肝脏动脉期一过性强化灶ppt课件

肝内动脉期一过性强化灶,工作中关注点：没有明显原因的肝内动脉期一过性强化灶。,男性，56岁楔形动脉期一过性强化灶肝动脉期CT楔形一过性强化灶，同期的MRI/CT和B超，没有发现局部病灶：56-year-old man with sectorial fan-shaped transient hepatic intensity difference associated with cholangiocellular carcinoma. Axial iodinated contrast-enhanced arterial phase helical CT image shows sectorial arterial phenomenon (arrowheads) apparently not associated with focal lesion.,三月后，梯度回波T1动脉期楔形的尖部可见小的低信号病灶，胆管细胞癌，门脉分支浸润所致门脉低灌注Axial gradient-echo T1-weighted gadolinium-enhanced arterial phase MR image (TR/TE, 216/1.5) obtained 3 months afterAshows small hypointense focal lesion (arrow) at apex of fan-shaped arterial phenomenon, causing portal branch infiltration and subsequent portal hypoperfusion.,Transient Hepatic Intensity Differences: Part 1, Those Associated with Focal LesionsStefano Colagrande1,Nicoletta Centi1,Roberta Galdiero2andAlfonso Ragozzino2 Affiliations:1Department of Clinical Physiopathology, Section of Radiodiagnostics, University of Florence, Viale Morgagni 85, Florence 50134, Italy.2Section of Radiodiagnostics, Ospedale SM Grazie Pozzuoli, Naples, Italy.Citation:American Journal of Roentgenology. 2007;188: 154-159.图片摘自上文，,工作中一点体会（不是十分的严谨）上腹部CT增强扫描中：动脉期发现肝脏楔形或三角形一过性强化灶（次要矛盾），如果没有发现伴随的局部病灶（主要矛盾），别忘了建议进行MRI平扫+增强扫描。如果B超和MRI检查没有发现病灶，并且其他资料能够作为病因解释的，是否可以建议：三月后进行MRI平扫+增强扫描？以期发现潜在的转移或原发的恶性病变。,参考文献,参考文献,定义：肝脏一过性灌注异常，THPD。又称为一过性肝脏密度差异，或一过性肝实质强化，是一种局灶性、节段性或弥漫性的肝脏血流动力学异常，绝大部分为病理性改变。大多数的THPD不会引起临床症状。,肝脏灌注异常的历史渊薮sou 1981年，Inamoto发现了非肿瘤性肝段低密度区，并认为形成原因可能为门静脉血流减少所致；1982年Itai报道了CT增强扫描时动脉期肝段一过性异常强化现象，并称之为一过性肝密度差异，并于1988年报道了MR检查时出现的肝段异常信号，表现为长T1长T2信号影，并发现了部分病例相应肝区域超声检查为斜形低回声区，肝动脉造影有明确肝段染色 1984年，Matsui为肝脏肿瘤患者行DSA检查时发现，肿瘤区以外的正常肝包膜下肝组织中出现染色缺失区，发现肝段染色区就是CT增强动脉期异常强化区；1996年国内学者周康荣明确提出了肝脏一过性异常灌注1；1997年Gryspeerdt等首次提出了肝脏灌注异常（hepatic perfusion disorders）的概念，他根据肝脏在多排螺旋CT增强扫描时出现的肝脏密度差异，进行了系统的研究和综述，并提出与HPD形成相关的疾病，较Itai及Matsui提出观点更全面、更具体，更能全面反映其影像检查所见的本质特征；2006年文星回顾性分析了128例肝一过性异常灌注的CT表现。目前大多数学者主张使用肝脏灌注异常来进行命名。,THPD的影像学表现-CT表现高密度灌注异常CT表现：增强扫描时表现为动脉期一过性肝实质楔形、三角形、类圆形以及不规则高密度影，密度均匀，边缘清晰，与周边肝组织之间有清楚的窄移行带，脉管系统无移位，在高密度灌注异常影中可见血管影，门静脉期恢复等密度，可单发或多发。异常高灌注多出现在肝包膜下以及肝浅表部、肝病变组织周围，也可累及肝段、亚段以及肝叶。低密度灌注异常CT表现：增强扫描时表现为动脉期一过性肝实质内楔形、三角形低密度影，密度均匀，边界锐利或与周围组织之间无明确边界，门静脉期恢复等密度；异常低灌注多出现于镰状韧带、静脉韧带、胆囊窝附近以及肝浅表部位等。肝脏灌注异常CT平扫表现：CT平扫大多数表现为等密度，少数表现为楔形或三角形低密度区。,视角：形态（与具体的病因相关）,肝叶、肝段型：异常静脉引流，楔形或者三角形：肝恶性病变，血管瘤；活检弥漫型：布-加氏综合征；肝硬化结节型？多形态型？胆管炎，胆道梗阻，布-加,THPD产生的原因和及机理,肝脏的血供是基础：门静脉7580% ，肝动脉20%25% 动-门（肝）静脉异常沟通；盗血虹吸外压；异常静脉引流；（异常动脉供血？）,肝脏异常灌注的病因,创伤及各种经过肝实质的介入性操作；肿瘤：良性肿瘤：血管瘤，炎性假瘤，FNH,嗜酸性肉芽肿； 恶性肿瘤：肝癌、胆管细胞癌、转移癌（富血供？）炎症：胆管炎，肝脓肿，门静脉、肝静脉梗阻（癌栓、布-加），主要胆道梗阻；先天性的：动静（门）脉畸形，异常静脉引流肝脏内血管受挤压或阻塞 ：肝周肿瘤、包膜下积液、巨脾、大量胸腔积液及外伤致肋骨压迫等,创伤及各种介入性操作：肝实质的挫裂及肝内血管的断裂；各种介入性操作：包括经皮肝穿刺活检术、取石术、胆道引流术、肿瘤的物理消融术等；各种损伤的共同机制是-导致肝动脉与门静脉之间的直接交通，引起动脉-门静脉分流，导致肝动脉血流进入门静脉系统，而出现肝动脉血流的重新分配，它是产生肝脏异常高灌注的主要原因。,创伤：活检,经皮肝穿刺活检一月后三角：扇形动脉期一过性强化灶箭头：肝动脉-门静脉瘘42-year-old woman with sectorial transient hepatic intensity differences in right hepatic lobe caused by posttraumatic arterioportal shunt. Axial gradient-echo T1-weighted gadolinium-enhanced arterial phase MR image (TR/TE, 146/2) shows wedge-shaped arterial phenomenon (arrowheads) caused by arterioportal shunt (arrow) due to percutaneous hepatic biopsy performed 1 month earlier.,肿瘤：包括肝脏良性肿瘤与恶性肿瘤。