Membranous obstruction of the inferior vena cava with Budd-Chiari syndrome: MR imaging findings.

Membranous obstruction of the inferior vena cava (IVC) is a curable cause of a primary type of Budd-Chiari syndrome. Magnetic resonance (MR) imaging and vena cavography were performed on nine patients with membranous obstruction of the IVC. The MR findings were retrospectively analyzed and compared with computed tomographic findings in seven patients. The morphologic features of membranous obstruction of the IVC on spin-echo MR images were a curvilinear soft-tissue membrane (five cases) or an obliterated lumen of a hepatic segment of the IVC (four cases) in transverse or sagittal views. The lumen below the obstruction revealed flow-related signal (seven cases), intraluminal thrombus (one case), and thrombotic occlusion (one case). The hepatic veins were narrow and disoriented without connection to the hepatic segment of the IVC just below the diaphragm. On T2-weighted images, inhomogeneity with high signal intensity was shown more prominently in the hepatic parenchyma in Simson type II or III membranous obstruction. Other findings were hepatosplenomegaly, enlarged caudate lobe, cirrhotic liver, associated hepatoma, and presence of various collaterals.     

Preoperative CT and MR imaging of inferior vena cava leiomyosarcoma

We investigated the radiological findings of five patients with primary leiomyosarcoma of the inferior vena cava (IVC) comparing cavography, computed tomography (CT), and magnetic resonance imaging (MRI). The radiographic presentation ranged from an intraluminal lesion with obstruction of the IVC to a tumor mass extending from the media musculature into the surrounding perivascular tissue with only slight protrusion into the lumen. The lesions were associated with late or few symptoms. Pathognomonic radiological findings could not be established. In cases with an extraluminal growth a lobulated, well-defined, encapsulated tumor with an inhomogeneous contrast uptake is characteristic in CT studies. Additional information was provided by MRI. Leiomyosarcomas with extraluminal involvement showed homogeneous intermediate signal intensity (SI) on Tl-, and mixed intermediate/high SI on T2-weighted images. In cases with predominantly intraluminal growth, both CT and MRI demonstrated the IVC to be dilatated and allowed to differentiate between tumor extent and obliterating thrombosis. Modern imaging modalities allow an early and accurate pre-operative diagnosis resulting in a higher rate of surgical resection and improvement of survival.     

Retrieving the Amplatz retrievable vena cava filter

The new Amplatz retrievable filter was placed 15 times into the inferior vena cava (IVC) of 7 dogs. Retrieval of the filter was attempted in 11 cases after 1 week and in 3 cases after 2 weeks. The retrieval was successful and without complication in all 14 cases. The 15th placement resulted in thrombotic occlusion of the IVC, and no retrieval was attempted.     

Filter-related,thrombotic occlusion of the inferior vena cava treated with a Gianturco stent

The authors report a case of complete thrombotic occlusion of the inferior vena cava (IVC), which occurred 4 weeks after placement of an IVC filter (TrapEase; Cordis, Miami FL). Initial treatment with suction thrombectomy and thrombolysis was ineffective. Percutaneous removal of the filter was unsuccessful because of the long period of implantation. TrapEase filters (Cordis) are easily collapsible because of their symmetric design and composition (nitinol). An expandable metallic Gianturco Z stent (Cook, Bloomington, IN) was used to exclude the filter from the vessel lumen. In cases of persistent filter-related, thrombotic occlusion of the IVC, in which initial treatment has failed, the use of a Gianturco stent (Cook) to exclude the filter from the vessel lumen is a viable treatment option if the filter has a collapsible design.     

