CT diagnosis of renal vein thrombosis in nephrotic syndrome

Forty-seven patients with nephrotic syndrome were prospectively studied for renal vein (RVT) and inferior vena caval (IVCT) thrombosis with dynamic CT. Renal venography and inferior vena cavography was performed on the 12 patients with and on 5 of the patients without CT evidence of thrombosis. Dynamic CT revealed thrombi in 12 of 47 (26%) of the cases (RVT in 8, IVCT in 5); all were confirmed by venography. In one of the cases with RVT, a thrombus in a superior branch of the left renal vein was revealed by venography but not by CT. Venography was normal in all five patients evaluated with normal dynamic CT. We believe that dynamic CT can be used to effectively examine patients with suspected RVT.     

Renal vein and inferior vena cava tumor thrombus in renal cell carcinoma: CT, US, MRI and venacavography.

Renal cell carcinoma has a propensity to extend as tumor thrombus into the renal vein and inferior vena cava (IVC). The preoperative assessment for the presence and extent of renal vein and IVC tumor thrombus is important for planning appropriate surgical resection. Imaging procedures [CT, ultrasound (US), MR, venacavography] were correlated with surgical findings and pathology in 431 consecutive patients who had a radical nephrectomy for renal cell carcinoma. Ninety-nine (23%) patients had tumor thrombus extending at least into the main renal vein. Of these, 29 had tumor thrombus extending within the IVC. Patients were classified into two groups based on the surgical extent of tumor thrombus. Group A patients had no tumor thrombus or had tumor thrombus only in the renal vein proximal to the site of surgical ligation. Group B patients had tumor thrombus that extended to or beyond the distal renal vein at the site of surgical ligation. Forty-one patients had Group B tumor thrombus. Group B tumor thrombus was not seen in a renal cell carcinoma that was smaller than 4.5 cm. The sensitivity of CT for detecting Group B tumor thrombus was 79% and that of US was 68%. However, a much higher percentage of US examinations were technically indeterminate. In the patients who had either MR or venacavography, both imaging procedures were 100% sensitive for detecting group B tumor thrombus. Magnetic resonance imaging and venacavography appear to be the most sensitive means of identifying tumor thrombus.     

下腔静脉畸形的64层螺旋CT表现

目的 探讨64层螺旋CT下腔静脉畸形的影像表现.方法 回顾性分析6986例受检者的腹部64层螺旋CT增强扫描资料,共发现25例下腔静脉先天畸形.分析下腔静脉畸形的影像表现.结果 25例下腔静脉畸形中包括左下腔静脉6例,CT表现为肾下段腹主动脉左侧上行的下腔静脉.双下腔静脉10例,CT表现为肾下段腹主动脉两侧上行的下腔静脉.左肾静脉畸形5例,CT增强扫描横断面显示腹主动脉后和环主动脉走行的左肾静脉.肝下段下腔静脉中断伴奇静脉延续2例,胸腹部CT增强扫描显示肝段至肾上段下腔静脉缺如,肾段下腔静脉由奇静脉延续回流人上腔静脉,而肝静脉直接回流右心房.腔静脉血管造影见对比剂经增粗的奇静脉和半奇静脉通过上腔静脉回流右心房.肝下段下腔静脉中断伴门静脉延续1例,增强CT显示下腔静脉直接与门静脉在肝门部连接,肝门部门静脉呈瘤样扩张.左下腔静脉伴半奇静脉延续1例,增强CT可见左下腔静脉与半奇静脉连接,上行汇入奇静脉.结论 64层螺旋CT可清晰显示下腔静脉及其属支的畸形,可成为下腔静脉畸形的重要诊断方法.     

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.     

Suprarenal inferior vena cava filter implantation

Purpose

This study evaluated the feasibility, safety, and efficacy of the suprarenal implantation of a retrievable filter in patients with renal cell carcinoma (RCC) and renal vein thrombosis (RVT) [extending or not extending to the inferior vena cava (IVC)] undergoing surgery.

Materials and methods

Between March 2005 and May 2010, 13 patients (eight men and five women; mean age 67.08 years, range 38?C95) with RCC and RVT associated or not with IVC thrombosis underwent implantation of a retrievable suprarenal IVC filter. All patients underwent computed tomography angiography (CTA), which documented RVT and in some cases its extension to the IVC. The level of IVC involvement by the neoplastic thrombus was evaluated on the basis of the Oto classification. Cavography was performed before and after filter implantation. Surgical resection of RCC was performed in all patients. A CTA scan was performed 1 week before filter removal.

