CAJ | 학술논문

超极化气体3He或者129Xe扩散加权成像已经被证明了能够有效检测慢性阻塞性肺部疾病(COPD)中肺部微结构的改变．相比于3He，129Xe更便宜而且更容易获得，但是129Xe成像中较低的信噪比致使129Xe 的肺部表面扩散系数(ADC)的测量面临着许多困难．在该研究中，为了得到更高的图像信噪比，作者对气球模型，健康大鼠和COPD大鼠进行了单个b值(14 cm2/s)的扩散加权超极化129Xe磁共振成像(MRI)．所有的COPD模型大鼠是通过烟熏和注射内毒素(LPS)进行诱导得到的．在7 T磁共振成像仪上面获得了大鼠肺实质的超极化129Xe ADC值分布图．COPD大鼠肺实质的129Xe ADC值是0.04422±0.0029和0.04234±0.0023 cm2/s (D=0.8/1.2 ms)，远大于健康大鼠肺实质的129XeADC值0.0377±0.0023和0.0367±0.0013 cm2/s．而且COPD大鼠肺实质相关的129Xe ADC直方图也表现出了一定的展宽．这些结果说明了COPD大鼠肺泡空腔的增大能够通过129Xe在肺里面的ADC增长和相关直方图的拓宽反应出来，从而证明了单个b值的扩散加权MRI方法可以有效地对COPD大鼠进行检测．
초겁화기체3He혹자129Xe확산가권성상이경피증명료능구유효검측만성조새성폐부질병(COPD)중폐부미결구적개변．상비우3He，129Xe경편의이차경용역획득，단시129Xe성상중교저적신조비치사129Xe 적폐부표면확산계수(ADC)적측량면림착허다곤난．재해연구중，위료득도경고적도상신조비，작자대기구모형，건강대서화COPD대서진행료단개b치(14 cm2/s)적확산가권초겁화129Xe자공진성상(MRI)．소유적COPD모형대서시통과연훈화주사내독소(LPS)진행유도득도적．재7 T자공진성상의상면획득료대서폐실질적초겁화129Xe ADC치분포도．COPD대서폐실질적129Xe ADC치시0.04422±0.0029화0.04234±0.0023 cm2/s (D=0.8/1.2 ms)，원대우건강대서폐실질적129XeADC치0.0377±0.0023화0.0367±0.0013 cm2/s．이차COPD대서폐실질상관적129Xe ADC직방도야표현출료일정적전관．저사결과설명료COPD대서폐포공강적증대능구통과129Xe재폐리면적ADC증장화상관직방도적탁관반응출래，종이증명료단개b치적확산가권MRI방법가이유효지대COPD대서진행검측．
Hyperpolarized3He or129Xe diffusion MRI has been demonstrated as a promising technique for the detection of microanatomical changes in chronic obstructive pulmonary disease (COPD). Compared with 3He,129Xe is more available for the potential clinical applications. However, the measurement of129Xe apparent diffusion coefficient (ADC) possesses more challenges due to the relevant low gyromagnetic ratio and spin polarization. In this present study, a singleb value (b = 14 s/cm2) diffusion-weighted hyperpolarized129Xe MRI sequence was used to image a balloon phantom, healthy rats, and the COPD rats, respectively. All COPD rats were induced by second-hand smoke and lipopolysaccharide (LPS). The lung129XeADCmaps were obtained on a 7 T MRI scanner. The mean lung parenchymal129XeADCswere 0.044 22±0.002 9 and 0.042 34±0.002 3 cm2/s (Δ = 0.8/1.2 ms) for the COPD rats, which showed significant increasements in comparison with healthy ones (0.037 7±0.002 3 and 0.036 7±0.001 3 cm2/s). Furthermore, the correspondingADChistogram of the COPD rats exhibited a broader distribution as compared with the healthy ones. Our experiments demonstrated that the alveolar airspace enlargement in the COPD rats are able to be quantitatively evaluated by hyperpolarized xenon diffusion-weighted MRI.