Acute thrombosis of the inferior vena cava and hepatic veins in patients with Budd-Chiari syndrome: CT demonstration

We reviewed the CT findings in 17 patients with angiographically proved Budd-Chiari syndrome to determine the ability of CT to show acute thrombosis of the inferior vena cava (IVC) and hepatic veins. In eight patients with membranes (web or band) in the IVC, no thrombus was detected with CT or angiography. In the other nine patients, thrombi in the IVC and/or hepatic veins were seen as intraluminal filling defects that did not change in appearance on precontrast and postcontrast CT scans. Attenuation values of intraluminal filling defects of the IVC ranged from 38 to 42 H in four patients. High-attenuation intraluminal filling defects (60-70 H) of the IVC (five patients) and hepatic veins (one of five patients) were detected. Of these five patients, four had acute symptoms and one had chronic vague symptoms. The underlying disease was a web or band in the IVC and hepatic veins in three patients, invasive hepatocellular carcinoma in one, and injury to the IVC wall during hepatectomy in one. Inferior venacavography showed occlusion of the hepatic segment of the IVC in all five patients. Additional angiograms obtained by injection of contrast medium after a catheter tip was placed in the occluded hepatic IVC showed numerous filling defects suggestive of thrombi of recent onset, which correlated with the high-attenuation thrombi seen on CT scans in two patients. In the remaining three patients, high-attenuation areas in the IVC and hepatic veins also were considered to represent thrombi of recent onset because the attenuation values later decreased to 33-42 H. Spontaneous reduction in diameter of the thrombosed segment of the IVC was observed in four of the five patients. Knowledge of the CT features of acute thrombosis of the IVC and hepatic veins is useful in the early diagnosis of Budd-Chiari syndrome.     

Aneurysms of the inferior vena cava

Two cases of saccular aneurysms of the infrarenal inferior vena cava (IVC) associated with retrohepatic IVC obstruction are described. Ultrasonographic, computerized tomographic and inferior venacavography findings in these cases are presented.     

Imaging primary and secondary tumor thrombus of the inferior vena cava: multi-detector computed tomography and magnetic resonance imaging

Tumor thrombus of the inferior vena cava (IVC) is a severe medical condition with very poor prognosis unless the patient is treated with surgical resection. It can be caused by a primary leiomyosarcoma originating in the vessel wall or by intraluminal extension of tumor thrombus into the IVC from an adjacent organ. We reviewed 21 cases of tumoral thrombus in the IVC including primary leiomyosarcoma of the IVC (2 cases), renal cell carcinoma (14 cases), adrenocortical carcinoma (2 cases), primary adrenocortical leiomyosarcoma (1 case), hepatocellular carcinoma (1 case), and retroperitoneal metastasis (1 case). The most common findings of IVC tumor thrombus by multi-detector CT and magnetic resonance imaging will be discussed, including scanning protocols and the advantages and disadvantages of each method.     

下腔静脉隔膜阻塞型布-加综合征的病理学及病因学研究

目的研究下腔静脉隔膜阻塞型布-加综合征(BCS)的解剖位置和隔膜病理特点,以探讨病因及发病机制。方法分析100例非BCS死亡成人解剖资料,进行下腔静脉膈肌以上至右心房的大体观察。常规显微镜病理检查70例下腔静脉隔膜阻塞型患者的隔膜活检材料及20例BCS患者根治术后切除的完整隔膜。结果大体观察发现1例(1%)在位于平膈肌水平距下腔静脉入右心房28mm处、肝静脉开口上方的左外侧壁,存在一瓣膜;47%成人位于下腔静脉近右心房口存在Eustachian瓣。镜检显示,上述全部隔膜符合血管瓣膜样结构。其中30%(21/70)样本附有机化血栓。9%(6/70)样本内有少量炎细胞浸润。全部完整隔膜病理检查与血管壁相延续。结论首次报道在位于下腔静脉平膈肌水平有一瓣膜,这一瓣膜的发现,可能与下腔静脉隔膜阻塞型BCS的发生高度相关。     

Benign external compression of the inferior vena cava associated with thrombus formation

Malignant and benign causes of inferior vena cava (IVC) occlusion and compression are recognized. Cases of benign IVC compression with associated distal thrombus formation have not however been frequently described. We present two cases of benign external IVC compression associated with distal thrombus formation; one resulting from a giant, benign, hepatic cyst, and another due to pelviureteric junction obstruction, resulting in massive hydronephrosis.     

