Colour Doppler ultrasound in deep venous thrombosis: a comparison with venography

Colour Doppler ultrasound is a new technical development allowing simultaneous grey scale imaging and a dynamic colour flow vascular image. To date, many real time ultrasonic studies have been assessed in the diagnosis of lower limb venous thrombosis and have been shown to be accurate in the femoral and popliteal segments. A double blind prospective study comparing colour Doppler with contrast venography in the diagnosis of lower limb thrombosis was performed in a group of 40 patients. Of the study group, 26 venograms were negative and 27 ultrasound examinations were negative. Of the 14 positive venograms there was one false negative colour doppler scan which missed a calf and lower popliteal thrombosis. Two cases of isolated calf vein thrombosis were successfully detected by colour Doppler. Overall, the sensitivity and specificity for detection of lower limb venous thrombosis, including calf vein assessment, were 93% and 100% respectively. Colour Doppler is easy to perform; the average scanning time being 15 minutes for complete assessment of a unilateral lower limb venous system. Spontaneous flow is evident in the femoropopliteal segment, whilst proximal calf vein flow can only be appreciated with the aid of distal compression. Eccentric thrombus and partially recanalized thrombus can be shown. Although the number of isolated calf vein thromboses was small, early experience suggests colour Doppler may be useful in the assessment of proximal calf vein patency.     

<Superscript>18</Superscript>F FDG PET/CT demonstration of IVC and right atrial involvement in adrenocortical carcinoma

Adrenocortical carcinoma is a rare and aggressive tumour. Inferior vena caval (IVC) involvement by the tumour thrombus is a rare phenomenon, and extension into the right atrium is even more rare. We describe a patient with Cushing’s syndrome for whom ¹⁸F-fluorodeoxyglucose (FDG) PET/CT showed FDG avid right adrenal mass with tumour extension to the IVC and right atrium.     

Obstruction of the inferior vena cava: a multiple-modality demonstration of causes, manifestations, and collateral pathways.

This article explores the causes and manifestations of obstruction of the inferior vena cava (IVC) with a multiple-modality approach. Caval obstruction may be due to thrombus, extension of a tumor, extrinsic compression, or intrinsic caval disease. Evaluation of the IVC should be tailored to the individual circumstance; no single modality is best in all situations. Although magnetic resonance offers multiplanar imaging, vena cavography or ultrasound are often necessary to exclude intraluminal tumor extension. Computed tomography is sensitive for intracaval thrombus and compression but does not delineate the hepatic IVC well. Nuclear venography demonstrates well the resultant collateral pathways, which can be separated into the deep, intermediate, superficial, and portal systems. Despite the clear visualization of these pathways with this modality, congenital caval anomalies, such as caval interruption with azygos continuation, can be confused with acquired caval disease.     

彩色多普勒超声诊断肝移植术后下腔静脉栓塞及狭窄

目的:探讨彩色多普勒超声诊断肝移植术后下腔静脉栓塞及狭窄的价值.材料和方法:回顾性分析103例成人肝移植术后9例下腔静脉栓塞及狭窄的彩色多普勒超声表现.结果:超声发现下腔静脉栓塞7例,下腔静脉狭窄2例,均经血管造影、磁共振或临床证实.下腔静脉栓塞超声表现为吻合口及下腔静脉内部分或完全被等回声充填,彩色多普勒及频谱多普勒显示充填部分血流信号消失;下腔静脉狭窄的超声表现为吻合口血流紊乱且血流速度加快.结论:多普勒超声在肝移植术后下静脉栓塞及狭窄的诊断中具有重要的价值.     

