Tomography Venography Research Articles

Use of time resolved magnetic resonance imaging in the diagnosis of pelvic congestion syndrome

We describe the efficacy of time-resolved MR angiography in diagnosing a case of pelvic congestion syndrome (PCS). MR angiography, using four-dimensional (4D) TRAK (Time-Resolved Angiography using Keyhole) technique was used in an 81-year-old woman presenting with low backache, pelvic pain, and left pelvic fullness. Dynamic images were obtained in multiple vascular phases including arterial, arteriovenous, and venous phases. The high temporal resolution of 4D TRAK could demonstrate early retrograde left ovarian vein filling as well as multiple dilated pelvic varices, allowing the prospective diagnosis of PCS to be made. Although uncommon in this age group, the diagnosis was subsequently confirmed on conventional catheter venography with symptomatic relief after successful embolization of the incompetent left ovarian vein. The MRA and correlative catheter venography images are presented in this case report.

Occurrence of Post-Acute Recanalization and Collateral Formation in Patients with Cerebral Venous and Sinus Thrombosis. A Serial Venographic Study

The underlying mechanism for symptomatic recovery in patients with cerebral venous and sinus thrombosis (CVST) is not clear, although post-acute recanalization and collateral formation have been proposed as possible mechanisms. To identify the occurrence of recanalization and collateral formation among survivors of CVST and explore its association with symptomatic recovery. We identified all the patients admitted with CVST over a 5-year period and who underwent initial magnetic resonance (MR) or computed tomographic (CT) venography and a follow-up CT or MR venography between 3 and 12 months after onset. All the images were reviewed by a single observer using the classification for recanalization proposed by Qureshi grade I--partial recanalization of one or more occluded dural sinus with improved flow or visualization of branches; grade II--complete recanalization of one sinus but persistent occlusion of the other sinuses [A--no residual flow, B--non occlusive flow]; grade III--complete recanalization and for collateral formation (grade I--collaterals bypass occluded segment of dural venous sinus but connect within the same sinus; grade II--collaterals bypass occluded segment but connect with a different sinus; grade III--collaterals bypass the occluded segment and connect with different circulation). A total of 39 patients with CVST (mean age 34.82 [± 17.1 SD]; 19 were men) had an initial and follow-up venographic study performed. Of these, 21 patients underwent serial venographic imaging using the same modality allowing a direct comparison. Of the 17 patients who had recanalization during follow-up, 10 patients had grade I recanalization, 7 had grade III recanalization, and 4 had no recanalization. Collateral formation was seen in 8 patients: grade I in 3 patients, grade II in 1 patient, and grade III in 4 patients. The proportion of patients with persistent headaches appeared higher in those with no or partial recanalization than with complete recanalization (5 of 14 patients vs. 0 of 7 patients) and in patients with no collaterals than patients with collaterals (4 out of 13 vs. 1 out of 8). None of the patients experienced any recurrence or new symptoms. Complete or partial recanalization and collateral formation are seen in a prominent proportion of patients with CVST in the months following initial diagnosis. Further studies need to identify the temporal course and clinical significance of venographic recanalization and collateral formation, and factors influencing venographic changes.

Bilateral stenting at the iliocaval confluence

This study describes three techniques of stent placement at the iliocaval confluence for chronic nonmalignant obstruction and its stent-related outcome. From 1997 to 2008, 115 patients (230 limbs) underwent bilateral stenting for iliocaval obstruction. All limbs were CEAP classified using clinical examination and duplex ultrasound study. Three techniques were compared: placement of two stents side by side in a "double-barrel" (group DB, n = 39); inverted Y stenting through a fenestra (window) created through the side braiding of a stent placed previously across the iliocaval confluence (group iY, n = 38); apposition of a stent as close as possible to a stent previously placed across the iliocaval confluence, leaving a small area unsupported between the stents (group A, n = 38). Patency was assessed with venography and duplex ultrasound imaging. Cumulative patency curves were calculated. Median age was 54 years (range, 14-76 years); female/male ratio was 2.8:1. Obstructions were primary in 141 limbs and postthrombotic in 89, and 29 required recanalization of occlusions. The C(4-6) rate and ratio of limbs with postthrombotic obstruction were significantly higher in group iY vs group DB (49% and 32% [P = .049]; 47% and 28% [P = .022], respectively). The median follow-up was 12 months (range, 1-108 months) in 107 patients (93%). The overall primary, assisted primary, and secondary patency rates at 4 years were 61%, 92%, and 98%, respectively. The distribution of occluded stent systems (n = 4) and frequency of reinterventions (n = 29) were reflected in the primary and secondary patency rates for groups A, DB, and iY at 4 years (77% and 100%, 73% and 100%, and 41% and 90%, respectively). The frequency of reinterventions was significantly lower in group DB vs groups A and iY (8%, 32%, and 37%, respectively; P < .01). Chronic iliocaval confluence obstruction is best managed by double-barrel stenting when feasible. The apposition technique requires a high reintervention rate owing to restenosis of the unsupported segment. The secondary stent patency appears to be less in limbs with postthrombotic occlusion. Primary stent patency of nonocclusive obstruction was inferior in group iY regardless of etiology of obstruction. However, inverted Y fenestration is the only choice in delayed contralateral stenting or when the inferior vena cava is extensively involved. There is no optimal solution to the treatment of the iliocaval confluence presently, and the choice of technique is decided by the extent, site, and type of obstruction.