Hepatic inferior vena cava obstructions: clinical results of treatment with percutaneous transluminal laser-assisted angioplasty

Three cases of hepatic inferior vena cava (IVC) obstruction (two segmental and one membranous) associated with Budd-Chiari syndrome were successfully treated with percutaneous transluminal angioplasty (PTA) with use of an Nd-YAG (neodymium-yttrium, aluminum, garnet) laser. The occluded portions were canalized by advancing a ceramic-capped delivery system and delivering intermittent laser emissions. The canal was widened by simultaneous inflation of three or four Gruentzig balloon catheters. In two of the three cases, this procedure was done after unsuccessful canalization of the occluded portions by conventional means. Postoperatively, all patients showed disappearance of Budd-Chiari syndrome. One patient also showed marked regression of a huge intraluminal thrombus. There were no serious complications during and after the procedures. Use of the Nd-YAG laser seems to be of value in PTA for the treatment of hepatic IVC obstructions as well as in treatment of arteriosclerotic lesions.     

The use of radionuclide venography in the differential diagnosis of inferior vena caval obstruction

In using radionuclide imaging of the inferior vena cava (RIVC) to investigate the prevalence of membranous obstruction of the inferior vena cava (IVC) in patients with hepatocellular carcinoma, it was necessary first to determine if this technique would distinguish membranous obstruction of the IVC both from other causes of IVC obstruction likely to be encountered in these patients and from the picture obtained with severe ascites. RIVC readily distinguished an obstructed from a normally patent IVC. However, membranous obstruction of the IVC could not in most instances be differentiated from extrinsic compression of the IVC by an enlarged tumourous liver, occlusion of the lumen of the IVC by tumour, or the effect of severe ascites. In a proportion of the patients with membranous obstruction of the IVC, flow of the radionuclide through large superficial collateral vessels was seen, enabling this diagnosis to be made with confidence. Thus, if RIVC shows the IVC to be obstructed or if severe ascites is present, contrast venography will usually be necessary to determine the nature of the obstructing lesion.     

Membranous obstruction of the inferior vena cava associated with intrahepatic portosystemic shunt

Two cases of membranous obstruction of the IVC at hepatic portion associated with intrahepatic portosystemic shunts, which presumably represent the persistent vitelline sinusoids, are presented. The association of these two conditions has not been previously reported and may support the congenital etiology of the membranous obstruction of the IVC. The caval membrane was successfully dilated percutaneously with a balloon catheter in each case.     

Budd-Chiari综合征下腔静脉病变的多排螺旋CT诊断

目的探讨Budd-Chiari综合征(BCS)下腔静脉阻塞病变的多排螺旋CT(MSCT)表现及其诊断价值。方法对比分析14例BCS下腔静脉的MSCT和血管造影表现。结果下腔静脉造影证实下腔静脉膜性狭窄2例、膜性闭塞9例、节段性闭塞3例;下腔静脉内血栓形成6例;下腔静脉闭塞区钙化4例;下腔静脉远心端皆有不同程度的扩张增粗。MSCT显示的下腔静脉狭窄和闭锁病变、有无血栓形成以及下腔静脉的走行均与下腔静脉造影相符合;并能显示下腔静脉阻塞区近心端到右心房入口的距离。结论MSCT能全面显示BCS下腔静脉的病变情况,诊断价值高,能可靠的指导制订下腔静脉阻塞的治疗方案。     

Hepatic changes in benign obstruction of the hepatic inferior vena cava: CT findings.

OBJECTIVE: The objective of this study was to describe CT findings of changes in the liver associated with benign obstruction of the hepatic inferior vena cava (IVC). MATERIALS AND METHODS: For a 10-year period, 35 patients with benign obstruction of the hepatic IVC underwent contrast-enhanced CT of the abdomen. These patients were included in this retrospective study. CT scans were analyzed for morphologic changes and abnormal enhancement of the liver, changes in intrahepatic vessels, and additional findings that might be related to obstruction of the IVC. RESULTS: Morphologic changes of the liver included hypertrophy of the caudate lobe (91%) and the left lobe (57%), atrophy of the right lobe (49%), and a nodular surface (74%). The most common pattern of attenuation change was areas of linear, irregular, or wedge-shaped hypoattenuation predominantly located in the peripheral portion of the liver (63%). Diffuse hypoattenuation was seen in six patients (19%) and was frequently found in areas in which hepatic veins filled with hypoattenuated thrombosis (67%). On CT, segmental IVC obstruction (80%) was seen as an obliterated segment of the hepatic IVC. However, membranous IVC obstruction (20%) was not seen on CT. The IVC below the level of obstruction was often revealed as rounded (89%) and occasionally contained thrombus (37%) or calcification (26%). CONCLUSION: CT shows a broad spectrum of morphologic and attenuation changes of the liver and of the hepatic vessels in benign obstruction of the hepatic IVC.     

