Excessive anteriorisation of the superior vena cava associated with an azygos lobe

Summary A wide variety of congenital vascular anomalies of the superior mediastinum exist. Being clinically silent, most of these anomalies are detected incidentally on plain radiographs or CT scans where they could be mistaken for mediastinal masses. Familiarity with these anomalies is very important for correct interpretation and avoidance of confusion. We present a case of a mediastinal mass detected accidentally on plain radiography which on further radiological investigation was found to be an unreported normal variant of the superior vena cava (SVC). CT scans of the thorax and superior vena cavograms showed excessive anteriorisation of the SVC in the presence of an azygos lobe. After reviewing the literature and the embryology of the SVC and azygos lobe, we postulate that the variation in the location of the SVC was possibly due to the presence of the azygos lobe.

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Ventralisation excessive de la veine cave supérieure associée à un lobe azygos

Résumé Il existe une grande variété d'anomalies vasculaires congénitales du médiastin supérieur. Le plus souvent cliniquement silencieuses, ces anomalies sont alors détectées incidemment sur des radiographies ou des scanners où elles peuvent être prises pour des masses médiastinales. La connaissance de ces anomalies est très importante pour une interprétation correcte des documents et éviter toute confusion. Nous présentons le cas d'une masse médiastinale détectée fortuitement sur une radiographie qui s'avéra être, sur des investigations radiologiques complémentaires, une variation non rapportée de la v. cave supérieure (VCS). Le scanner thoracique et la phlébographie cave supérieure ont montré une ventralisation excessive de la VCS et la présence d'un lobe azygos. Après avoir relu la littérature et revu l'embryologie de la VCS et du lobe azygos, nous pensons que cette variation de l'emplacement de la VCS peut être due à la présence du lobe azygos.

     

肝尾状叶脉管构筑的应用解剖

应用55例成人肝剥离标本及45例胎儿、新生儿肝管道铸型,研究了肝尾状叶的鞘系及静脉回流。尾状叶有两个恒定的蒂、接受左、右侧鞘系的双重供应,以左侧为主;而尾状突主要由右后叶鞘系分布。15例肝铸型标本的尾状叶左、右侧动脉形成吻合弓。尾状叶动脉供应形式可分为三种,静脉可分为三型并直接汇入下腔静脉。由于血管吻合的存在,在病理状态下,尾状叶也应是沟通门一腔静脉的桥梁。     

The caudate lobe of the liver

Summary The caudate lobe of the liver is an independent segment straddling the right and left lobes of the liver. It is divided into 2 parts, right and left, indicated eternally by the caudate and papillary processes. It is now possible to unvestigate it by ultrasonography and computed tomography, allowing its surgical excision for tumoral disease of the superior biliary confluence.

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Le lobe caudé du foie

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Résumé Le lobe caudé du foie est un secteur indépendant à cheval sur les foies droit et gauche. Il est séparé en 2 parties droites et gauches, marquées extérieurement par les processus caudé et papillaire. Son exploration est actuellement possible (échographie et tomodensitométrie), ce qui autorise son exérèse chirurgicale (pathologie tumorale du confluent biliaire supérieur).

     

Three cases of amoebic liver abscess causing inferior vena cava obstruction,with a review of the literature

Amoebic liver abscess is a common disease, especially in endemic areas, but it is a rare cause of inferior vena cava (IVC) obstruction, with only a few cases appearing in the literature. We report three cases of amoebic liver abscess complicated with obstruction of the IVC and which responded to conservative treatment or radiological intervention.     