肝脏良性肿瘤主要有血管瘤、炎性假瘤及肝局灶性结节增生(focal nodular hyperplasia,FNH)；肝脏恶性肿瘤主要是指肝细胞癌、胆管细胞癌、肝肉瘤及各种富血供转移瘤等。恶性病变侵蚀血管,造成动-静脉瘘；当肿瘤较大伴有门静脉及肝静脉瘤栓形成时,可通过肝窦、脉管等多种途径引起动脉-门静脉、肝动静脉分流。肝脏富血供肿瘤的“盗血”作用,也是产生肝脏病理性灌注异常常见原因。,65岁男性，肝细胞肝癌；肝硬化。癌灶和子灶。门静脉分支癌栓（白色箭头）导致楔形动脉期一过性强化灶，癌栓并在T2图像上得到证实。,65岁男性患者，肝细胞肝癌；肝硬化。癌灶和子灶。门静脉分支癌栓（白色箭头）导致楔形动脉期一过性强化灶，并在T2图像上得到证实。65-year-old man with liver cirrhosis and hepatocellular carcinoma causing sectorial wedge-shaped transient hepatic intensity difference induced by portal thrombosis secondary to tumor. Axial T2-weighted MR image (12,000/82) confirms portal thrombosis (arrowhead) and shows slight signal intensity changes in triangular area of arterial phenomenon due to small increase in amount of free water.,59岁男性患者，结肠癌肝转移门静脉受压；不是原发的肝动脉血流增加。肿瘤外侧的楔形动脉期一过性强化灶；Fig. 10C59-year-old man with large hepatic intraparenchymal metastasis from colon carcinoma and correlated sectorial fan-shaped transient hepatic intensity difference. Axial gradient-echo fat-suppressed T1-weighted unenhanced (146/2) (B) and axial gradient-echo fat-suppressed T1-weighted gadolinium-enhanced arterial phase (146/2) (C) MR images show wide fan-shaped arterial phenomenon with straight border (arrowhead,C) due to hypointense neoplastic lesion at its apex (arrow), causing portal compression. Note how segment III is also slightly enhanced. Although this transient hepatic intensity difference could look like lobar type because of distribution, this arterial phenomenon is undoubtedly sectorial because lesion, being hypodense and hypoenhancing, causes portal compression and not a primary increase in arterial flow.,50岁男性患者肝包膜下血管瘤楔形动脉期一过性强化灶B超见楔形区域低回声，彩色多普勒可见肝动脉-门静脉分流6B50-year-old man with small round hemangioma beneath Glissons capsule in right hepatic lobe and intralesional arterioportal shunt producing sectorial wedge-shaped arterial phenomenon. Axial T2-weighted (TR/TE, 830/80) (A) and axial gradient-echo unenhanced T1-weighted (216/1.5) (B) MR images show right hepatic lobe nodule (arrow) that is strongly hyperintense inAand hypointense inB.,肝包膜下的血管瘤楔形动脉期一过性强化灶,B超见楔形区域低回声，彩色多普勒可见病灶内肝动脉-门静脉分流,34岁女性患者FNH虹吸-盗血1A34-year-old woman with fibronodular hyperplasia in left hepatic lobe determining homolateral lobar transient hepatic intensity difference (lobar siphoning effect). Axial T2-weighted MR image (TR/TE, 830/80) shows slightly hyperintense nodule (arrow) in left hepatic lobe.,34岁女性患者FNH虹吸-盗血病灶周围的强化灶肝段型实质强化 parenchyma in segments II-IV.,34岁女性患者FNH虹吸-盗血病灶周围的强化灶肝段型实质强化 parenchyma in segments II-IV.门静脉期病灶周围未见强化灶,血管瘤虹吸-盗血病灶周围的强化灶肝段性的强化灶segment II.,胆管炎多形性炎性刺激动脉扩张、盗血,T2见扩张的单管，肝周渗出（图1）（图2）管周动脉强化供血，一过性强化（图3）分布在扩张的胆管旁，假球状强化灶，容易误诊为局部病灶。5C57-year-old woman with cholangitis and nonsectorial transient hepatic intensity differences in hepatic dome. Axial gradient-echo T1-weighted gadolinium-enhanced arterial phase MR