探讨土三七致肝窦阻塞综合征(HSOS)的CT及MRI的表现与特征。

收集经临床或肝穿刺活检病理证实的服用土三七致HSOS的初诊患者20例。其中男性19例，女性1例；其中12例经肝组织活检证实，8例经临床表现、土三七药用史及辅助检查综合诊断。20例患者均有外伤、脑卒中后服用土三七病史，服药后10天~6个月出现临床症状。回顾性分析患者的临床资料、腹部CT及MR主要表现。

20例患者中有14例患者行CT检查，11例患者行MRI检查。CT平扫显示肝实质密度不均，增强扫描门脉期、延迟期肝实质灌注不均，呈地图样、花斑样强化；MRI平扫较CT平扫可以更清楚显示肝实质密度情况，沿肝静脉三大分支走行处的肝实质信号较其余部分肝实质信号稍高并更均匀，三支肝静脉纤细或显示不清，肝段下腔静脉静脉纤细或扁平，但下腔静脉及肝静脉仍然通畅；此外，CT与MRI均能显示门脉周围水肿，门脉高压症表现。

土三七致HSOS的CT及MRI表现具有一定的特征；CT、MRI检查在复查及评价临床疗效中具有重要作用；MRI检查可较好评价肝实质损伤程度及肝内静脉通畅情况，CT图像重建可清楚显示下腔静脉及肝内主要血管，二者在诊断及鉴别诊断中具有重要作用，结合患者土三七药用史及病理检查，有助于HSOS诊断。

to explore the imaging manifestations of sinusoidal obstruction syndrome (HSOS) caused by Gynura segetum.

A total of 20 cases of HSOS caused by consuming Gynura segetum were confirmed by clinical diagnosis and liver biospy. Including them there are 19 males and 1 female; 12cases confirmed by the liver biospy, 8 cases with clinical manifestations, medical history and lab examinations comprehensive diagnosis. All patients had trauma, stroke history, after taking 10 days to 6 months of clinical symtoms. The clinical data, CT and MR imagings had be analyzed in this article.

A total of 14 cases underwent CT scan and 11 cases accepted MRI examination. Unenhanced CT features are heterogenous hypodensity of liver parenchyma, the portal venous and delayed phases of hepatic enhancement performed uneven and poorly perfusion. The MRI examination can show the liver parenchyma more clearly than the CT scan, the liver parenchyma along the three main hepatic veins appears higher and more even signal than the rest part of the liver. The three main hepatic veins seemed tiny, light or absence, the inferior vena cava became compressed but unobstructed. The periportal edema and portal hypertension also represented.

The HSOS caused by Gynura segetum have a certain degree of typical imaging findings. The CT and MRI examination have a important role in the review and evaluation of clinical efficacy. The MRI examination can better assess the liver parenchymal damage and intrahepatic venous situation, the imaging postprocessing technique of CT can clearly show the inferior vena cava and intrahepatic vessels. These two examination have important effect in diagnosis and differential diagnosis of HSOS, combing with Gynura segetum consuming history and pathological examination, can help to suggest the diagnosis of HSOS.