双下腔静脉畸形合并静脉血栓栓塞症介入治疗方法探讨

目的 探讨双下腔静脉(IVC)畸形合并静脉血栓栓塞症(VTE)的介入治疗方法。方法 回顾性分析2009年6月—2014年7月徐州医学院附属医院收治的5例双IVC畸形合并VTE患者的临床资料。其中男4例,女1例;年龄28～76岁,平均 49岁。患者均采用可回收IVC滤器置入联合经导管溶栓治疗。术后观察患者临床症状改善情况,定期随访,采用彩色多普勒超声观察IVC及下肢静脉通畅情况。结果 本组5例患者均顺利完成手术,术中共置入滤器5枚,其中2例滤器置于总IVC,2例置于左IVC,1例置于右IVC。术中出现IVC血栓脱落致肺栓塞1例,经溶栓治疗后治愈。术后5例患者临床症状完全消失,经导管溶栓治疗5~12 d(平均7 d)血栓均完全溶解,滤器留置6~14 d后成功取出。无出血、滤器倾斜或移位等并发症。5例患者均获随访3~60个月。随访期间,1例患者术后3个月死于胃癌复发;其余患者无血栓复发,彩色多普勒超声检查显示IVC及下肢深静脉血流均通畅。结论 对于双IVC畸形合并VTE患者,根据血栓部位、双IVC走行及交通血管情况,采用可回收滤器置入联合经导管溶栓治疗,方法安全,效果可靠。     

Ieiomyosarcoma of the superior vena cava producing superior vena cava syndrome and heart tamponade

An autopsy case of primary leiomyosarcoma arising in the superior vena cava is presented. A 44 year old Japanese man presented with superior vena cava syndrome and eventually died due to heart tamponade and acute renal failure. Autopsy revealed that the superior vena cava was occluded with a tumor that had invaded the pericardium and right thoracic cavity. Primary caval venous leiomyosarcoma is a rare but lethal disease and most cases arise from the inferior vena cava. This case represents a very rare case of leiomyosarcoma with the rare clinical findings of superior vena cava syndrome and heart tamponade.     

肝尾状叶应用解剖学研究方法的设计与比较

目的为临床应用解剖学系统研究肝尾状叶位置、形态、毗邻,血管系来源、走形、分布及胆道系,设计简易、高效,具有针对性研究方法,以期为肝尾状叶切除术提供形态学理论基础。方法选用防腐与新鲜管道灌注的肝脏,采用大体解剖、断层、管道铸型、管道造影术等方法,对肝脏尾状叶进行系统的解剖学研究。结果上述各方法均能清晰地显示肝尾状叶位置、形态、毗邻、血管系来源,及胆道系统,但各具特色。大体解剖法清楚明确地显示肝尾状叶位置、形态、界邻结构;断层法通过不同方向的肝断面,清楚准确地展示和表述诸结构的断面形态、位置及毗邻;管道铸型法清晰直观地显示肝尾状叶内部管道结构;管道造影法使标本在CT机、MRI扫描后,获得数据集,利用Mimics10.01、3D-Doctor、Amkira4.1等电脑软件,能进行肝脏尾状叶外表和内部结构3D可视化。结论大体剖制法、断层法、管道铸型法、管道造影术等是系统研究肝脏尾状叶位置、形态、毗邻和内部管道结构有效的方法。     

Vascular leiomyosarcoma arising from the inferior vena cava diagnosed by intraluminal biopsy

 A 61-year-old woman developed pain in the right thigh, paraplagia of the lower extremities and lumbago in November 1996. A lumbar spine roentgenogram showed lytic change in L2, and magnetic resonance imaging showed a patchy destructive lesion and compression of the dural sac from the right by a tumour. Computed tomography (CT) myelography showed a motheaten destructive lesion in L2 and projection of the tumour into the spinal canal. Abdominal ultrasound, CT and cavography showed dilatation of the inferior vena cava (IVC) and an intraluminal tumour about 2×2.8×4 cm in size in the IVC. The tumour arose from the IVC just beneath the renal vein and extended to just short of the right atrium. Both vertebral and intraluminal biopsy materials showed the same morphology, in which atypical spindle cells admixed with multinucleated giant cells proliferated in a fascicular growth pattern. Neoplastic cells were strongly positive for alpha-smooth muscle actin. We diagnosed vascular leiomyosarcoma arising from the IVC with metastasis to the lumbar vertebrae. Cases of vascular leiomyosarcoma diagnosed by intraluminal biopsy are rare. Received: 25 November 1997 / Accepted: 5 February 1998     

