Qi Li Ping, Zhang Xiao Peng, Tang Lei, Li Jie, Sun Ying Shi, Zhu Guang Ying
Department of Radiology, Peking University School of Oncology, Beijing Cancer Hospital & Institute, Fu cheng road 52, Hai Dian district, Beijing, 100036, China.
Eur Radiol. 2009 Feb;19(2):333-41. doi: 10.1007/s00330-008-1134-3. Epub 2008 Aug 9.
The usefulness of diffusion-weighted magnetic resonance (MR) imaging (DWI) for differentiating central lung cancer from postobstructive lobar collapse (POC) was investigated. Thirty-three cases suspected of lung cancer and POC on chest bolus computed tomography (CT) underwent thoracic MR imaging examinations. MR examinations were performed using a 1.5-T clinical scanner. Scanning sequences were T1-weighted imaging, T2-weighted imaging (T2WI) and DWI with b=0, 500 s/mm(2), four excitations and segmented breath-holding. The densities and signals of cancer and postobstructive collapsed lung were compared on bolus-enhanced CT, T2W and DW images. Statistical analyses were performed with chi-square test, paired t-test, non-parameter test and kappa statistics. Differentiation between cancer and POC was possible on bolus CT, T2W and DW images in 14, 21 and 26 patients, respectively. Eight cases that were impossible to differentiate on T2W images were distinguishable on DWI, demonstrating that DWI is complementary to T2WI. Using a combination of T2W and DW images, 88% (29/33) of cases were differentiated on MR imaging. Thus, a combination of T2W and DW imaging is superior to bolus-CT or T2WI alone. The contrast-to-noise ratio of DWI was significantly higher than that of T2WI. Agreement between two independent observers on the differential ability of lung cancer and POC was higher for DWI (kappa=0.474) than for T2WI (kappa=0.339). The degree of consolidation around the cancer was negatively correlated with the degree of artifact and degree of deformation. It is feasible to use DWI to differentiate lung cancer from POC. DWI played a role in confirming and providing complementary information to that obtained from T2WI. Our data indicate that using a combination of the two scanned sequences was the best means of distinguishing between lung cancer and POC.
研究了扩散加权磁共振（MR）成像（DWI）在鉴别中央型肺癌与阻塞性肺叶萎陷（POC）方面的效用。33例在胸部团注计算机断层扫描（CT）上疑似肺癌和POC的患者接受了胸部MR成像检查。使用1.5-T临床扫描仪进行MR检查。扫描序列包括T1加权成像、T2加权成像（T2WI）以及b = 0、500 s/mm²的DWI，4次激励并分段屏气。在团注增强CT、T2WI和DWI图像上比较癌症和阻塞性肺萎陷的密度及信号。采用卡方检验、配对t检验、非参数检验和kappa统计进行统计学分析。在团注CT、T2WI和DWI图像上分别有14例、21例和26例患者能够鉴别癌症与POC。8例在T2WI图像上无法鉴别的病例在DWI上可鉴别，表明DWI对T2WI具有互补性。结合T2WI和DWI图像，88%（29/33）的病例在MR成像上得以鉴别。因此，T2WI和DWI联合成像优于单独的团注CT或T2WI。DWI的对比噪声比显著高于T2WI。两位独立观察者在肺癌与POC鉴别能力上的一致性，DWI（kappa = 0.474）高于T2WI（kappa = 0.339）。癌症周围实变程度与伪影程度及变形程度呈负相关。使用DWI鉴别肺癌与POC是可行的。DWI在确认以及为从T2WI获得的信息提供补充方面发挥了作用。我们的数据表明，结合这两种扫描序列是区分肺癌与POC的最佳方法。