Endovascular Management of Congenital Atresia of the Infrarenal IVC

This case illustrates the feasibility of endovascular treatment for chronic venous insufficiency attributable to congenital atresia of the infrarenal inferior vena cava (IVC). Three-dimensional computed tomography (CT) venography can elucidate alternate sites of drainage and identify other venous pathology, such as dominant stenoses that may be amenable to venoplasty and/or stent placement.

Preoperative Mapping for Haemodialysis Access Surgery with CO 2 Venography of the Upper Limb

Objective This study aims to evaluate the impact of CO 2 venography on the planning and outcome of native arteriovenous fistula (AVF) creation. Methods Records of patients who underwent CO 2 venography prior to access surgery between January 2000 and December 2008 were reviewed. CO 2 venography was performed selectively in chronic kidney disease (CKD) in stage IV–V patients without suitable veins on clinical examination. Findings at surgery were compared to CO 2 venography images. Patency of AVFs was analysed by the Kaplan–Meier method. Differences in outcome of maturation were compared using a χ 2 test. Results A total of 209 CO 2 venograms were obtained in 116 patients. In 89 patients (77%), 101 AVFs (21 forearm AVF (21%) and 80 elbow AVF (79%) were created. Surgical findings corresponded with CO 2 venography findings in 90% of patients. In 10 cases (10%), access was created at the elbow despite a patent forearm cephalic vein on CO 2 venography ( n = 2) or access was attempted with a vein which was thought to be unsuitable on CO 2 venography ( n = 8). Maturation rate of the latter was 50% (4/8) vs. 88% (80/91) for AVFs created with veins considered usable ( P = 0.004). The overall maturation rate was 84% with 1-year primary, assisted primary and secondary patency rates of 63%, 70% and 71%, respectively. Conclusion CO 2 venography is a useful tool for venous mapping prior to vascular access surgery, resulting in an overall maturation rate of 84% and good patency rates.

Catheter-Directed Thrombolysis with Conventional Aspiration Thrombectomy for Lower Extremity Deep Vein Thrombosis

PurposeThe purpose of this study is to evaluate treatment outcomes in patients with symptomatic deep vein thrombosis (DVT) who had undergone a catheter-directed thrombolysis with conventional aspiration thrombectomy for the treatment of lower extremity deep vein thrombosis.Materials and MethodsThe authors retrospectively reviewed the records of 74 patients (mean age 61 ± 15) that underwent a catheter-directed thrombolysis with conventional aspiration thrombectomy. A retrieval inferior vena cava (IVC) filter was placed to protect against a pulmonary embolism in 60 patients (81%). Stenting and balloon angioplasty were performed in 37 patients (50%) under the left common iliac vein compression.ResultsSixty-seven patients (91%) showed a clinical improvement within 48 hours, but seven patients (9%) showed no improvement. Multi detector computerized tomographic venography (MDCT venography) at discharge showed no thrombus in 15 patients (20%) and partial thrombus in 52 (70%). Twenty-eight patients (38%) developed post-thrombotic syndrome at 3.0 ± 4.2 months postoperatively. Six patients (8%) were admitted due to DVT recurrence at a mean of 5.6 ± 7.4 months postoperatively. Sixty-nine patients underwent follow up MDCT venography at 5.7 ± 5.6 months. fifty (72%) of these showed no thrombus, 15 (22%) partial thrombus, and 4 (6%) showed obstruction. Twentyeight of 61 (46%) were asymptomatic, twentyeight (46%) had moderate improvement, and four (6%) were mildly improved by a telephone interview (81%) at 22.8 ± 10.7 months postoperatively.ConclusionCatheter-directed thrombolysis with conventional aspiration thrombectomy is an effective treatment for lower extremity deep vein thrombosis and produces satisfactory clinical results.