Ultrasound and MR imaging of diabetic mastopathy

AIM: To review the imaging findings of diabetic mastopathy, and document the colour flow ultrasound and MR imaging features in this benign condition. MATERIALS AND METHODS: Diabetic mastopathy was clinically and histologically diagnosed in eight lesions in six women. All six women underwent conventional mammography and high frequency grey-scale ultrasound. Colour flow ultrasound was performed additionally in six lesions in four women and MR imaging in four lesions in three women before biopsy. The imaging findings were reviewed and correlated with final histological diagnosis. RESULTS: Mammography showed regional asymmetric increased opacity with ill-defined margins in all lesions. A heterogeneously hypoechoic mass with ill-defined margins was identified on high frequency grey-scale ultrasound in all lesions. Marked posterior acoustic shadowing was present in seven of eight (88%) lesions. Six lesions interrogated with colour flow ultrasound showed absence of Doppler signal. MR imaging in three women revealed non-specific stromal enhancement. CONCLUSION: Diabetic mastopathy shows absence of Doppler signal on colour flow ultrasound and non-specific stromal enhancement on MR imaging.     

Clinical use of Levovist, an ultrasound contrast agent, in the imaging of liver transplantation: assessment of the pre- and post-transplant patient

Colour Doppler US is well established for imaging of hepatic vessels in the assessment of pre- and post-liver transplant patients. Unfortunately, a full colour Doppler US examination of the portal or hepatic venous and hepatic arterial systems is frequently precluded by technical factors. Ultrasound contrast agents are useful in enhancing vascular Doppler signal and play an important role in liver transplantation assessment. A series of patients with vascular problems illustrates the role of US contrast in the pre-transplant candidate, where portal vein patency and direction of flow is assessed, presence of portal vein thrombus is confirmed and cavernous transformation demonstrated. Occlusion of hepatic veins in Budd-Chiari syndrome is confidently confirmed. Following liver transplantation, US contrast allows a comprehensive assessment of hepatic artery thrombosis, hepatic artery stenosis and pseudoaneurysm formation. The need for further imaging is reduced or confidently deferred in many instances. Ultrasound contrast agents play an important role in the liver transplant candidate. Received: 15 April 1999; Revised: 21 June 1999; Accepted: 22 June 1999     

Three-Dimensional Rotational Angiography of the Inferior Vena Cava as an Adjunct to Inferior Vena Cava Filter Retrieval

The objective of this study was to explore the role of three-dimensional (3-D) rotational angiography (RA) of the inferior vena cava (IVC; 3-D CV) before filter retrieval and its impact on treatment planning compared with standard anteroposterior cavography (sCV). Thirty patients underwent sCV and 3-D CV before IVC filter retrieval. Parameters assessed were: projection of filter arms or legs beyond the caval lumen, thrombus burden within the filter and IVC, and orientation of the filter within IVC. Skin and effective radiation doses were calculated. Statistical analysis was performed using paired Student t test and nonparametric McNemar’s test. Standard anteroposterior cavography detected 49 filter arms or legs projecting beyond the caval lumen in 25 patients. Three-dimensional CV demonstrated 89 filter arms or legs projecting beyond the caval lumen in 28 patients. Twenty-two patients had additional filter arms or legs projecting beyond the caval lumen detected on 3-D CV that were not detected on sCV (p < 0.001). Filter apex tilt detection differed significantly (p < 0.001) between sCV and 3-D CV, with 3-D CV being more accurate. The filter apex abutted the IVC wall in 10 patients (33%) on 3-D CV, but this was diagnosed in only 3 patients (10%) with sCV. Thrombus was detected in 8 patients (27%), 1 thrombus of which was seen only on 3-D CV, and treatment was changed in this patient because of thrombus size. Mean effective radiation doses for 3-D CV were approximately two times higher than for sCV (1.68 vs. 0.86 mSv), whereas skin doses were three times lower (12.87 vs. 35.86 mGy). Compared with sCV, performing 3-D CV before optional IVC filter retrieval has the potential to improve assessment of filter arms or legs projecting beyond the caval lumen, filter orientation, and thrombus burden.     

Diagnosis and follow-up of children with Wilms' tumor: correlative study of ultrasound and computed tomography. Report of eighteen cases.

A retrospective study of 18 children with Wilms' tumor was performed to compare the efficacy of ultrasound (US) and computed tomography (CT) for the diagnosis, staging, and follow-up evaluation of these patients. US and CT were found to be complementary to one another in evaluation of Wilms' tumor. In one patient, CT was more accurate than US in determining the organ of origin of a very large tumor. US is superior to CT for the evaluation of thrombosis in IVC. It can define whether or not the thrombus is attached to the wall of the IVC. This finding has a major impact on the management of the patient.     

