Presence Of Collateral Veins Research Articles

Multimodality imaging evaluation of arteriovenous fistulas and grafts: a clinical practice review.

Arteriovenous fistulas (AVFs) and grafts (AVGs) are the preferred forms of vascular access for hemodialysis in patients with severe renal dysfunction. Multimodality imaging plays an important role in the pre-procedural evaluation of these patients. Ultrasound is often used for pre-procedural vascular mapping in preparation for the creation of an AVF or AVG. Pre-procedural mapping includes a comprehensive evaluation of the arterial and venous vasculature including evaluation of vessel diameter, stenosis, course, presence of collateral veins, wall thickness and wall abnormalities. Computed tomography (CT), magnetic resonance imaging (MRI) or catheter angiography are used when sonography is not available or when further characterization of sonographic abnormalities is required. Following the procedure, routine surveillance imaging is not recommended. If there are any clinical concerns or if physical examination is inconclusive, further evaluation with ultrasound is warranted. Ultrasound allows for assessment of vascular access site maturation by evaluating the time-averaged blood flow and helping characterize the outflow vein in the case of an AVF. CT and MRI can play a complementary role to ultrasound. Vascular access site complications include non-maturation, aneurysm, pseudoaneurysm, thrombosis, stenosis, steal phenomena or occlusion typically of the outflow vein, infection, bleeding and rarely angiosarcoma. In this article, we review the role of multimodality imaging in the pre- and post-procedural evaluation of patients with AVF and AVG. Additionally, novel technologies of vascular access site creation using endovascular techniques and upcoming non-invasive imaging techniques for evaluation of AVFs and AVGs are discussed.

Diagnostic accuracy of the jetting sign and a dilatation ratio of left renal vein in CT urography for detecting anterior nutcracker syndrome

To investigate the diagnostic value of computed tomography (CT) urography findings of anterior nutcracker syndrome (NCS). The study included patients with left renal vein (LRV) compression at the aortomesenteric portion at CT urography who underwent renal venography or cystoscopy. Patients with a renocaval pressure gradient of ≥3 mmHg on renal venography or bloody urine jetting from the left ureteral orifice on cystoscopy were defined as the NCS group; the remaining patients comprised the non-NCS group. CT findings were analysed using the jetting of contrast medium flow from the LRV to the inferior vena cava (jetting sign), aortomesenteric distance, presence of collateral veins, and a dilatation ratio of LRV diameter at the aortomesenteric portion (arterial phase/delayed phases). Clinical findings, including age, gender, and body-mass-index, were also analysed. CT features and clinical findings were compared between the NCS and non-NCS groups. Diagnostic performance of CT parameters was assessed using receiver operating characteristic curve analysis. A total of 70 patients (21 men, mean age 44.4±17.2 years) with NCS (n=13) and non-NCS (n=57) were included. Younger age (<40 years), presence of the jetting sign, and a lower dilatation ratio of LRV diameter between the arterial and delayed phases (<1.7) were found to be significant independent factors for predicting the NCS group (OR 24.5, 18.9, 19.4, respectively, p<0.05 for all). The combination of the presence of the jetting sign and a dilatation ratio of LRV diameter of <1.7 obtained the highest AUC of 0.88. The jetting sign and the dilatation ratio of LRV diameter between the arterial and delayed phases can both be very useful in the diagnosis of anterior nutcracker syndrome during CT urography.

C-arm-based flat-panel detector cone-beam computed tomography venography in the diagnosis of iliac vein compression syndrome.

Background:C-arm-based flat-panel detector cone-beam computed tomography (CBCT) venography has never been used in the management of iliac vein compression syndrome (IVCS). This study aimed to determine the technical feasibility and safety of CBCT venography in the diagnosis of IVCS compared with conventional venography (CV).Methods:Twenty patients with clinical manifestations of lower extremity venous insufficiency were prospectively enrolled between May 2018 and December 2018. Each patient underwent both CV and CBCT venography. The feasibility and safety of CBCT venography were assessed by technical success rate and complication rate. The relationships between the clinical indexes and the results of CBCT venography and CV were analyzed with correlation analysis. The consistency of the diagnosis of IVCS using each modality was analyzed by the kappa test.Results:The technical success rate was 100% for CBCT venography and for CV, without any complications. Compared with CV, CBCT venography was able to show more details of adjacent tissues which might be helpful for making etiological diagnosis. The stenosis rate under CBCT venography had excellent consistency with that under CV (kappa = 0.78, Chi-square test). The stenosis rate under CBCT venography was positively correlated with the presence of collateral veins (odds ratio 1.12, 95% confidence interval: [1.00, 1.26], P = 0.049), while the stenosis rate under CV was not. Unexpectedly, only one patient had a venous pressure gradient of more than 2 mmHg (1 mmHg = 0.133 kPa).Conclusions:For the diagnosis of IVCS, C-arm-based CBCT venography was technically feasible, with good safety. The presence of collateral veins on CBCT was clinically significant. A C-arm fluoroscopy-based technique that combines CV and CBCT might be a promising protocol for the management of IVCS during a single session.