Radiological evidence of anatomical variation of the inferior vena cava: Report of two cases

The inferior vena cava (IVC) is a retroperitoneal key structure whose location and integrity must be checked in every scan. A number of studies are reported in the literature concerning congenital variations of the inferior vena cava. Anatomical variations of this main venous trunk are relatively infrequent clinical findings during surgery or diagnostic procedures in patients without symptoms such as an aberrant venous drainage or abdominal pain. Among the other imaging techniques, computerized tomography is a non-invasive, effective technique for diagnosing diseases of the retroperitoneal space and, particularly, for detecting anomalies of the main vessels, such as the aorta or IVC, in asymptomatic patients. We present two cases of IVC variation as an incidental finding in patients studied by means of CT scan for the gradation of kidney carcinoma and pancreatic cancer respectively. Two different configurations of the system of the IVC (agenesis of the IVC with hypertrophy of the azygos vein and a double IVC respectively) were found in our cases. The embryological development of the IVC system is discussed, bearing in mind that knowledge of the different variations is important in order to avoid major surgical complications.     

双下腔静脉的MSCT表现及临床意义

目的　探讨双下腔静脉（inferior vena cava,IVC）的多层螺旋CT（multi-slice spiral CT,MSCT）表现及临床意义。 方法　收集经腹部MSCT多期增强扫描发现的18例双IVC患者,采用MPR、MIP和VR等血管成像技术显示IVC解剖,回顾性分析患者临床及影像学资料,结合文献讨论双IVC影像学特征、胚胎学机制及临床意义。 结果　18例双IVC的MSCT表现为3种类型。Ⅰ型83.33%（15例）表现为左侧IVC上行至左肾静脉汇入,再以左肾静脉正常方式经主动脉前方右行,汇入正常的右侧IVC。Ⅱ型11.11%（2例）表现为右侧IVC上行达腰2椎体平面,经腹主动脉后方左行汇入左侧IVC,后者再上行延续为半奇静脉,然后经奇静脉和上腔静脉汇入右心房;右肾静脉主要汇入右侧肾上段IVC,但存在侧支与右侧肾下段IVC相连。Ⅲ型5.56%（1例）表现为右侧IVC全程行径正常,左侧IVC垂直上行接收左肾静脉汇入后,于主动脉后方向右上走行与奇静脉连接。 结论　双IVC有多种复杂的变异类型,对于腹膜后手术及下半身静脉血栓治疗具有重要的临床意义。     

Preureteric inferior vena cava with possible rudiment of the proper inferior vena cava

A right single preureteric inferior vena cava (IVC) was found in the cadaver of a 77-year-old Japanese male during a student dissection course at Kumamoto University School of Medicine in 2003. The ureter emerged from the lower end of the hilum of the right kidney at the second lumbar vertebral level. It ran inferomedially to pass behind the IVC, and turned inferolaterally to cross the vein superficially at the level of the third to the fourth lumbar vertebrae. Then, the ureter was situated to the right of the IVC, and descended ordinarily. The second lumbar vein of each side united bilaterally, as did the third lumbar veins. The common stem of the second lumbar veins drained into the left side of the IVC posterolaterally at the level of the second intervertebral disc, and the third common stem opened into the left border of the IVC at the fourth lumbar vertebral level. The ureter hooked around the IVC between the openings of those common stems. There was a small continuation (0.2 mm in diameter) between the left second lumbar and the right third lumbar veins along the vertebral column slightly right of the midline. It passed superficial to the right third lumbar artery, as did the IVC. The right testicular vein opened into the IVC at the level of the lower end of the third lumbar vertebral body. Generally, the level of the opening of the gonadal vein corresponds to the level of the caudal end of the remaining subcardinal vein, but it is lower than usual in this case. Furthermore, the segment from the confluence of the common iliac veins to the common trunk of the third lumbar veins, and to the small continuation can be regarded as the proper IVC, and the part where the ureter hooks around it may have derived from the anastomosis between the common trunk of the third lumbar veins and the subcardinal vein.     

