【摘要】 目的探讨 MRI 对各型肝脏孤立性坏死结节（SNN）的诊断价值。方法分析经手术病理证实的 SNN 9例,并结合文献资料探讨其分型、各型的 MR 表现及其病理基础。结果（1）单纯凝固性坏死型（5例）,MRI 的 T₁WI 及 T₂WI 上分别表现为低信号或低-等信号,增强扫描病灶内部无强化,周围包膜呈轻-中度强化。病理显示为单纯凝固性坏死,外围有薄层纤维包膜。（2）伴液化性坏死型（1例）,T₁WI 上表现为低信号,较大病灶内可见点片状更低信号;T₂WI 上病灶呈低-等信号,其内可见点片状高信号;增强后病灶内部无强化,周围包膜呈轻-中度强化。病理上以凝固性坏死为主,中心可见裂隙状液化性坏死,外围有薄层纤维包膜。（3）多结节融合型（3例）,T₁WI 为低信号,其内可见低-等信号分隔;T₂WI 病灶以低信号为主,其内可见等或略高信号分隔;增强扫描病灶内部无强化,其内分隔及周围包膜呈轻-中度强化。病理呈多个坏死结节融合,病灶以凝固性坏死为主,部分较大结节内可见小片状液化性坏死,结节间可见纤维分隔及外围薄层纤维包膜。结论 MRI 能很好反映 SNN 的分型及各型的病理特征。更多还原

【Abstract】 Objective To analyze the classification,MR manifestations,and the pathological basis of solitary necrotic nodule of the liver（SNN）in order to evaluate MRI as a diagnosing tool Methods The MR appearances of 9 cases with pathologically proved SNN were analyzed and correlated with the classification and pathological appearances.Relevant literature was reviewed.Results（1）Simple coagulative necrosis type（5 cases）:The signal of lesions was hypo-intense or iso-intense on both T₁-and T₂- weighted images.After Gd-DTPA administration,the internal part of the lesions showed no enhancement,while the thin capsule of the lesions demonstrated mild or moderate delayed enhancement. These lesions,proved by pathology,were composed of central coagulative necrotic core and a peripheral hyaline fibrosis capsule.（2）Coagulative necrosis aceompanied by liquefactive necrosis type（1 case）:On T₁-weighted images,the signal of hypo-intensity was found within these lesions and even lower signal intensity was found in the central area of larger lesions.On T₂-weighted images,the lesions had a bright core and a peripheral hypointensive or isointensive area.After Gd-DTPA administration,the internal part of the lesions showed no enhancement,while the thin capsule of the lesions demonstrated mild or moderate delayed enhancement.These lesions had a central coagulative necrosis core interleaved by slit- like liquefactive necrosis foci,and peripherally a thin capsule of hyaline fibrosis proved by pathology.（3）Multi-nodular fusion type,（3cases）:On T₁-weighted images,the lesions were of hypointensive or isointensive signal and had multiple septa of isointensive signal.On T₂-weighted images,the lesions were of hypointensive or isointensive signal and had multiple septa of hyperintensive or isointensive signal.After Gd-DTPA administration,No enhancement was found except mild or moderate delayed enhancement found in the thin capsule and septa.These lesions were composed of central coagulative necrosis area and a peripheral hyaline fibrosis capsule with multiple internal septa proved by pathology.Conclusion MRI apperances can reflect the classification and pathological features of solitary necrotic nodule of the liver.更多还原