BACKGROUND： Because magnetic resonance diffusion-weighted imaging is sensitive to water molecule movement, it has particular advantages for early diagnosis of cerebral infarction. However, the relationship between ap...BACKGROUND： Because magnetic resonance diffusion-weighted imaging is sensitive to water molecule movement, it has particular advantages for early diagnosis of cerebral infarction. However, the relationship between apparent diffusion coefficient changes with ischemia time, particularly relative apparent diffusion coefficient and tissue pathological changes remains controversial. OBJECTIVE： To explore the correlation between apparent diffusion coefficient changes and pathologic changes in hyperacute cerebral infarction. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment of neuroimaging. The study was performed at the Laboratory of Radiology Department, Longgang Central Hospital of Shenzhen from October 2007 to October 2008. MATERIALS： Magnetic resonance scanner was purchased from Philips Medical Systems, Best, the Netherlands. METHODS： A total of 42 healthy, adult, New Zealand rabbits were randomly assigned into sham-operation, ischemia 0.5-, 1-, 2-, 3-, 4-, and 6-hour groups, with six animals in each group. Local cerebral ischemia model was established by right middle cerebral artery occlusion, and cranial MRI scanning and pathologic observation were performed, respectively, at 0.5, 1,2, 3, 4, and 6 hours following ischemia. The middle cerebral artery of sham-operation group was only exposed, but not occluded. Images at the above-mentioned time points were also collected. MAIN OUTCOME MEASURES： Apparent diffusion coefficient and relative apparent diffusion coefficient values of abnormal signal on diffusion-weighted imaging were calculated and compared with pathological changes in the ischemic region. RESULTS： No abnormal diffusion-weighted imaging signals or pathological changes were observed in the sham-operation group. Abnormal signal intensity on diffusion-weighted imaging was first observed in the 0.5-hour group. Apparent diffusion coefficient and relative apparent diffusion coefficient values decreased in all middle cerebral artery occlusion rabbits and reached lowest levels a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为展开更多
基金Supported by:the Key Program of Shenzhen Health Bureau,No.200605
文摘BACKGROUND： Because magnetic resonance diffusion-weighted imaging is sensitive to water molecule movement, it has particular advantages for early diagnosis of cerebral infarction. However, the relationship between apparent diffusion coefficient changes with ischemia time, particularly relative apparent diffusion coefficient and tissue pathological changes remains controversial. OBJECTIVE： To explore the correlation between apparent diffusion coefficient changes and pathologic changes in hyperacute cerebral infarction. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment of neuroimaging. The study was performed at the Laboratory of Radiology Department, Longgang Central Hospital of Shenzhen from October 2007 to October 2008. MATERIALS： Magnetic resonance scanner was purchased from Philips Medical Systems, Best, the Netherlands. METHODS： A total of 42 healthy, adult, New Zealand rabbits were randomly assigned into sham-operation, ischemia 0.5-, 1-, 2-, 3-, 4-, and 6-hour groups, with six animals in each group. Local cerebral ischemia model was established by right middle cerebral artery occlusion, and cranial MRI scanning and pathologic observation were performed, respectively, at 0.5, 1,2, 3, 4, and 6 hours following ischemia. The middle cerebral artery of sham-operation group was only exposed, but not occluded. Images at the above-mentioned time points were also collected. MAIN OUTCOME MEASURES： Apparent diffusion coefficient and relative apparent diffusion coefficient values of abnormal signal on diffusion-weighted imaging were calculated and compared with pathological changes in the ischemic region. RESULTS： No abnormal diffusion-weighted imaging signals or pathological changes were observed in the sham-operation group. Abnormal signal intensity on diffusion-weighted imaging was first observed in the 0.5-hour group. Apparent diffusion coefficient and relative apparent diffusion coefficient values decreased in all middle cerebral artery occlusion rabbits and reached lowest levels a
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
