肝紫斑病のEOB-MRI所見：2例報告

EOB-MRI findings of peliosis hepatis：a report of two cases

肝紫斑病（peliosis hepatis）は類洞壁の破壊，類洞流出路の閉塞，中心静脈の拡張に伴い類洞拡張をきたし肝内に血液貯留腔が多発するまれな病態である。画像所見が多彩であり，術前の画像診断が難しいことが多い。今回我々は，組織学的に診断された肝紫斑病の2例を経験したので，そのEOB-MRI所見を中心に提示する。

Case 1 was a woman in her 60s. Plain CT for preoperative examination of renal cell carcinoma revealed two low-density tumors in the liver. Contrast-enhanced CT showed one lesion with nodular areas of enhancement that expanded over time and another lesion that exhibited overall enhancement in early phase, indicating prolonged enhancements. On the hepatobiliary phase of EOB-MRI some high-intensity areas were observed at the margin or on the center of the tumor. Partial hepatectomy was performed in addition to laparoscopic nephrectomy. Histopathological examination revealed dilation of the sinusoids and central veins. The final diagnosis was peliosis hepatis. Case 2 was a man in his 60s. Hepatic masses were found by abdominal ultrasound incidentally. Contrast-enhanced CT showed various enhancement patterns. EOB-MRI showed faint high-intensity areas at the margin or on the center of the tumor in the hepatobiliary phase. A diagnosis of peliosis hepatis was obtained by liver biopsy. In the differential diagnoses of liver tumors with delayed enhancement such as hemangiomas, peliosis hepatis should be considered when high intensity areas were observed at the margin or the center of the tumor in the hepatobiliary phase of EOB-MRI.