Preoperative Thrombolysis and Venoplasty Affords no Benefit in Patency Following First Rib Resection and Scalenectomy for Subclavian Vein Thrombosis

Background: Subclavian vein thrombosis is a rare presentation of thoracic outlet syndrome (TOS). Typical treatment patterns consist of preoperative anticoagulation, followed by operative decompression by first rib resection and scalenectomy (FRRS). Recently, thrombolytic therapy has been used as the initial treatment with anticoagulation and FRRS. This study reviewed our extensive experience and compared the effectiveness of preoperative thrombolysis and venoplasty with anticoagulation alone in those undergoing FRRS to preserve subclavian vein patency. Methods: A retrospective review was conducted for all venous TOS patients from July 2003 to May 2009 from a prospectively maintained database. Patient demographics and use of preoperative anticoagulation, thrombolysis, and percutaneous venoplasty were recorded. Reports of follow-up venograms after FRRS were analyzed with regard to axillosubclavian vein patency, percutaneous venoplasty, results of intervention, and presence of occlusions. Postoperative clinic evaluations and duplex imaging reports were reviewed for presence of symptoms, recanalization, chronic nonocclusive thrombus, or continued complete occlusion. Results: A total of 103 patients (53 men, 50 women) had 110 FRRSs for subclavian vein thrombosis, seven of which had contralateral FRRS for thrombosis. The average age was 31 years (range, 16-54 years), with a mean follow-up of 13 months (range, 1-52 months). Overall before FRRS, 65 patients (59%) were managed with anticoagulation alone and 45 (41%) had preoperative endovascular interventions. Of these 45 patients, 22 (49%) underwent thrombolysis alone and 23 (51%) underwent thrombolysis and axillosubclavian balloon venoplasty. After FRRS, 43 patients (96%) had follow-up venograms 2 weeks postoperatively revealing patent subclavian veins in 15 patients, stenosis requiring balloon dilatation in 21, and occlusions in seven (16%). The overall initial patency rate in this group was 84%. In follow-up, recanalization was documented in five of the seven occlusions, with restoration of the patency of the subclavian vein at a mean of 2.8 months postoperatively (range, 1-6 months). In the 65 patients managed with anticoagulation alone before FRRS, 61 (94%) underwent follow-up venograms. The venograms revealed patent subclavian veins in 15 patients, stenosis requiring balloon dilatation in 36, and 10 occlusions (16%). Eight of 10 occlusions were recanalized at an average of 4.3 months (range, 1-11 months) after FRRS. Conclusions: Although initial treatment strategies for subclavian vein thrombosis may differ, a combination of anticoagulation, thrombolysis, operative decompression with FRRS, and postoperative endovascular interventions can yield excellent outcomes. A large proportion of patients in this series (41%) underwent thrombolysis before operative decompression with FRRS but showed no improvement in outcome as determined by vein patency on postoperative venography and duplex imaging during follow-up. Our large series suggests preoperative treatment with anticoagulation alone has vein patency rates similar to patients undergoing thrombolytic therapy. This treatment paradigm also has tremendous cost containment potential given the use of outpatient anticoagulation at the initial presentation has an obvious lower cost than an inpatient endovascular intervention. Overall, 106 of 110 of our patients (96%) had patent subclavian veins during our follow-up interval, were asymptomatic, and back to their previous active lifestyle.