Prevalence of local venous thrombosis after transfemoral placement of a Bird's Nest vena caval filter

Bird's Nest vena caval filters were placed in 63 patients over a 6-month period by means of a transfemoral (n = 62) or transjugular (n = 1) approach. To determine the prevalence of access-site thrombosis, compression color Doppler flow imaging was performed 1-11 days after the procedure in 48 patients without suspected or documented preexisting thrombus. Clinical follow-up was from 5 to 289 days (mean, 100 days). Findings at ultrasound (US) examination were normal in 38 patients, and all of these patients remained clinically asymptomatic. Nonocclusive thrombus was seen in nine patients, eight of whom remained asymptomatic. A single patient had an occlusive thrombus at US. This patient had leg swelling. Nonocclusive thrombus did not predispose patients to the development of clinically evident occlusive thrombosis. The authors conclude that the transfemoral placement of the Bird's Nest vena caval filter is associated with a low prevalence (2%) of femoral vein occlusion documented at US follow-up. This contrasts with results from a similarly designed study demonstrating a 17% prevalence after percutaneous Greenfield filter placement.     

Accuracy of diagnostic imaging in nephroblastoma before preoperative chemotherapy

The main strategy in the treatment of nephroblastoma, as described in protocol SIOP 9/GPO, is preoperative chemotherapy for patients between 6 months and 16 years of age. Before treatment the diagnosis is made only by diagnostic imaging without biopsy. From July 1988 to February 1991, 130 children with the tentative diagnosis of nephroblastoma were treated preoperatively. The initial diagnostic images (excretory urography, ultrasound, CT, MRI) have been analysed both prospectively and retrosperatively and the findings correlated with the intraoperative and histological results. Of the preoperatively treated patients 93.8% had a Wilms' tumour or one of its variants. Five patients had a different malignant tumour and 3 patients, i.e. 2.3% of those preoperatively treated or 1.6% of all registered patients, had benign tumours of the kidney. Wilms' tumour generally presented as a well-defined mass with an inhomogeneous morphology on CT. On ultrasound only 24% of the tumours were homogeneous. Intratumoral haemorrhage and cystic areas occurred frequently; calcifications were rare (8%). With regard to caval involvement only ultrasound and MRI enabled the correct diagnosis, while CT could not differentiate compressions from invasion. The pretherapeutic diagnostic imaging was of sufficient accuracy to start preoperative chemotherapy without diagnostic biopsy.Correspondence to: K. Rieden     

Preliminary results of colour Doppler-guided intratendinous glucocorticoid injection for Achilles tendonitis in five patients

BACKGROUND: It is debated as to whether Achilles tendonitis (AT) has an inflammatory component. The intratendinous hyperaemia demonstrated with colour Doppler has been interpreted as neovascularisation. Glucocorticoid injection around the tendon is a common therapeutic procedure. HYPOTHESES: The intratendinous hyperaemia seen with ultrasound (US) colour Doppler represents an inflammatory background. Glucocorticoid injections will be effective if administered inside the tendon where the inflammation seems to be. STUDY DESIGN: An uncontrolled, prospective study with a minimum follow-up of 3 months. METHODS: Six tendons in five patients were evaluated with grey-scale US and colour Doppler before and after US-guided intratendinous glucocorticoid injection. Pain at rest and at activity was evaluated on a visual analogue scale. RESULTS: With colour Doppler all tendons had intratendinous flow. Pain and colour Doppler activity decreased during a mean follow-up of 182 days (range 92-309 days). One tendon relapsed after 199 days. CONCLUSION: Intratendinous glucocorticoid injections seem to have a marked effect on both symptoms and colour Doppler findings, which may be taken as an indication of an inflammatory component in the disease. Colour Doppler adds significant information to grey-scale US with regard to diagnosis, location and follow-up of AT.     