Hydrodynamics of blood flow through the inferior vena cava

The inferior vena cava (i.v.c.) is a collapsible vessel which is subject to respiratory pressure variations. Clinical observations on humans show that, during deep inspiration, an increase in the propulsive pressure gradient causes the i.v.c. to collapse near the diaphragm and paradoxically reduces the blood flow. Postmortem casts show that there is a sharply localised elastic constriction where the i.v.c. passes through the diaphragm. A passive mechanical model, incorporating a similar elastic constriction, exhibits similar paradoxical or negative-resistance behaviour, which is in accordance with the principles governing flow through collapsible tubes.     

Geometrical variations of the canine superior vena cava: Relationship between diameter,segment length and transmural venous pressure

The dimensional variations of the superior vena cava throughout the cardiac cycle were investigated by means of angiographic and ultrasonic techniques. Results obtained by both methods were largely in agreement. In frontal direction the diameter curve resembled the transmural pressure variations, the sagittal diameter curve was not related to the venous pressure variations during certain phases of the cardiac cycle and compressional and/or stretching forces exerted by respectively the distending aorta and/or pulmonary artery and the contracting heart may have been responsible. Also segment length variations occurred: during atrial contraction, ventricular systole and early diastole the vein elongated, indicating the varying longitudinal traction forces, possibly exerted by the rotational movement of the contracting heart. Assuming elliptical symmetry the vena caval cross-section could be reconstructed, and the cross-sectional area, perimeter and segmental volume could be calculated throughout the cardiac cycle. Despite the high venous distensibility, no extreme collapse of the vein was observed during the cardiac cycle at low transmural pressures.     

尾状叶切除术的应用解剖

目的：通过肝尾状叶的应用解剖学研究,为肝脏尾状叶切除术的入路和发展提供解剖学基础。方法：通过40具尸肝尾状叶标本的解剖观察和8具肝脏铸型标本的观察研究,揭示尾状叶的形状、边界、毗邻和血管胆管分布规律。结果：①尾状叶左侧的形态、大小、边界变异不大,其血液供应胆管引流有一个相对固定的“蒂”,手术切除比较容易;②尾状叶的血管供应胆管引流繁杂,但均连接于Glisson's管的一二级分支的前上缘,沿肝门板后方向上解剖找出尾状叶“蒂”,从中再解剖动脉、门静脉、胆管易行,甚至一起结扎、切断也可;③肝短静脉数量、注入部位变异大,然而其走行多与腔静脉壁垂直,顺着方向解剖比较安全。结论：尾状叶切除的手术入路有四条：左入路、右入路、前入路和后入路。     

Fetal development of the retrohepatic inferior vena cava and accessory hepatic veins: Re‐evaluation of the Alexander Barry's hypothesis

The retrohepatic inferior vena cava (IVC) is commonly considered to originate from the right vitelline or omphalomesenteric vein. In contrast, Alexander Barry hypothesized that one of the hepatic veins grows to merge with the subcardinal vein and develops into the retrohepatic IVC. We re‐examined fetal development of the retrohepatic IVC and other related veins using serial histological sections of 20 human fetuses between 6 and 16 weeks of gestation. At 6–7 weeks, when a basic configuration of the portal‐hepatic vein systems had just been established, one of hepatic veins (i.e., the posterocaudal vein in the present study) had grown caudally to reach the posterocaudal surface of the liver, and notably, extended into the primitive right adrenal gland (five of the eight early‐staged fetuses). Because the inferior right hepatic vein (IRHV) and retrohepatic IVC appeared at the same developmental stage, it is likely that any peripheral remnants of the posterocaudal vein would continue to function as primary drainage territory for the IRHV. The caudate vein developed rapidly in accordance with marked caudal and leftward extension of Spiegel's lobe at 12–16 weeks. Thin accessory hepatic veins developed later than the caudate vein and IRHV. The present results supported Barry's hypothesis. Clin. Anat. 23:297–303, 2010. © 2010 Wiley‐Liss, Inc.     

