肝脏局灶性结节增生的MRI征象分析

MRI manifestation of focal nodular hyperplasia of the liver

目的:探讨肝局灶性结节增生(FNH)的典型及不典型MRI表现及与病理特点的相关性,提高FNH诊断的准确性。方法:回顾性分析33例(共40个病灶)经手术病理证实的FNH的MRI平扫和增强表现。结果:28例为单发,5例为多发病灶。40个病灶在T1WI呈等或稍低信号,在T2WI呈等或稍低信号,增强扫描动脉期31个病灶(94%)明显强化,门脉期及延迟期呈稍高或等信号;1例动脉期未见明显强化,门脉期及延迟期可见强化;1例动脉期边缘明显强化,门脉期及延迟期逐渐强化。12个病灶(30%)中心可见纤维瘢痕,11个延迟期强化,1个未见明显强化。3个病灶(8%)边缘见假包膜,延迟期可见强化。结论:MRI能较好地反映FNH内部组织学情况及血供特点,充分认识FNH的典型征象及不典型表现能帮助我们准备地做出诊断,从而避免不必要的活检及手术。

Objective：To investigate the typical and atypical MRI manifestations and pathology characteristic of hepatic focal nodular hyperplasia,so as to make a further understanding of FNH.Methods：A retrospective analysis was made on the unenhanced and dynamic enhanced MR images of 33 patients（totally 40 lesions） with pathological proved FNH.Results：Of all 33 patients,28 had solitary nodulars,5 had multiple lesions.Forty lesions were iso-or hypointensity on T1-weighted images,slight hyper-or isointensity on T2-weighted images.Thirty-one lesions（94%） present dramatic enhancement in the arterial phase,followed by hyper-or isointensity of the lesion during the portal venous phase and delayed phase.One lesion showed no enhancement in the arterial phase,and one lesion showed peripheral enhancement in the arterial phase,and with gradually enhancement on the portal venous phase and delayed phase.A central scar was noted in 12 lesions（30%）,and 11 of them showed high signal intensity on delayed phase imaging.Three lesions（8%） surrounded by a pseudocapsule,which can be seen enhancemet during delayed phase.Conclusion：MR imaging provides information concerning the soft-tissue characteristics as well as the vascularity of the lesions.Familiarity with the MR imaging findings is essential for correct diagnosis of FNH,and avoid unnecessary biopsy or even surgery.