Results

The procedure had 100% feasibility. All filters were correctly deployed in the suprarenal tract of the IVC. There was no evidence of peri-or postprocedural complications. All patients were monitored for clinical symptoms of pulmonary embolism (PE). There was no evidence of PE in the 30 days after the procedure. All suprarenal IVC filters were removed from 30 to 60 days after surgery.

Conclusions

Implantation of a temporary suprarenal IVC filter is an additional and feasible procedure that can prevent immediate and perioperative PE.     

血管平滑肌瘤病影像学评估

目的 探讨血管平滑肌瘤病的影像学表现.资料与方法 分析6例手术病理证实的血管平滑肌瘤病的影像学表现.结果 5例肿瘤起自子宫端,1例局限在下腔静脉内.3例经下腔静脉延伸到右心房,其中1例经右心房到右心室.6例CT显示下腔静脉和/或卵巢静脉扩张,1例左肾静脉扩张.增强后表现为血管内和右心腔内充盈缺损,呈"血管内血管"征;肿瘤自身可呈不均匀强化.2例MRI显示腔静脉扩张,流空效应消失.结论 CT和MRI能提示血管平滑肌瘤病.     

CT features of abdominal manifestations of primary antiphospholipid syndrome.

PURPOSE: The purpose of this work was to evaluate the CT features of the abdominal manifestations of primary antiphospholipid syndrome (PAPS). METHOD: Of the 32 patients who were confirmed to have PAPS among 751 patients with elevated antiphospholipid antibodies during a 2 year period, we retrospectively reviewed the 14 patients who underwent abdominal CT. The clinical indications for abdominal CT included abdominal pain, abdominal distension, or lower leg swelling. CT findings were analyzed with regard to the abdominal vascular system and abdominal organ involvement patterns as well as ancillary findings. RESULTS: Of the 14 patients with PAPS, 10 had involvement of the venous system (72%), 2 of the arterial system (14%), and 2 of both systems (14%). Of the 12 patients who had venous system involvement, 4 had thrombosis in the inferior vena cava (IVC), 2 in both the IVC and the hepatic vein, 1 in the IVC and splenic and portal veins, 1 in the IVC and hepatic and adrenal veins, 1 in the hepatic, portal, and renal veins, and 3 in the portal and superior mesenteric veins. Budd-Chiari syndrome developed in five of the nine patients who had thrombosis of the IVC or hepatic vein. Arterial thrombosis was noted in four patients, hepatic artery in two, aorta in one, renal artery in one, pancreatic arcade in one, and splenic artery in one, with infarct of multiple organs including the liver, jejunum, colon, kidney, and adrenal gland. Seven of the 14 patients (50%) manifested thrombosis or infarct of multiple extra-abdominal organs. CONCLUSION: PAPS should be included in the differential diagnosis when CT demonstrates infarcts in multiple organs or patients have recurrent episodes of venous or arterial thrombosis.     

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.     

The Value of Preprocedure Computed Tomography for Planning Insertion of Inferior Vena Cava Filters

Purpose

To determine if valuable information could be obtained from abdominal computed tomography (CT) performed before insertion of an inferior vena cava (IVC) filter.

Materials and Methods

A retrospective review was performed on IVC filter insertions with a CT performed before the procedure. Cavagram and CT were compared for renal vein and IVC anatomy, the diameter of the IVC, and the prevalence of iliocaval thrombus. Correlations were assessed among 3 reference standards for measuring the IVC at cavography.

Results

The mean IVC diameter was 23.0 mm on CT. On cavagram the mean IVC diameter was assessed by using 3 reference standards: 20.7 mm, with the catheter tip as a reference; 26.9 mm, with a radiopaque ruler; and 23.4 mm, by using a lumbar vertebral body. There was good correlation among the 3 measures of IVC diameter (Pearson's r = 0.75, P < .0001) but moderate correlation with CT (r = 0.36–0.56, P < .001). The sensitivity of cavagram for detecting retroaortic and circumaortic renal veins was 40% and 0%, respectively. Nineteen accessory renal veins (12.8%) were not seen by cavagram. Thirteen patients (8.8%) had iliocaval thrombus on cavagram, of which 12 (92.3%) were not previously detected by CT.