The role of colour flow Doppler in the investigation of the salivary gland tumour

AIMS: Ultrasound is a highly effective imaging technique to determine salivary gland tumours and may help to identify many benign lesions. The aim of this study is to evaluate whether colour Doppler is able to further differentiate the malignant tumour. METHODS: Fifty-six patients with salivary gland lesions were prospectively assessed using ultrasound imaging with colour flow and power Doppler. The peak systolic velocity (PSV) was measured and the pulsatility index (PI) and resistive index (RI) calculations were performed on the pulsed wave traces. The real time ultrasound morphology and the Doppler information were correlated with the histology. RESULTS: In 18 of the 56 patients, no internal colour flow or power Doppler changes could be detected. The real time ultrasound morphology diagnosed benign disease with sensitivity of 89.7% with specificity of 57.1%. The positive predictive value was 93.6%. There were no significant differences in the colour Doppler appearances in terms of vessel type or intratumour distribution which could separate benign from malignant conditions. However, there was statistical discrimination for PI and RI values (P = 0.0006, P = 0.0002, respectively). No malignant lesions were seen when the PI was less than 1.8 and RI was less than 0.8. The PSV was elevated in several cases (> 50 cm per s) but there was no statistical correlation with malignancy. CONCLUSION: The risk of malignancy increases by a third when the colour Doppler demonstrates increased intratumour vascular resistance (RI > 0.8 and PI > 1.8), with positive predictive value of 97.3% (sensitivity 75.5%, specificity 85.7%).Bradley, M. J. (2000). Clinical Radiology55, 759-762.     

With advances in medical imaging can the radiologist reliably diagnose Wilms' tumours?

AIM: To evaluate whether radiologists can accurately differentiate Wilms' tumours from other paediatric abdominal masses with renal involvement using modern imaging methods alone. METHODS: From February 1993 to June 1997, 23 patients presented to the Paediatric Oncology Service at The Royal Hospital for Sick Children, Edinburgh with an intra-abdominal mass which had renal involvement. Nine patients had Wilms' tumours, 12 had neuroblastomas, one patient had xanthogranulomatous pyelonephritis and there was a single case of a mesoblastic nephroma. In each case, two radiologists retrospectively reviewed the initial imaging examinations and independently reached a radiological diagnosis. RESULTS: The radiologists were concordant and reached the correct diagnosis in 20/23 cases (87%), unsure of the diagnosis in one case (4.3 %) and discordant in two cases (8.7 %). Radiologists should be aware that a mesoblastic nephroma can have identical imaging features to a Wilms' tumour. In most cases, ultrasound and a chest X-ray were sufficient to reach the correct diagnosis although computed tomography (CT) and magnetic resonance imaging were superior for demonstrating the relationship of the mass to the great vessels, retroperitoneum and spinal canal. Inferior vena cava invasion was strongly predictive of a Wilms' tumour. Displacement of the great vessels, extension of the mass across the mid-line, renal displacement and tumour calcification on CT were more suggestive of a neuroblastoma although these features were also seen in a significant number of patients with Wilms' tumours. Encasement of vessels by tumour, a paravertebral mass and spinal canal invasion were highly predictive of neuroblastoma. CONCLUSION: In this study, radiologists were accurate at diagnosing Wilms' tumours using modern imaging methods, however, care should be taken in children who are less than 1 year of age as a mesoblastic nephroma may have identical imaging characteristics.     

Inferior vena caval filter thrombi: evaluation with intravascular US

A 20-MHz intravascular ultrasound (US) transducer inside a percutaneously inserted catheter was used to evaluate inferior vena caval (IVC) filters for thrombi in vitro and in vivo. Six different IVC filters were studied with intravascular US in a saline-filled model. Each filter had a characteristic, recognizable US pattern. Experimental thrombi as small as 0.5 cm3 were easily detected. Intravascular US was used clinically 25 times to evaluate the IVC in 23 patients with 24 IVC filters. Positive-contrast cavograms were available for comparison in all 25 cases. In 13 cases, no thrombi were identified in the filter or IVC with either intravascular US or cavography; in five of 12 cases with thrombi, intravascular US and cavography demonstrated the thrombi equally well. In six cases, intravascular US was superior to cavography in detection or delineation of thrombus in the IVC or filter. Intravascular US was considered superior to external duplex US in evaluation of caval thrombi in all 21 cases available for comparison. No complications from intravascular US were noted.     