Vena caval thromboses

Background Patients with vena caval (VC) thrombosis have been reported with a variety of clinical presentations, which may create a diagnostic challenge for physicians. Objective The objective of the study was to evaluate the clinical characteristics of patients with VC thrombosis. Patients and Methods Files and all imaging methods of consecutive patients with superior or inferior VC thrombosis with or without pulmonary embolism (PE) between January 26, 2001, and May 12, 2006, were retrospectively studied in detail. Results In our series, VC thromboses within the inferior and superior VC were detected in 28 patients, mostly by combined computed tomographic venography and spiral computed tomographic pulmonary angiography. Nine of these 28 patients (32.1%) had VC thromboses without PE (7 patients with isolated and 2 patients with nonisolated VC thrombosis). Key symptoms and findings in the 9 patients without PE were unexplained dyspnea and tachypnea, respectively. Conclusions Many patients with VC thrombosis do not have peripheral vein thrombosis. Moreover, nearly one third of patients with VC thrombosis have negative pulmonary angiograms but do have dyspnea and tachypnea.

Pulmonary Embolism and Deep Venous Thrombosis in Trauma

Pulmonary embolism (PE) and deep venous thrombosis (DVT) in trauma are related. Retrospective review of medical records. Academic level I trauma center. Trauma patients who underwent computed tomographic pulmonary angiography (CTPA) with computed tomographic venography (CTV) of the pelvic and proximal lower extremity veins over a 3-year period (January 1, 2004, to December 31, 2006) were reviewed. Data on demographics, injury type and severity, imaging findings, hospital length of stay, and mortality were collected. Pulmonary embolism and DVT. Among 247 trauma patients undergoing CTPA/CTV, PE was diagnosed in 46 (19%) and DVT in 18 (7%). Eighteen PEs were central (main or lobar pulmonary arteries), and 28 PEs were peripheral (segmental or subsegmental branches). Pulmonary embolism occurred within the first week of injury in two-thirds of patients. Seven patients with PE (4 femoral, 2 popliteal, and 1 iliac) had DVT. Pulmonary embolism was central in 5 patients and peripheral in 2 patients. No significant differences were noted in any of the examined variables between patients with PE having DVT and those not having DVT. Few patients with PE have DVT of the pelvic or proximal lower extremity veins. Pulmonary embolism may not originate from these veins, as commonly believed, but instead may occur de novo in the lungs. These findings have implications for thromboprophylaxis and, particularly, the value of vena cava filters.

Cerebral Vein and Dural Venous Sinus Thrombosis: Risk Factors, Prognosis and Treatment—a Modern Approach

ABSTRACTCerebral vein and dural venous sinus thrombosis is a rare cause of stroke. It affects between three and four patients per million adults; although the incidence is higher in children and young women. Our understanding of this disease has evolved over the last two decades. Thrombophilia, particularly factor V Leiden and prothrombin gene mutations, as well as oral contraceptive use have been identified as predominant risk factors in contemporary studies compared to infection and puerperium in earlier series. Women of childbearing age account for 75% of cases. Compared to mortality rates in the past, which were as high as 50%, the outcome has improved considerably in recent years—likely due to better management and improved diagnostic capabilities. Approximately 80% of patients will have a meaningful recovery, and in patients receiving anticoagulation the risk of recurrence is about 2%. Magnetic resonance imaging, magnetic resonance venography and computerized tomographic venography have become the methods of choice for diagnosing cerebral vein and dural sinus thrombosis. Anticoagulation with unfractionated heparin and low molecular weight heparin is a well-accepted standard of care even in the presence of concurrent intracranial haemorrhage, while thrombolysis has been used only in selected cases and remains investigational. This review will focus on the presentation and natural history of cerebral vein and sinus thrombosis, risk factors and recommendations for treatment.

Venous Reflux From the Pelvis and Vulvoperineal Region as a Possible Cause of Lower Extremity Varicose Veins

The aim of this study was to demonstrate with the use of computed tomography and ultrasonography that isolated venous reflux from the pelvis and vulvoperineal region is a possible cause of lower extremity varicose veins. From a consecutive series of patients who were referred to the vascular imaging laboratory, we retrospectively selected patients who had unusual lower extremity varicose veins that arose from the pelvis and vulvoperineal region. Computed tomographic venography and ultrasonograhy were used to exclude other causes of varicose veins. We reviewed medical records to evaluate the presence of pelvic congestion syndrome. Computed tomographic findings were reviewed to locate ovarian vein dilatation. Twenty limbs of 15 female patients (age range, 33-72 years; mean age, 53.2 years) were diagnosed with varicose veins that arose from the pelvis and vulvoperineal region without any saphenofemoral insufficiency. Eleven patients (73.3%) had no history of chronic pelvic pain. Four patients (26.7%) presented with chronic pelvic pain without any other evident gynecological etiology. Dilatation of the left ovarian vein was seen in 10 patients (67%; mean dilatation, 8.6 mm; range, 7.5-9.6 mm). Five patients (33%; mean dilatation, 4.9 mm; range, 3.8-6.6 mm) showed no ovarian vein dilatation. The combined use of computed tomographic venography and ultrasonography may be a possible noninvasive method for the diagnosis of unusual lower extremity varicose veins. Venous reflux from the pelvis and vulvoperineal region as a cause of lower extremity varicose veins can manifest without evidence of pelvic congestion syndrome or ovarian vein dilatation.

