Gd-BOPTA增强MRI对肝脏局灶性病变的诊断价值研究

Objective: To investigate the value of Gd-BOPTA enhanced MR in the diagnosis of focal liver lesions (FLL) and the correlated pathologic basis. Materials and Methods: 17 preparative operation patients with susupected FLL were examined at 1.5T MR with Gd-BOPTA. Plain phase, arterial phase, portal venous phase, equilibrium phase and delayed hepatobiliary phase T1WI images and other conventional MR images were acquired respectively for diagnosis and analysis. The relative contrast ratio(RCR) of lesion to liver parenchyma and the signal contrast ratio(SCR) in plain phase and hepatobiliary phase were measured. All the data were analyzed according to the base of immunohistochemical and pathological results. Results: Of the 17 FLL patients, 14 cases were hepatocellular carcinoma (HCC), 2 cases were focal nodular hyperplasia (FNH) and 1 was angiomyolipoma (AML). 12 HCC and 2 FNH were correctly diagnosed according to MR images. For diagnosing HCC at Gd-BOPTA enhanced MR, the accuracy and specificity was respectively. 12 patients presented increasing SCR in all patients. HCC presented relative low signal intensity on hepatobiliary phase while some Well-differentiated HCC presented spot-like, patchy and cloud-like high signal intensity on hepatobiliary phase images., which corresponding with the presence of biliary canalicular pattern on CEA polyclonal-antibody immunostain. On the other hand, in poorly differentiated HCC, CEA immunostain was diffusely positive without biliary canalicular pattern. FNH showed remarkable high signal intensity in hepatobiliary phase and arterial phase, and CEA immunostain showed the presence of biliary canalicular pattern. AML was continuously enhanced with some necrosis area which kept un-enhanced until hepatobiliary phase in which the necrosis area began enhancing, and the reason could be concluded as retention of Gd-BOPTA in the necrosis area of the lesion. The HMB45 staining for AML was positive. Conclusion: Gd-BOPTA enhanced MR imaging is quite effective in the diagnosis of FLL for that the hepatobiliary phase images can reflect the function of hepatocytes and the presence of biliary structures of FLL, thus it will provide additional information for the characterization of FLL.