肝局灶性结节增生的CT和MRI表现及误诊分析

CT and MRI findings of hepatic focal nodular hyperplasia and misdiagnosis analysis

目的探讨肝局灶性结节增生(FNH)的CT和MRI表现,提高诊断准确性。方法回顾性分析2013年9月至2019年1月温州市中心医院经病理学检查明确为肝FNH的32例患者影像学资料,行CT检查32例,MRI检查21例。结果32例共计36个病灶,单发29例,多发3例。CT平扫呈略低密度20例,等密度12例,增强扫描动脉期均见明显强化,门脉期强化不同程度减低,呈高密度26例,等密度6例;延迟期呈稍高密度5例,等密度21例,低密度6例。MRI平扫T1WI等信号13例,低信号8例;T2WI均呈稍高信号;DWI呈稍高信号15例,高信号6例;增强扫描动脉期均明显强化,门脉期呈稍高信号18例,等信号3例;延迟期呈稍高信号6例。CT检出病灶有中心瘢痕14例,增粗迂曲的供血动脉11例,假包膜5例。MRI检出病灶有中心瘢痕12例,增粗迂曲的供血动脉7例,假包膜4例。32例中2例误诊为肝癌,1例误诊为肝腺瘤。结论对于典型的肝FNH,根据CT和MRI图像一般能做出正确诊断,对于不典型肝FNH需要加强认识、注意鉴别。

Objective To explore the characteristic of CT and MRI imaging in hepatic focal nodular hyperplasia(FNH)and further to improve the diagnostic accuracy.Methods The imaging data of 32 cases with FNH confirmed by pathology were analyzed retrospectively between Sep.2013 to Jan.2019,32 cases underwent CT and 21 cases hepatic undenwent MRI.Results A total of 36 lesions were detected in the 32 patients,among them 29 patients had 1 lesion each,and the remaining 3 patients had multiple lesions.Pre-contrast CT scan showed slightly lower density in 20 cases,and equal density in 12 cases.Enhanced scan showed obvious enhancement in the arterial phase.The enhancement in the portal phase decreased in varying degrees,showing high density in 26 cases,and isodensity in 6 cases.For delayed phase,slightly high density was seen in 5 cases,isodensity in 21 cases,and low density in 6 cases.Pre-contrast MRI scan showed 13 lesions of isointense,and 8 lesions of hypointense on T1WI.All the 21 lesions showed slight hyperintense on T2WI.15 of 21 lesions showed slight hyperintense,and the other 6 lesions showed hyperintense on DWI.On the arterial phase of MRI scanning,all lesions were markedly enhanced.On the portal phase scanning,18 lesions showed slight hyperintense,and the other 3 lesions showed isointense.On delayed phase scanning,6 lesions showed slight hyperintense.On CT scanning,central scar was found in 14 lesions,tortuous and dilated arteries at the peripheral area in 11 lesions,and pseudocapsule sign in 5 lesions.On MRI scanning,central scar was seen in 12 lesions,tortuous and dilated arteries at the peripheral area in 7 lesions,and pseudocapsule sign in 4 lesions.Of the 32 cases,2 were misdiagnosed as hepatocellular carcinoma and 1 as hepatic adenoma.Conclusion For typical hepatic FNH,the correct diagnosis can be made according to CT and MRI images.For atypical hepatic FNH,we need to strengthen understanding and pay attention to identification.