Yuan You-Hong, Xiao En-Hua, Liu Jian-Bin, He Zhong, Jin Ke, Ma Cong, Xiang Jun, Xiao Jian-Hua, Chen Wei-Jian
Department of Radiology, Hunan Province People's Hospital, Changsha 410005, Hunan Province, China.
World J Gastroenterol. 2008 Jul 7;14(25):3997-4004. doi: 10.3748/wjg.14.3997.
To investigate dynamical and image pathological characteristics of the liver on magnetic resonance (MR) diffusion-weighted imaging (DWI) in the rabbit VX-2 tumor model.
Forty New Zealand rabbits were included in the study and VX-2 tumor piece was implanted intrahepatically. Fifteen animals received two intrahepatic implantations while 25 had one intrahepatical implantation. DWI, T1- and T2-weighted of magnetic resonance imaging (MRI) were carried out on the 7th and the 14th d after implantation and DWI was conducted, respectively on the 21st d. Ten VX-2 tumor samples were studied pathologically.
The rate of lump detected by DWI, T1WI and T2WI was 78.7%, 10.7% and 53.5% (c2=32.61, P<0.001) on the 7th d after implantation and 95.8%, 54.3% and 82.9% (c2=21.50, P<0.001) on the 14th d. The signal of most VX-2 tumors on DWI was uniform and it was equal on the map of apparent diffusion coefficient (ADC). The signal of VX tumors did not decrease on the 7th d after implantation, most of them slowly growing during the week following implantation without significant cell dying within the tumor. VX-2 tumors grew increasingly within 14 d after implantation but the signal of most VX-2 tumors on DWI or on the map of ADC was uniform or uneven and ADC of VX tumors decreased obscurely or slightly because tumor necrosis was still not obvious. On the 21st d after implantation, the signal of most VX-2 tumors on DWI or on the map of ADC was uneven because tumor necrosis was evident and ADC of VX-2 tumor necrotic areas decreased. The areas of viable cells in VX-2 tumors manifested a high signal on DWI and a low signal on the map of ADC. The areas of dead cells or necrosis in VX-2 tumors manifested low signals on DWI and low, equal or high signals on the map of ADC but they manifested high signals on DWI and on the map of ADC at the same time when the areas of necrotic tumor became liquefied or cystic. The border of tumors on DWI appeared gradually distinct and internal signals of tumor became progressively uneven.
The manifestations of viable, necrotic and liquefied or cystic areas in VX-2 tumors on DWI are typical and DWI is of significant and potential values in clinical application in both the early detection and diagnosis of liver tumors.
探讨兔VX-2肿瘤模型肝脏磁共振（MR）扩散加权成像（DWI）的动态及影像病理特征。
40只新西兰兔纳入本研究，将VX-2肿瘤块植入肝脏。15只动物进行两次肝内植入，25只进行一次肝内植入。在植入后第7天和第14天分别进行磁共振成像（MRI）的DWI、T1加权和T2加权成像，并在第21天单独进行DWI。对10个VX-2肿瘤样本进行病理研究。
植入后第7天，DWI、T1WI和T2WI检测肿块的比率分别为78.7%、10.7%和53.5%（χ2=32.61，P<0.001）；植入后第14天，分别为95.8%、54.3%和82.9%（χ2=21.50，P<0.001）。大多数VX-2肿瘤在DWI上的信号均匀，在表观扩散系数（ADC）图上信号相同。植入后第7天，VX肿瘤信号未降低，大多数在植入后一周内缓慢生长，肿瘤内无明显细胞死亡。植入后14天内VX-2肿瘤生长加快，但大多数VX-2肿瘤在DWI或ADC图上的信号均匀或不均匀，VX肿瘤的ADC值模糊降低或略有降低，因为肿瘤坏死仍不明显。植入后第21天，大多数VX-2肿瘤在DWI或ADC图上的信号不均匀，因为肿瘤坏死明显，VX-2肿瘤坏死区域的ADC值降低。VX-2肿瘤内活细胞区域在DWI上呈高信号，在ADC图上呈低信号。VX-2肿瘤内死细胞或坏死区域在DWI上呈低信号，在ADC图上呈低、等或高信号，但当肿瘤坏死区域液化或呈囊性时，它们在DWI和ADC图上同时呈高信号。肿瘤在DWI上的边界逐渐清晰，肿瘤内部信号逐渐不均匀。
VX-2肿瘤在DWI上的活、坏死及液化或囊性区域表现典型，DWI在肝脏肿瘤的早期检测和诊断的临床应用中具有重要的潜在价值。