Conclusions

CT is more sensitive than cavagram for detection of renal vein variants and the level of the lowest renal vein. Therefore, if available, the CT should be reviewed before placement of an IVC filter to optimize positioning. Cavagram remains the criterion standard for detection of iliocaval thrombosis and is necessary before IVC filter insertion.     

Renal vein to portal vein collaterals in three cases of renal cell carcinoma extending into the inferior vena cava: Consequences for chemoembolization

Three patients with renal vein and inferior vena cava (IVC) tumor thrombus from left renal cell carcinoma (RCC) showed Lipiodol deposits in the liver following selective SMANCS (styrene maleic acid neocarzinostatin)/Lipiodol embolization of the renal tumors. In 2 of the 3 patients, renal-portal communications were demonstrated during selective renal arteriography. In I of these patients, considerable liver dysfunction occurred after the second renal chemoembolization and Lipiodol deposits persisted in the liver for about 1 month. We conclude that these anastomoses need to be considered prior to embolization therapy of patients with RCC and tumor thrombus in the renal vein and IVC. Sclerosing substances or larger particles may be better embolic agents in such patients.     

左位下腔静脉的MSCT表现及临床意义

目的 探讨左位下腔静脉的多层螺旋CT(multi-slice spiral CT,MSCT)表现及临床意义.方法 选取腹部MSCT多期增强扫描发现的11例左位下腔静脉患者,结合文献讨论其影像学表现.结果 11例左位下腔静脉MSCT表现为3种类型.Ⅰ型1例(9.09％),表现为右侧下腔静脉缺失,左右髂总静脉于第5腰椎左前...     

Suprarenal inferior vena cava filters: a 20-year single-center experience

PURPOSE: To assess the clinical safety and efficacy of suprarenal inferior vena cava (IVC) filters during long-term follow-up. MATERIALS AND METHODS: In this retrospective study, the authors collected the following data about patients who underwent suprarenal IVC filter placement at their institution between 1988 and 2007: demographics, clinical presentation, indications for filter placement, reasons for placing the filter in the suprarenal IVC, type of filter, frequency of pulmonary embolism (PE) after filter placement, and filter-related problems during follow-up. RESULTS: Seventy patients (32 male and 38 female patients; mean age, 60 years) had suprarenal IVC filters. Sixty-two patients presented with symptoms of venous thromboembolism (VTE) and eight had incidental asymptomatic VTE at imaging. Indications for filter placement were as follows: contraindication to anticoagulation (n = 48), complications and/or failure of anticoagulation (n = 12), added protection (n = 8), and prophylaxis (n = 2). Suprarenal placement was chosen due to IVC thrombus (n = 41), intrinsic and/or extrinsic narrowing of the infrarenal IVC (n = 9), renal and/or gonadal vein thrombus (n = 3), congenital IVC anomalies (n = 6), pelvic mass (n = 5), pregnancy (n = 3), and other reasons (n = 3). The following filters were used: Greenfield (n = 29), Simon Nitinol (n = 5), Vena-Tech (n = 3), TrapEase (n = 22), OptEase (n = 3), Tulip (n = 6), Bird's Nest (n = 1), and Recovery (n = 1). During follow-up (mean, 573 days +/- 953), postfilter PE was suspected in 10 patients; eight patients underwent computed tomography (CT), one of whom had PE at CT. None developed new symptoms of caval thrombosis. Abdominal CT (performed in 30 patients at a mean of 543 days +/- 768) showed thrombus in the filter in three patients, fracture in one patient, and penetration of the IVC wall in two patients. CONCLUSIONS: Suprarenal filters are safe and effective in preventing PE. The placement of IVC filters above the renal veins does not carry an added risk of complications.     