Volume associated dynamic geometry and spatial orientation of the inferior vena cava

The geometry and dynamics of the vena cava are poorly understood and current knowledge is largely based on qualitative data. The purpose of this study is to quantitate the dimensional changes that occur in the infrarenal inferior vena cava (IVC), in response to changes in intravascular volume. IVC dimensions were measured at 1 cm and 5 cm below the renal veins, on serial contrasted computed tomographic (CT) scans, in 30 severely injured trauma patients during hypovolemic (admission) and fluid resuscitated (follow-up) states. Changes in volume of the infrarenal segment were calculated and correlated with changes in IVC diameter and orientation. The orientation of the infrarenal caval segment was quantified as the angulation of the major axis from the horizontal. A representation of the IVC diameter, as would be seen on standard anterior-posterior venographic imaging, was determined by projecting the CT image of the major axis onto a coronal plane. CT representations of venographic diameters were compared with measurements of the true major axis to assess accuracy of venograms for caval sizing and filter selection. All patients had evidence of a collapsed IVC (<15 mm minor axis dimension) on admission. Mean time between admission and follow-up CT was 49.5 (range: 1-202) days. The volume of the infrarenal segment increased more than twofold with resuscitation, increasing from 6.9 +/- 2.2 (range: 3.1-12.4) mL on admission, to 15.7 +/- 5.0 (range: 9.2-28.5) mL on follow-up (P < .01). At both 1 and 5 cm below the renal veins, the IVC expanded anisotropically such that the minor axis expanded up to five times its initial size accommodating 84% of the increased volume of the segment, while only small diameter changes were observed in the major axis accounting for less than 5% of the volume increase (P < .001). Further, the IVC was left-anterior-oblique in all patients, with the major axis 26 degrees off the horizontal on average. This orientation did not change significantly with volume resuscitation (P > 0.5). The obliquity of the IVC resulted in significant underestimation of caval size of up to 6.8 mm, when using the venographic representation for sizing instead of the true major axis (P < 0.001). In response to changes in intravascular volume, the IVC undergoes profound anisotropic dimensional changes, with greater displacement seen in the minor axis. In addition, the IVC is oriented left-anterior oblique and caval orientation is not altered by changes in volume status. IVC obliquity may result in underestimation of caval size by anterior-posterior venogram.

CT Venous Phase Venography With 64-Detector CT Angiography in the Diagnosis of Acute Pulmonary Embolism

The value of computed tomographic (CT) venography in combination with CT pulmonary angiography has been questioned because of the potential dangers of radiation. Accordingly, we retrospectively evaluated the diagnostic yield of 64-detector CT angiography with CT venography. Among patients who routinely underwent CT venography with CT angiography, the CT angiogram showed acute pulmonary embolism (PE) in 206 of 1903 patients (10.8%). A positive CT venogram in a patient with a negative CT angiogram was shown in 25 of 1903 patients (1.3%). Either the CT angiogram or the CT venogram showed venous thromboembolism in 231 of 1903 patients (12.1%). The proportion of patients with venous thromboembolism diagnosed only by a CT venogram was 25 of 231 (10.8%). In conclusion, the proportion of patients with venous thromboembolism diagnosed only by a CT venogram is sufficiently high to merit consideration of its use especially in those at high risk for DVT.

