肝脏妊娠的影像表现

The imaging manifestations of hepatic pregnancy

目的探讨肝脏妊娠(HP)的临床及影像特征,以提高对本病的认识及诊断能力。方法回顾性分析2例经病理证实的HP病人,分析其临床表现、病理基础及影像学特征,并进行文献复习。结果2例病人均因腹痛加重数天入院。病灶均位于肝右叶,其中1例孕囊破裂出血。CT平扫均表现为肝脏囊实性肿块,孕囊破裂病灶边缘模糊伴肝周、盆腔积血、积液。MRI平扫,孕囊T1WI低信号,T2WI高信号。CT及MRI增强扫描均显示,位于肝脏边缘、种植表浅的病灶动脉早期明显强化,静脉期开始强化程度不断下降。时间-密度或时间-信号强度曲线呈“速升速降”型。位于肝脏内部、种植深入的病灶动脉早期轻度强化,静脉期开始向心性渐进式强化,时间-信号强度曲线呈“缓升缓降”型。病理表现可见肥大伴核深染的肝细胞、滋养叶细胞及绒毛。2例病人血清人绒毛膜促性腺激素(β-HCG)水平持续升高但始终低于宫内妊娠。结论HP病人临床表现多样,腹痛最为常见。β-HCG持续升高极具特异性。影像特征表现为肝脏囊实性肿块,CT及MRI强化方式与病灶位置、深度密切相关。

Objective To explore the clinical and imaging characteristics of hepatic pregnancy(HP)to improve the understanding of the disease and the ability of diagnosis.Methods Two cases of HP confirmed by pathology were retrospectively analyzed,including their clinical presentations,pathological findings,and imaging characteristics,and literatures were reviewed.Results Both individuals were admitted to the hospital for severe abdominal pain for several days.All the lesions were located in the right lobe of the liver,gestational sac ruptured in 1 patient.Plain CT scans showed a cystic solid mass in the liver.When the gestational sac ruptured,the edge of the lesion was blurred with perihepatic and pelvic hemorrhage.MRI scans of the gestational sac showed low signal on T1WI and high signal on T2WI.Enhanced CT and MRI scans showed a superficially implanted lesion on the edge of the liver was significantly enhanced in the early arterial phase,and gradually decreased in the venous phase.The time-density or time-signal strength curve exhibited a“rapidly wash-in and wash-out”characteristic.For deeply implanted lesions inside the liver,it was slightly enhanced in the early arterial phase,and was gradually enhanced concentrically in the venous phase,and the time-signal strength curve was described as“mildly wash-in and wash-out”.Pathological findings showed hypertrophic hepatocytes with hyperchromatic nuclei,trophoblast cells,and villis.The levels of serum human chorionic gonadotropin(β-HCG)in two patients were increased over time but were lower than that of intrauterine pregnancy.Conclusion HP patient may present a variety of clinical symptoms,and abdominal discomfort is the most prevalent symptom.Persistent elevation ofβ-HCG is specific.The characteristic imaging finding is solid-cystic mass in the liver.The pattern of the enhancementon CT and MRI is related to the location and depth of the lesion.