Development of thrombus in the major systemic and portal veins after balloon-occluded retrograde transvenous obliteration for treating gastric variceal bleeding: its frequency and outcome evaluation with CT

PURPOSE: To investigate the frequency and outcome of the thrombus that developed in the major systemic and portal veins after balloon-occluded retrograde transvenous obliteration (BRTO) by comparing the computed tomographic (CT) scans obtained before and after BRTO treatment. MATERIALS AND METHODS: Sixty patients with liver cirrhosis who underwent BRTO to treat gastric variceal bleeding were included in this study. The pre- and postprocedural CT scans in these patients were retrospectively compared to evaluate thrombus development in the major systemic and portal veins after BRTO. Thrombus was classified as having a high attenuation (ie, containing iodized oil), combined attenuation, or low attenuation. The outcome of the thrombus that developed in those veins after BRTO was evaluated by reviewing the serial follow-up CT scans. RESULTS: After BRTO, 14 thrombi developed in 13 systemic and portal veins of nine of the 60 patients (15%). Eleven of the 14 thrombi had high attenuation, two thrombi had low attenuation, and one thrombus had a combined attenuation. The 13 affected veins included six splenic veins, four left renal veins, and three main portal veins. On the serial follow-up CT scans (range of the follow-up period, 5-25 months), all 11 high-attenuation thrombi were completely resolved without sequelae in the affected veins. One of the two low-attenuation thrombi disappeared with severe slitlike collapse of the affected left renal vein; the other low-attenuation thrombus had progressed and it caused complete occlusion of the affected main portal vein. One thrombus with a combined attenuation was almost completely resolved without sequelae in the affected splenic vein, despite the transient enlargement of the low-attenuation component. CONCLUSIONS: In this study, the frequency of thrombus development in the major systemic and portal veins after BRTO was 15%. Although iodized oil deposited in those veins appears to be of no great importance, the low-attenuation thrombus can be associated with occlusion of the affected vein. These tendencies, however, require validation in a larger series.     

MRI of the renal veins: assessment of nonneoplastic venous thrombosis.

Nonneoplastic renal vein thrombosis (RVT) is a clinical dilemma that poses a problem both from a clinical and diagnostic imaging perspective. An accurate noninvasive study to diagnose nonneoplastic RVT would be desirable. Magnetic resonance flow imaging is a noninvasive method of assessing vascular patency and depiction of thrombus. Its use for detection of nonneoplastic RVT is reviewed and our experience illustrated. We reviewed retrospectively the MRI studies in 41 patients evaluated for RVT and correlated them with other imaging studies where possible. Twenty patients had either ultrasound or venography. There were no correlative imaging studies done in 21 patients, 19 of whom had normal MRI, with normal clinical follow-up. In others there was good agreement between MRI and ultrasound in 16 of 19 cases. There were five patients with renal venography, of which the MRI agreed with the results in 3 of 5. Magnetic resonance imaging offers a noninvasive approach to the difficult diagnostic dilemma of RVT.     

下腔静脉病变的螺旋CT诊断

目的 探讨下腔静脉病变的螺旋CT及下腔静脉CT血管造影（CTP）的影像特点。资料与方法 40例肿瘤侵犯下腔静脉及下腔静脉病变，采用螺旋CT平扫、增强扫描及下腔静脉CTP检查，分析不同扫描模式及后处理图像所示病变的部位、范围、密度变化特点及侧支循环形成。结果 19例肝癌沿肝静脉侵犯下腔静脉，癌栓位于下腔静脉肝段及肝上段；邻近下腔静脉肝段的肝癌直接侵犯下腔静脉；6例轻度强化，未见明显侧支循环形成。9例肾癌沿肾静脉侵犯下腔静脉，癌栓位于肾上段，无强化，见肾包膜静脉侧支形成及性腺静脉增粗。5例下腔静脉血栓管腔狭窄或闭塞，呈节段性，壁不光整，可见条状或斑点状钙化，CTP后延迟扫描，病变段无明显强化，见明显的侧支循环。3例下腔静脉内血管平滑肌瘤病，起自子宫，沿卵巢静脉及髂静脉上行，经下腔静脉侵入右心房，病变密度较均匀，无钙化及坏死囊变，强化较明显，病变段附近见大量侧支循环形成。发育异常所致布一加综合征（Budd-Chiari syndrome）3例，表现为肝上段节段性狭窄，周围见大量的侧支循环形成。下腔静脉内平滑肌肉瘤1例，病变位于肝下段下腔静脉，呈节段性增粗，边缘不光整，密度不均，延迟CT扫描后不均匀强化，邻近见大量侧支循环形成。结论 下腔静脉病变的CT表现以充盈缺损、无或轻-中度强化、管腔狭窄及侧支血管形成为特征，下腔静脉CTP的三维重建能立体显示管腔狭窄和侧支血管，合理的CT扫描模式有利于病变的诊断和确定手术方案。     