CT Venography

To demonstrate the use of computed tomographic (CT) venography in selecting a surgical approach for cholesterol granulomas. Retrospective case review. Tertiary referral center. Three patients presented with symptomatic petrous apex cholesterol granulomas with extensive bone erosion involving the jugular fossa. Computed tomographic venography was performed on each patient before selecting a surgical approach for drainage. Localization of the jugular bulb in relation to the petrous carotid artery and basal turn of the cochlea was ascertained in each subject. Three patients with large symptomatic cholesterol granulomas were identified. Conventional CT demonstrated extensive bone erosion involving the jugular fossa in each patient. The location of the jugular bulb and its proximity to the petrous carotid artery and basal turn of the cochlea could not be determined with conventional temporal bone CT and magnetic resonance imaging. Computed tomographic venography provided the exact location of the jugular bulb in all 3 patients. The favorable position of the jugular bulb in all 3 cases permitted drainage of these lesions using an infracochlear approach. Computed tomographic venography provided invaluable information in 3 patients with large symptomatic cholesterol granulomas. All 3 patients were previously thought to be unsuitable candidates for an infracochlear or infralabyrinthine approach because of the unknown location of the jugular bulb.

Evaluation of Posttraumatic Venous Sinus Occlusion With CT Venography

Although cerebral venous sinus occlusion (CVSO) is reported to be associated with intracranial hypertension, its incidence or significance in head trauma is not clear. This study investigated with CT venography the incidence of posttraumatic CVSO, its clinical course, and relation to intracranial hypertension. This study comprised 97 consecutive patients admitted to our Trauma Center from 2002 through 2008 with skull fracture of the petrous portion of the temporal bone or that crossed the dural sinus. Patients with CVSO were examined with CT venography and followed up with CT venography or magnetic resonance imaging. The relation of CVSO to patient outcome and incidence of "talk and deteriorate" was also investigated. CVSO was observed in 22 of 97 patients (22.4%). Mortality was significantly higher in the CVSO group versus no-CVSO group (50.0% vs. 9.3%, p < 0.001). Incidence of lethal intracranial hypertension was higher in the CVSO versus no-CVSO group (40.9% vs. 5.3%, p < 0.001), although there was no difference in Glasgow Coma Scale score at admission between the two groups (CVSO group, 8 +/- 5 vs. no-CVSO group, 10 +/- 4). Recanalization without treatment for CVSO occurred by 6 months in 9 of the 11 survivors (81.8%) who could be followed up. CVSO incidence after head injury was much higher than ever thought. It was associated with mortality and lethal intracranial hypertension, indicating that CVSO may induce acute increase in intracranial pressure in some cases. Early recognition of CVSO may be important to predict deterioration after admission and for starting immediate treatment.

Unusual Causes of Varicose Veins in the Lower Extremities: CT Venographic and Doppler US Findings

There are various causes of varicose veins in the lower extremities. Among the causes are venous insufficiency of the saphenofemoral junction, saphenopopliteal junction, or usual perforating veins. Traditionally, Doppler ultrasonography (US) has been used for evaluation of varicose veins. Sometimes, varicose veins arise from an unexpected anatomic source; in these cases, computed tomographic (CT) venography can provide an overview of the varicose veins. Doppler US with complementary CT venography is useful for determining the precise cause of varicose veins. Between November 2003 and March 2008, the authors evaluated 1350 cases of varicose veins in the lower extremities with both CT venography and Doppler US. The varicose veins were classified according to their causes; unusual causes were studied and included vulvoperineal varicosity, intraosseous perforating vein incompetence, round ligament varicosity, persistent sciatic vein incompetence, Klippel-Trenaunay syndrome, and portosystemic collateral pathways. Radiologists should be familiar with the complete range of primary causes of varicose veins in the lower extremities and with their radiologic manifestations and should recognize the complementary role of CT venography in their evaluation.

Endovascular Management of Deep venous Thrombosis of Lower Extremity in Patients with Malignant Disease

Purpose: To evaluate the efficacy of endovascular management of lower extremity deep vein thrombosis (DVT) in patients with malignant disease. Materials and Methods: Between January 2002 and January 2008, six consecutive patients (5 male and 1 female, mean age-65 years) with lower extremity DVT and malignant disease underwent endovascular management. The duration of symptoms lasted 4-120 days (mean-31 days; 20 days or less in four patients and more than 20 days in two). A catheter-directed thrombolysis was performed via the ipsilateral popliteal vein or common femoral vein, used alone or combined with a percutaneous mechanical thrombectomy. Angioplasty or stent placement was performed in residual stenosis or occlusion of the vein. The follow-up period lasted 1-14 months (mean 7.6 months) and was performed via a color Doppler ultrasonography or computed tomographic venography. Results: Technical success and relief from symptoms was achieved within two days was achieved in five patients. Minor hemorrhagic complications occurred in two cases: hematuria and a hematoma at the puncture site. Upon follow-up, a recurrent DVT occurred in three patients as well as a patent venous flow in two. One patient died within 1 month due to a metastatic mediastinal lymphadenopathy. Conclusion: Endovascular management of the lower extremity DVT is effective for quickly eliminating a thrombus, relieving symptoms, and decreasing hemorrhagic complications in patients with malignant disease.

