栃尾 人司¹, 岡部 純弘², 冨田 周介², 織野 彬雄², 岩崎 信広¹, 簑輪 和士¹, 曽我 登志子¹, 田村 周二¹, 森本 義人¹, 渡辺 智裕², 福永 豊和², 近藤 雅彦², 樫田 博史², 平佐 昌弘², 伊吹 康良², 工藤 正俊², 藤堂 彰男²

Hitoshi TOCHIO¹, Yoshihiro OKABE², Syusuke TOMITA², Akio ORINO², Nobuhiro IWASAKI¹, Kazushi MINOWA¹, Toshiko SOGA¹, Syuji TAMURA¹, Yoshito MORIMOTO¹, Tomohiro WATANABE², Toyokazu FUKUNAGA², Masahiko KONDO², Hiroshi KASHIDA², Masahiro HIRASA², Yasuyoshi IBUKI², Masatoshi KUDO², Akio TODO²

¹神戸市立中央市民病院臨床病理科腹部超音波検査室, ²神戸市立中央市民病院消化器センター内科

¹Division of Abdominal Ultrasound, Kobe City General Hospital, ²Department of Gastroenterology, Kobe City General Hospital

キーワード : Aberrant gastric vein, Color Doppler ultrasonography , Hyperplastic nodule , Liver cirrhosis

Sonographic examination demonstrated a roundish, well-demarcated hypoechoic nodule approximately around 2 cm in diameter in the quadrate lobe (segment IV) of the liver of a 56-year-old man with chronic hepatitis C. Abundant flow signals of constant waveform were detected within the lesion on color Doppler examination. Blood flowed into the lesion from the peripheral side of the quadrate lobe and ran in the opposite direction of normal flow in the pertinent branch of the portal vein. A dynamic helical computed tomographic study failed to depict the nodule. The lesion appeared slightly hyperintense in T 1-weighted images and moderately hypointense in T 2-weighted images. The lesion appeared as a hot spot in colloid scintigraphy with ^99mTc-phytate as well as in hepatocyte asialoglycoprotein receptor imaging with ^99mTc-GSA. X-ray digital subtraction angiography failed to demonstrate the nodule, but ultrasound angiography with intraarterial infusion of carbon dioxide microbubbles confirmed that the lesion was hypovascular. The lesion was demonstrated as a perfusion defect on computed tomography during arterial portography. Ultrasound-guided needle biopsy showed a hyperplastic lesion without malignant findings. The abnormal area in question was not well irrigated by either the artery or the portal vein; therefore, the continuous flows shown by color Doppler sonography are attributable to aberrant gastric venous drainage, which has been reported by Matsui et al. The lesion is thus considered to be a focal hyperplasia of hepatocytes that we presume to have been caused by abnormal blood inflow from the stomach.