Primary liver carcinoma complicating membranous obstruction of the inferior vena cava

A rare autopsy case of primary liver carcinoma complicating a pre-existing, incomplete membranous obstruction of the inferior vena cava (MOVC) is reported. The patient, a 67-year-old Japanese male, was admitted to hospital following a 2 year illness of a left chest wall tumor and a 3 month illness with progressive abdominal pain. Computed tomography scans of the abdomen displayed space-occupying lesions in the third and seventh hepatic segments, respectively. One month later, the patient developed edema of the lower extremities and marked venous dilatation of the abdominal trunk. At that time, Doppler examination revealed the presence of intrahepatic large venovenous collaterals. The patient subsequently succumbed 82 days after hospitalization. At subsequent autopsy, the inferior vena cava was completely obstructed by tumor thrombus, which was formed caudally and cranially to a thin membrane and mimicked the valve, with calcification and elastic lamina, at the phrenic portion. Intrahepatic large collateral pathways were found between submembranous and supramembranous hepatic veins. Anomalous absence of the ostia of the middle hepatic vein was found. In addition, the portal venous trunk was occluded by tumor thrombus. Histology of hepatic tumors revealed a combined hepatocellular and cholangiocellular carcinoma in the non-cirrhotic liver with severe acute centrilobular congestion. In MOVC patients such as the case presented, malignancy-induced thrombosis was deemed to be an important factor in prognosis.     

Abscess of the caudate lobe of the liver,a rare disease with a challenging management: a case report

We reported a rare case of abscess of the caudate lobe of the liver in a 60-year old man. We first tried computed tomography (CT) guided percutaneous drainage of the abscess but failed to eradicate the infection. Deterioration of the general condition of the patient necessitated open surgical drainage, which resulted in cure of the abscess. The peculiar anatomical location of caudate lobe abscess introduces a great challenge for the surgeon in planning the appropriate management and paucity of patients with caudate lobe abscess has led to lack of guidelines for management. The non-operative interventional radiology approach has become the therapeutic choice for pyo?genic liver abscess, but is it applicable also for caudate lobe abscess?     

Diameter of the superior vena cava in the newborn: clinical applications in parenteral nutrition

Summary The authors measured the superior vena cava in the newborn by radiologic, anatomic and histologic methods and analysed the correlations between cross-sectional area and the biometric data. This method makes it possible to select the size of catheter for parenteral nutrition via the superior vena cava in relation to body-weight.

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Le calibre de la veine cave supérieure chez le nouveau-né

Résumé Les auteurs analysent sur 46 mesures de la veine cave supérieure chez le nouveau-né (mesures radiologiques, anatomiques et histologiques), les corrélations entre la section de la veine et les constantes biométriques de l'enfant. Cette méthode permet de prévoir la taille des cathéters centraux cave supérieur que l'on utilise en clinique, en fonction du poids de l'enfant.

     

Intravascular epithelioid hemangioendothelioma of the inferior vena cava: case report of an unusual and unpredictable vascular tumor

Vascular neoplasms are uncommon and pose a diagnostic and treatment challenge to the pathologist and surgeon, respectively. Epithelioid hemangioendothelioma is a rare neoplasm of vascular origin with an unknown etiology. Its biologic behavior lies somewhere between that of a benign hemangioma and that of a malignant angiosarcoma; however, it is unpredictable at best. Intravascular epithelioid hemangioendotheliomas have been described more often in veins than arteries, and there are only about 30 reports in the English literature. We report here the case of an epithelioid hemangioendothelioma of the inferior vena cava, which presented with abdominal pain, ascites and pedal edema.