MDCT venography in the evaluation of inferior vena cava in Budd-Chiari syndrome

To assess the role of multidetector computed tomography (MDCT) venography in the evaluation of the inferior vena cava (IVC) in Budd-Chiari syndrome (BCS), its accuracy as compared to digital subtraction venography (DSV) and the potential of this technique to replace venography for the definitive diagnosis of BCS. Twenty-five suspected cases of BCS were prospectively enrolled in this study and underwent both MDCT venography and DSV. Two observers independently evaluated and graded both the axial and reformatted MDCT images for the presence, site, degree and length of IVC narrowing. The collateral pathways and the hepatic veins were also assessed in all cases. The degree of correlation between MDCT venography and DSV was expressed using Spearman's rank correlation coefficient (Rs). There was excellent correlation between MDCT venography and DSV in predicting the presence of stenosis and in grading the degree and length of IVC stenosis (Rs=0.58, p<0.05). Four patients had presence of a web within the IVC and the reconstructed MDCT venography images detected the flap of the membrane in all of them. In three cases of complete obstruction the cranial extent of the obstruction could be determined on the reconstructed MDCT venography images, while double catheter access through the femoral and jugular routes was needed to determine the same on DSV. MDCT venography was significantly more informative in depicting the presence and site of both intrahepatic and extrahepatic collaterals as compared to DSV. MDCT venography, in the present study, accurately provided information of both conventional CT and IVCgraphy, in the evaluation of the IVC in a non-invasive way. It helped overcome the shortcomings of CT in the evaluation of IVC and was better than DSV for the evaluation of collaterals, calcification and complete IVC obstruction. We suggest that CT venography can be used as a frontline investigation for the diagnosis of IVC obstruction and for planning surgery or percutaneous endovascular intervention.

Endovenous stent-assisted coil embolization for a symptomatic femoral vein aneurysm

An 83-year old man presented with recurrent pulmonary embolism originating from a distal left superficial femoral vein aneurysm despite therapeutic anticoagulation. We treated the patient transluminally using the technique of stent-assisted coil embolization via percutaneous transpopliteal venous access. Follow-up by serial duplex ultrasonography and computer tomographic venography (CTV) demonstrated resolution of the aneurysm. Our case demonstrates that stent-assisted coil embolization may effectively exclude a saccular venous aneurysm and prevent recurrent pulmonary embolization.

Formation of downhill esophageal varices as a rare but serious complication of hemodialysis access: a case report and comprehensive literature review

Proximal or "downhill" esophageal varices are a rare complication of superior vena caval (SVC) obstruction. Few reports describe downhill varices in dialysis patients with catheter-related SVC occlusion. We studied a case of downhill esophageal varices in a dialysis patient from our center and reviewed the published literature on presentation, evaluation and treatment in other dialysis patients (MEDLINE database search). Including our current case, we identified eight reports of dialysis patients with downhill varices. All cases were recognized after presentation with gastrointestinal bleeding, in contrast to low reported bleeding rates of downhill varices in non-dialysis patients. Localized edema and superficial venous engorgement (signs of SVC occlusion) were each observed in four of eight patients. The duration of hemodialysis dependence ranged from 2.5 to 23 years, and dialysis access history included multiple central venous catheters when described (seven cases). Central venous imaging by direct, magnetic resonance or computerized tomographic venography documented SVC stenosis in all cases. Management included percutaneous transluminal angioplasty of the SVC with or without stenting in five of eight patients, three of whom developed restenosis during observation. Successful surgical venous bypass was performed in one patient after failed percutaneous venoplasty. Varices were treated with band ligation in four of eight cases without reported complications. Although rare, downhill esophageal varices should be considered in the differential diagnosis of upper gastrointestinal hemorrhage in dialysis patients exposed to central venous catheters. Diagnosis should prompt radiographic evaluation of SVC patency. Treatment requires timely and coordinated care by specialists in endovascular interventions and gastrointestinal endoscopy.