Primary leiomyosarcoma of inferior vena cava, a rare entity: Imaging features

Leiomyosarcoma of the inferior vena cava (IVC) is an uncommon neoplasm, most frequently seen in the sixth decade with a female predominance. Imaging modalities allow an early and accurate preoperative diagnosis resulting in a higher rate of surgical resection and improved survival. Imaging findings in a 65-year-old woman with leiomyosarcoma of IVC are described. Computed tomography and MRI typically showed a non-fatty, necrotic intraluminal IVC mass with extension to retroperitoneal compartments. Cavography was useful to evaluate the collateral circulation associated with the extensive intraluminal mass. The lesion was biopsied under ultrasound guidance.     

Ultrasonically guided inferior vena cava stent placement: experience in 83 cases

PURPOSE: Traditionally, inferior vena cava (IVC) stent placement is performed with fluoroscopic guidance. The object of this study was to evaluate use of ultrasound (US) as guidance for IVC stent placement for the management of Budd-Chiari syndrome. MATERIALS AND METHODS: Eighty-three patients with IVC membranous stenosis (n = 30), membranous occlusion (n = 19), segmental stenosis (n = 21), or segmental occlusion (n = 13) underwent IVC recanalization, balloon dilation, and stent placement under US guidance. Among the 83 patients, 67 had at least one patent hepatic vein, while 16 patients had three occluded hepatic veins. RESULTS: IVC stents were successfully placed in 79 of 83 patients, with a success rate of 95%. After the procedure, the symptoms and signs of IVC obstruction disappeared or markedly improved in all patients, and the blockage of hepatic outflow was alleviated in 67 patients. Pericardial effusion, complete atrial ventricular block, and stent migration into the right atrium occurred, respectively, in one patient. During 1-46-month follow-up, stent restenosis occurred in one patient; the other stents remained open and functioned effectively. CONCLUSION: Because of the absence of nonionizing radiation and iodinated contrast material, and its low cost, US is well suited and often preferred for guidance of IVC stent placement.     

肝移植术后肝静脉和下腔静脉梗阻的诊断及介入治疗

目的 探讨肝移植术后肝静脉、下腔静脉梗阻的诊断及介入治疗技术.方法 在831例原位肝移植(OLT)、26例活体肝移植(LDLT)患者中,共有11例在移植术后2～111 d经血管造影证实为肝静脉、下腔静脉梗阻并进行了介入治疗.其中肝静脉吻合口狭窄或闭塞5例、下腔静脉吻合口狭窄5例、肝静脉狭窄伴下腔静脉吻合口狭窄1例.11例中,5例为成人OLT、4例为LDLT、2例为儿童减体积OLT,介入治疗前9例接受了肝脏CT、2例接受了MR增强扫描.术后随访患者肝肾功能指标、临床症状及肝静脉、下腔静脉血流状况.对11例患者的影像资料、介入治疗技术要点和治疗效果进行回顾性分析.介入治疗前后梗阻两端静脉压力差比较,采用配对t检验.结果 11例患者,CT或MR检查均可明确显示肝脏淤血范围、肝静脉或下腔静脉梗阻部位及程度;其中4例肝静脉梗阻和5例下腔静脉梗阻者行支架植入治疗,1例肝静脉梗阻者行经皮腔内血管球囊扩张术(PTA),1例肝静脉伴下腔静脉梗阻者,行肝静脉PTA和下腔静脉支架植入,介入治疗手术均成功.术后检测梗阻两端静脉压力差为(2.9±1.7)mm Hg(1 mm Hg=0.133 kPa),较术前(16.5±4.1)mm Hg明显下降(t=11.5,P＜0.01).术后10例患者临床症状改善,肝肾功能恢复;1例肝功能恶化,于术后第9天死于多器官功能衰竭.患者术后随访9～672 d,2例肝静脉PTA治疗者术后1个月内发生血管再狭窄,支架植入治疗者未发生再狭窄,无严重并发症发生.结论 支架植入是治疗肝移植术后肝静脉和下腔静脉梗阻安全、有效的方法;术前CT或MR对明确肝淤血范围及静脉梗阻具有重要价值.     

