Mn-DPDP增强MRI在肝局灶性病变中的初步应用

The Preliminary Application of Mn-DPDP Enhanced MRI in the Diagnosis of Focal Liver Lesions (a report of 14 cases)

目的:探讨Mn DPDP增强MRI在肝局灶性病变中的应用价值。方法:搜集14例患者经临床和/或病理证 实的28个肝局灶性病变,所有病例均行常规MRT1WI、T2WI平扫和Mn DPDP增强MRI,11例患者作Gd DTPA动态 增强检查,比较3者对肝局灶性病变的检出率和诊断符合率。14例患者中1例为肝血管瘤合并肝囊肿;1例FNH;12例 肝硬化并再生结节,其中合并肝细胞癌7例,合并肝囊肿4例,合并肝细胞癌和肝囊肿1例。将每例患者不同病变分别算 为1个病灶,共计28个病灶。结果:14例患者28个病灶中,12个肝硬化结节于Mn DPDP增强后呈均匀强化,以30min ～2h内强化明显,其中3个肝硬化大结节于延迟24h扫描仍有强化,于MR平扫T1WI呈高、等信号,T2WI呈低信号, Gd DTPA增强后呈缓升速降型;8个肝细胞癌灶于Mn DPDP增强后呈不均匀带状或斑片状强化,其中5个见环状假包 膜样强化,3个延迟24h扫描仍有轻度不均匀强化,病理为高中分化型肝细胞癌,于平扫T1WI呈不均匀低、等信号,T2WI 呈不均匀高、等信号,Gd DTPA增强后呈速升速降型;1个肝血管瘤及6个肝囊肿均无明显强化;1个肝局灶性结节增生 于Mn DPDP增强后早期呈轻度不均匀强化,2h后呈等信号改变。结论:Mn DPDP增强MRI对肝局灶性病变有一定鉴 别诊断价值,但对肝硬化结节。

Objective:To investigate the value of Mn-DPDP contrast enhanced imaging in the diagnosis of focal liver lesions.Methods:Fourteen patients with 28 focal liver lesions were collected,all of them were proved by diagnosis of clinic and pathology.The hepatic lesions included cirrhotic nodules (n=12),hepatocellular carcinoma (n=8),liver cyst (n=6),liver haemangioma (n=1) and focal nodular hyperplasia (n=1).MR imaging was performed with a 1.5T MR image system (GE,Signa).Conventional T 1WI,T 2WI,dynamic Gd-DTPA and Mn-DPDP contrast enhanced MRI were compared in 14 patients to determine the diagnostic accuracy of the three methods.Results:Out of 28 focal liver lesions,12 cases of cirrhotic nodules showed homogeneous enhancement in 30 minutes to 2 hours with Mn-DPDP,3 cases of them appeared slightly enhanced on delayed imaging at 24 hours.The nodules displayed high or iso-signal on T 1WI and low signal on T 2WI,and showed synchronous enhancement with normal hepatic parenchyma (type Ⅱ) on Gd-DTPA-enhanced scans.Eight cases of hepatocellular carcinoma (HCC) showed bandlike and mottling enhancement on Mn-DPDP enhanced MRI,5 cases of them showded circular enhancement,3 cases of them showed slightly heterogeneous enhancement on delayed imaging at 24 hours.One case of haemangioma and 6 cases of liver cysts had no enhancement with Mn-DPDP.One case of focal nodular hyperplasia appeared slightly heterogenous enhanced on early phase imaging and iso-intense on delayed imaging after 2 hours.Conclusion:Mn-DPDP contrast-enhanced MRI can improve the detection of focal hepatic lesions and is very helpful in differential diagnosis,but a combination of various sequences may increase the ability of differentiation.