常规MRI和DWI检查,分别测量b值为300、500、800s/mm2时的病变ADC值。比较同一b值下良、恶性病变AD...目的探讨DWI表观扩散系数(apparent diffusion coefficient,ADC)值对鉴别肺部良、恶性病变的价值及b值优化。方法对82例肺部结节或肿块行常规MRI和DWI检查,分别测量b值为300、500、800s/mm2时的病变ADC值。比较同一b值下良、恶性病变ADC值的差异。根据受试者工作特征曲线(r e c e i v e o p e r a t i n g characteristic curve,ROC)评价不同b值下ADC值鉴别肺部良恶性病变的诊断效能。结果 82个病例中恶性病变54例,良性病变28例。不同b值下恶性病变的平均AD均值均明显小于良性病变平均ADC值,差异均有统计学意义(P均<0.05)。b值取300、500、800s/mm2,AUC分别为0.806,0.838,0.826,均有诊断意义(AUC>0.5);其中b=500s/mm2时ADC值诊断效能最高,ADC阈值为1.492×10-3mm2/s,其敏感度、特异度、准确度分别为88.9%、78.6%、85.92%。结论 ADC值有助于鉴别肺部良恶病变,b值取500s/mm2时诊断效能较高。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.
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
文摘Aim: To investigate the diagnostic efficiency of apparent diffusion coefficient value (ADC) in differentiating benign from malignant breast lesions at 3.0 T diffusion-weighted imaging with different pair of b value. Methods: Total 110 patients with 107 lesions (44 benign and 63 malignant) were selected for our study with five different b-values 0, 400, 800, 1200 and 1600 s/mm<sup>2</sup>. ADC values were calculated using different pairs of b values. The cut-off ADC values and diagnostic efficiency were evaluated by receiver operating characteristic analysis. Comparison of Mean ADC value for breast lesions was determined by using independent sample t test. ROC curves were used for diagnostic efficiency of ADC using different pairs of b values. Results: With increase of b value, mean ADC value decreases. The mean ADC values for benign were 1.73 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 400, 1.57 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 800, 1.43 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1200 and 1.30 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1600 s/mm<sup>2</sup>. The mean ADC values for the malignant breast lesion were 1.21 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 400, 1.06 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 800, 0.94 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1200 and 0.86 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1600 s/mm<sup>2</sup>. ADC diagnostic efficiency for benign and malignant lesion for all the pair of b value combination was significant (p > 0.05). The sensitivity, specificity, PPV, NPV and accuracy were 80.95%, 90.9%, 92.72%, 76.92%, 85.04% for b 0 and 400;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 800;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 1200;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 1600 s/mm<sup>2</sup> respectively. Conclusion: DWI is effective in differentiating benign and malignant breast lesion at 3.0 Tesla using ADC with higher b value combination.
文摘目的探讨乳腺动态增强磁共振成像(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)、时间-信号强度曲线(time-signal intensity curve,TIC)及表观弥散系数(apparent diffusion coefficient,ADC)预测乳腺癌激素受体(hormone receptor,HR)表达状态的价值,评估MRI特征与激素受体状态之间的相关性及预测价值。材料与方法回顾性分析2019年11月至2025年3月206例经病理证实为浸润性乳腺癌患者的MRI表现,分析DCE-MRI中形态学特征、TIC与ADC值在不同HR表达状态(HR+/HR-)乳腺癌之间的差异,对差异有统计学意义的MRI表现进行单因素及多因素联合的logistic回归分析,并绘制ROC曲线,评估MRI特征预测乳腺癌激素受体表达状态的效能。结果HR+组与HR-组的形态学特征(包括肿瘤最大径、边缘、毛刺征、强化方式)、TIC与ADC的差异均具有统计学意义(P<0.05),HR+更容易表现为最大径≤2 cm、边缘不清晰、有毛刺、不均匀强化和TIC为Ⅲ型曲线,且平均ADC值低于HR-。其中MRI形态学特征、ADC值可以预测激素受体阳性或阴性乳腺癌,曲线下面积(area under the curve,AUC)分别为0.806(95%CI:0.747~0.864)、0.669(95%CI:0.593~0.744),敏感度分别为74.1%、75.3%、特异度分别为74.4%、51.2%,而将二者联合预测HR表达状态的AUC为0.837(95%CI:0.784~0.890),敏感度、特异度分别为84.0%、65.6%,其中MRI形态学特征联合ADC值的鉴别价值最高。结论MRI形态学特征、ADC值联合模型对于乳腺癌激素受体表达状态具有较好的预测价值,从而为临床治疗方案的制订和调整提供依据。
文摘目的探讨DWI表观扩散系数(apparent diffusion coefficient,ADC)值对鉴别肺部良、恶性病变的价值及b值优化。方法对82例肺部结节或肿块行常规MRI和DWI检查,分别测量b值为300、500、800s/mm2时的病变ADC值。比较同一b值下良、恶性病变ADC值的差异。根据受试者工作特征曲线(r e c e i v e o p e r a t i n g characteristic curve,ROC)评价不同b值下ADC值鉴别肺部良恶性病变的诊断效能。结果 82个病例中恶性病变54例,良性病变28例。不同b值下恶性病变的平均AD均值均明显小于良性病变平均ADC值,差异均有统计学意义(P均<0.05)。b值取300、500、800s/mm2,AUC分别为0.806,0.838,0.826,均有诊断意义(AUC>0.5);其中b=500s/mm2时ADC值诊断效能最高,ADC阈值为1.492×10-3mm2/s,其敏感度、特异度、准确度分别为88.9%、78.6%、85.92%。结论 ADC值有助于鉴别肺部良恶病变,b值取500s/mm2时诊断效能较高。