Abdominal venous system: assessment using MR

Twenty-five patients with known or suspected evidence of venous disease based on results of computed tomography, angiography, or ultrasound were imaged with magnetic resonance (MR) to determine the MR characterization of venous abnormalities. MR findings were proved by laparotomy or autopsy in 18 of 25 cases. In seven of 25 patients in whom only biopsy was performed, the MR findings were correlated with findings from other radiologic tests. On MR, the inferior vena cava (IVC), portal vein, and their major tributaries were seen in all but two cases. In those two, identification of collaterals led to the correct diagnosis of splenic vein thrombosis in one case and left renal vein thrombosis in another. MR imaging helped identify intraluminal thrombi in the IVC (12 of 12 cases), portal vein (two of two cases), renal veins (seven of seven cases), superior mesenteric vein (one case), and iliac veins (seven of seven cases). Intraluminal signal intensity secondary to slow blood flow seen in five patients was always differentiated from the thrombus. MR imaging helped identify correctly the nature of the thrombus in 11 of 16 patients. In five patients, the differentiation between tumor thrombus and blood clot thrombus was not possible. Involvement of the IVC wall by tumor was seen in four cases. MR imaging also accurately depicted slow flow in obstructed or constricted veins; encasement, compression, or displacement of veins without intraluminal occlusions; and the presence of venous collaterals. The MR imaging evaluation of venous abnormalities is accurate, easily performed, and will probably become an important application.     

Computerized tomography in the follow-up of inferior vena cava filters

CT was employed to evaluate IVC filters in 37 patients; most devices (25) were Greenfield filters. Filters were localized below the renal veins in 26 patients; a suprarenal position was observed in 11 cases. Filter malpositioning was shown by CT in 1 case (filter partially located in the left renal vein); migration of the device into left pulmonary artery was detected in 1 patient. IVC perforation occurred in 11 cases--in 6 of them, the filter penetrated into adjacent structures (duodenum in 2 cases, abdominal aorta in 2, liver in 1, and right kidney in 1 patient). IVC thrombosis was seen in 16 patients; complete caval obstruction developed in 2 cases two or more years after filter positioning. IVC perforation caused by a filter is a frequent complication (30% of our series), but in most cases it is asymptomatic and has no significant clinical relevance; surgical removal of the filter had to be performed in 3 cases only. CT scanning is a valuable adjunct to plain abdominal radiography in the follow-up of IVC devices, when a complication (especially IVC perforation) is suspected.     

下腔静脉阻塞端形态和破膜方法选择的临床研究

目的探讨下腔静脉阻塞端形态和破膜方法选择的关系。方法我科自2003-2005年收治155例下腔静脉阻塞病例,根据下腔静脉造影表现,对阻塞近心端和远心端形态进行分类和统计,根据不同形态分别采用自上向下或自下向上穿刺破膜。并以1990-1997年治疗的150例下腔静脉阻塞病例作为对照组,统计分析破膜穿刺时并发症的发生率。结果本组155例病例中,下腔静脉阻塞远心端形态可分为7种,即膜中有孔形(32例)、圆弧形(50例)、锥形(17例)、水平形(13例)、斜形(10例)、不规则形(19例)和伴交通支形(14例);阻塞近心端形态主要分为膜中有孔形、圆弧形、锥形和水平形。本组病例全部破膜开通成功,无一例发生心脏压塞和腹腔出血。对照组150例下腔静脉阻塞型布加综合征病例,在破膜中误穿心包16例,下腔静脉扩张后腹腔内出血2例。两组比较,严重并发症发生率差异具有统计学意义。结论破膜是下腔静脉阻塞介入开通术中的关键步骤,根据阻塞端的形态选择合适的破膜穿刺方向不仅可以提高破膜成功率,更可以减少并发症。