Puerperal ovarian vein thrombosis: evaluation with CT, US, and MR imaging

Five women suspected of having puerperal ovarian vein thrombosis (POVT) were examined with either computed tomography (CT) (five patients), ultrasonography (US) (three patients), magnetic resonance (MR) imaging (one patient), or a combination of these modalities. CT findings included tubular retroperitoneal mass (five patients), periuterine mass (four patients), enlarged uterus (four patients), fluid in the uterus (five patients), central ovarian vein thrombus (four patients), inferior vena cava thrombus (one patient), right hydroureter (one patient), and right ureteral compression (one patient). US findings were similar to CT findings except for an inability to demonstrate the right hydroureter and ureteral compression. MR imaging demonstrated the retroperitoneal mass and central ovarian vein thrombus. CT proved to be superior for the initial evaluation and subsequent diagnosis of POVT. US was useful for follow-up examinations, and MR imaging results confirmed a case of POVT that was suspected following CT.     

膜性肾病并发肾静脉血栓的彩色多普勒超声表现分析

目的探讨膜性肾病患者并发肾静脉血栓的彩色多普勒超声表现及其临床意义。方法膜性肾病27例,用二维超声和彩色多普勒超声观察肾脏的大小、形态、内部回声及肾静脉内是否有血栓。结果 27例中左肾主静脉血栓形成6例,段支1例,右肾主静脉血栓形成3例,段支1例,双肾主静脉血栓形成1例,本组27例膜性肾病患者并发肾静脉血栓的发生率为44%。结论彩色多普勒超声可作为诊断肾静脉血栓的首选方法。     

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.     

Techniques of adrenal venous sampling in patients with inferior vena cava or renal vein anomalies

Purpose

To review the techniques and technical success rate of adrenal venous sampling (AVS) in patients with inferior vena cava (IVC) or renal vein anomalies.

Materials and methods

The techniques and success rate of AVS in 15 patients with anomalies [8 with double IVC (dIVC), 3 with left IVC (ltIVC), 2 with retroaortic left renal vein (LRV), and 2 with circumaortic LRV] underwent AVS was retrospectively reviewed.

Results

Among 11 patients with IVC anomalies, the success rates for sampling the right and left adrenal veins (RAV and LAV) were 81.8 and 90.9%, respectively. In dIVC, the LAV was selected using the following four methods: approaching through the right IVC from the right femoral vein, flipping the LAV catheter tip in the LRV (n?=?4) or the interiliac-communicating vein (n?=?1), or through the ltIVC from the right (n?=?1) or left (n?=?2) femoral vein. Among the four patients with LRV anomalies, the success rate was 100% for each adrenal vein.

Conclusion

AVS can be successfully performed in patients with anomalies. The key to technical success is understanding the venous anatomy based on pre-procedural CT images and choosing appropriate methods.

     

肺肾双能量CTA筛查肾病综合征患者静脉血栓栓塞的发生率

目的：利用CT筛查肾病综合征患者静脉血栓栓塞事件的发生率及其临床意义。方法：2010年5月-2012年8月974例患者行双能量CT肺动脉成像（CTPA）,其中451例肾病综合征患者（包括66例儿童）进行了肺肾联合双能量CT扫描以筛查肺栓塞和肾静脉栓塞。153例患者同时进行了下肢超声检查用于筛查深静脉血栓。记录肺栓塞、肾静脉栓塞、下肢深静脉血栓的发生率及其相互关系。结果：177（39．2％）例患者至少有一个静脉血栓栓塞事件,其中以肺栓塞最常见（149／177,84．1％）,76例肺栓塞患者合并肾静脉栓塞,孤立性肺栓塞54例。大多数肺栓塞患者（118／149,79．2％）无临床症状。106例（106／451,23．5％）例患者有肾静脉栓塞,26例（26／153,17．0％）患者有深静脉栓塞。儿童患者静脉血栓事件发生率（13／66,19．7％）低于成人（164／385,42．6％）。在组织学证实的肾病类型中,膜性肾病最常伴有静脉血栓事件（72／153,47．1％）。结论：肺栓塞是肾病综合征患者最常见的血栓并发症且大多是无症状的,常伴有肾静脉血栓或孤立发生,因此对本病的可疑静脉血栓患者的筛查是需要的。