Does Doppler analysis of musculoskeletal soft-tissue tumours help predict tumour malignancy?

AIM: To investigate whether analysing vascularity of soft-tissue tumours on ultrasound assists differentiating benign from malignant tumours. MATERIALS AND METHODS: One hundred and forty-eight vascular soft-tissue tumours in 148 patients (88 males, mean age 45.6 years) were studied. Final diagnosis was established histologically in 95 (64%) of cases. For each tumour, three-colour Doppler imaging features (vascularity, vascular density, vascular organization) and 13 pulsed Doppler (spectral analysis) parameters were assessed. Data analysis was performed to isolate optimal discriminatory criteria for differentiating benign from malignant tumours. RESULTS: Significantly more benign soft-tissue tumours had an organized vascular pattern on colour Doppler imaging. If the vascular pattern is organized, this is a good indicator of tumour benignity. However, this pattern was apparent in less then one-third of the soft-tissue tumours. Benign tumours also had significantly higher minimum end diastolic velocity (EDVmin) and lower mean ratio of resistive index (RImean) than malignant soft-tissue tumours, though considerable overlap existed between the two groups. CONCLUSION: Colour Doppler imaging analysis of soft-tissue tumours is of limited value when differentiating benign from malignant tumours. If an organized vascular pattern is present, the tumour is more likely to be benign. Flow characteristics were not specific enough to be applicable in clinical practice.     

Budd-Chiari syndrome: value of duplex sonography and colour Doppler imaging for diagnosis and follow-up

This retrospective study was designed to evaluate duplex sonography in the diagnosis and follow-up of patients with Budd-Chiari syndrome. Thirteen patients with clotting disease and histologically proven Budd-Chiari syndrome (3 acute and 10 chronic cases) were examined, using conventional duplex sonography (n=5) or colour-coded duplex sonography (n=8). Results were compared with CT in 6 cases, MRI in 11, coeliac and mesentric angiography in 5, and hepatic wedge venography and cavography in 6. Of 39 hepatic veins examined, 33 had an abnormal appearance on ultrasound studies: endoluminal thrombus, stenosis, dilatation, thick wall echoes. Doppler findings included total obstruction of 8 hepatic veins, reversed flow in 22 hepatic veins and intrahepatic collaterals with continous non-phasic flow in all cases. Duplex sonography showed portal thrombosis (n=1), evidence of portal hypertension (n=8) and inferior vena cava thrombosis (n=2). Nine patients were treated surgically. Patency of portocaval shunts was correctly assessed with colour coded duplex sonography in 8 of 9 patients. We believe that colour Doppler imaging is the procedure of choice for initial diagnosis of Budd-Chiari syndrome. Correspondence to: M. F. Bellin     

肝静脉阻塞型布-加氏综合征的超声诊断价值

目的:探索彩色多普勒超声对肝静脉阻塞型布-加氏综合征的诊断价值.材料和方法:应用彩色多普勒超声观察138例肝静脉阻塞型布-加氏综合征的彩色多普勒超声的声像图特点, 并与血管造影对比分析. 结果:肝静脉隔膜型阻塞83 例(60.1 %),节段性闭塞45 例(32.6 %),单纯狭窄10例(7.3 %).表现为肝静脉流出道有狭窄、闭锁、栓子或隔膜梗阻图像,肝静脉间可见交通支形成,肝短静脉代偿性扩张,第三肝门开放等.同时存在肝静脉和下腔静脉阻塞者35例,合并下腔静脉血栓者11例,肝静脉血栓7例.超声诊断假阳性2例,假阴性3例.结论:彩色多普勒超声可较准确地判定肝静脉血管狭窄及闭塞的部位和类型,并明确血管梗阻的程度及侧支血管形成情况,有助于手术方式的选择以及术后疗效的判断.     

Prototype percutaneous thrombolytic device: preclinical testing in subacute inferior vena caval thrombosis in a pig model.

PURPOSE: To develop an animal model of subacute inferior vena caval (IVC) thrombosis and apply this model in evaluating the safety and efficacy of a prototype percutaneous thrombolytic device for restoring patency. MATERIALS AND METHODS: In 11 pigs, a stent with a ligature in the middle was placed in the IVC. Thrombin was injected to induce thrombosis. Hemostasis was achieved by using an occlusion balloon. The stent was ligated to prevent thrombus migration. Five to 8 days after thrombus induction, the ligature was broken and the stent fully deployed. In 10 animals, thrombectomy was performed by using the percutaneous thrombolytic device. A vena caval filter was inserted at the beginning of each declotting procedure. Thrombus removal percentage was estimated and pulmonary angiograms obtained to detect embolism before and after thrombectomy. The IVC was analyzed histologically. To determine thrombus composition, one animal was sacrificed without thrombectomy. Concerning procedural safety, failure of the stent delivery system, stent migration, and venous perforation due to balloon inflation and the stent placement or thrombectomy procedure were evaluated. RESULTS: Thrombus creation was successful in all animals. Fragmentation led to 75%--100% thrombus removal with flow restoration in all cases. There were no episodes of stent delivery failure, stent migration, or venous perforation. No significant pulmonary embolism was observed. In one case, a vessel dissection was identified at histologic examination. CONCLUSION: In this animal model of IVC thrombosis, the percutaneous thrombolytic device is effective and safe for clot removal.     

Activity of Crohn's disease assessed by colour Doppler ultrasound analysis of the affected loops

The aim of this study was to evaluate with colour Doppler ultrasound the vascular changes in the wall of the loops affected by Crohn's disease, and to establish whether these changes reflects clinical or biochemical activity of Crohn's disease. Seventy-nine patients with Crohn's disease (44 with active disease and 35 inactive patients) were studied with frequency- and amplitude-encoded duplex Doppler sonography. A group of 35 healthy volunteers were also included. The exam consisted of the search for colour signals in the walls of the loops affected by Crohn's disease, classifying the degree of vascularity with a simple scoring system into three groups: absence of colour signal (score of 0); weak or scattered colour signals (score of 1); and multiple colour signals or clear identification of vessels in the loops walls (score of 2). Doppler curves were obtained of the detected vessels with measurement of the resistive index (RI). There was a visible increase in the gut walls' vascularity in the active patients compared with those with inactive disease. The mean RI was statistically significantly lower in the gut wall vessels of the patients with active illness than that obtained in the inactive patients. Colour Doppler ultrasound is a useful tool in the assessment of activity in Crohn's disease.     

Colour flow imaging of calf vein thrombosis.

Ultrasound and more recently colour Doppler ultrasound has been successfully used in the diagnosis of lower limb venous occlusive disease. Colour Doppler ultrasound has shown promise in the diagnosis of calf vein thrombosis but to date there has been no prospective trial to specifically evaluate its potential. In view of this, we carried out a prospective trial of 50 patients comparing the accuracy of colour Doppler ultrasound with venography in the diagnosis of deep venous thrombosis both above and below knee but in particular with respect to the detection of calf vein clot. Of the 50 patients studied, 10 had only one imaging modality performed as there were eight venographic failures and two ultrasonic failures. Comparison was only thus possible in 40 cases. As in previous studies, colour Doppler ultrasound was shown to be accurate in the diagnosis of thrombosis within the femoro-popliteal veins and had a sensitivity and specificity of 100% respectively. With respect to calf vein lesions, there was one false negative scan using the ultrasonic technique giving a sensitivity of 95%, specificity of 100% and accuracy of 97.5%. We feel colour Doppler ultrasound can and should be used as a first line alternative to venography and can be employed for the exclusion of both above and below knee deep venous thrombosis. Venography should now be reserved for those patients who are unsuitable for ultrasound examination or who have an equivocal ultrasound scan.