Interrupting Rivaling Access-flow with Nonsurgical Image-guided ligation: the "IRANI" Procedure.

The presence of collateral veins is one of the most common causes of fistula failure to mature. The traditional approach to eliminate collateral vessel flow is coil embolization under fluoroscopy or surgical cut down and branch vessel ligation. However, both approaches are expensive and time consuming. Here, we described an image-guided nonsurgical method to ligate collateral veins. The collateral veins were ligated using Hawkins-Akins needle under ultrasound guidance. The average time for one ligation procedure was 17 minutes. There was a significant increase of blood flow in the venous outflow postligation procedure. Four weeks postprocedure ultrasound demonstrated occlusion of the target vessels. This procedure was well tolerated without major complications. In summary, the novel procedure described here offers an image-guided nonsurgical approach for collateral vein occlusion.

Acute deep vein thrombosis (DVT) of the lower limbs in a 32-year-old man with chronic hypoplasia of the inferior vena cava (HIVC) without risk factors

The anomalies of the inferior vena cava (IVC) have an incidence between 0.2 and 1 % in the general population [1]. The normal average diameter of the IVC is 17.5 mm (up to 25 mm maximum) and the spectrum of anatomical abnormalities of the IVC (e.g., absence or interruption of the vessel or variation in diameter) can be responsible for serious hemodynamic effects to the venous circulation of the lower limbs (i.e., venous stasis), and be a risk factor for the development of deep vein thrombosis (DVT). The association between hypoplasia of the IVC (HIVC) and DVT has been previously reported, even though the association of absence of the IVC and DVT is more frequently recorded [2]. Hypoplasia of the inferior vena cava should be taken into account when an unexplained DVT occurs in young patients, as DVT can occur in up to 5 % of young adults with IVC anomalies [3]. A 32-year-old man was referred to our Unit of Internal Medicine because of acute and intense back pain. History was unrevealing for risk factors related to venous disease, but the man had remained immobilised 3–4 days because of the intense pain. After admission, he underwent full (abdominal and pelvic) ultrasound examination, which revealed bilateral proximal (iliac–femoral veins) DVT (Fig. 1a, b; see Fig. 1c for comparison) and severe dilatation of the superficial venous circle of the lower limbs. Laboratory investigations for thrombophilic defects (including factor V Leiden, prothrombin G20210A, mutations A1298C and C8677T, proteins C and S and antithrombin III) were all negative. A computed tomography (CT scan) study of the superior abdomen showed hypoplasia of inferior vena cava (diameter 11 9 5 mm) along with bilateral thrombosis of the iliac and hypogastric veins; the right iliac vein was dilated and the paralumbar veins were hypertrophic; dilatation of the right hypogastric venous circle was present (Fig. 2a; see Fig. 2b for comparison). Treatment with subcutaneous low molecular weight heparin was initiated, and shortly followed by oral anticoagulant therapy (INR range 3.0) with application of stocking bandage compression to the lower limbs. Currently, the man is still under follow-up at our unit: his general condition is good with no further recorded episodes of thrombosis; he is still taking oral anticoagulant therapy. Anomalies of the IVC are a rare finding in clinical practice, but should be suspected when an unexplained DVT presents in a young adult, particularly in the absence of risk factors such as inherited thrombophilia. The main findings in patients with DVT and HICV are summarised in Table 1. Notably, dilatation of the ascending lumbar veins, paravertebral venous plexus, azygous and hemiazygous veins are typical imaging findings of these patients. The hemodynamic data on venous return from the lower part of the body are crucial for differentiating acute and chronic anomalies of the IVC. Although ultrasonography is useful to demonstrate anomalies of the IVC, by revealing the lack of continuity of the IVC segment and the presence of collateral veins in the abdomen or in the retroperitoneal region, the gold standard of imaging is a CT scan (Fig. 2) or magnetic resonance imaging studies, which are more sensitive and specific in showing the anomalies of the IVC, and to explain the & Salvatore Santo Signorelli ssignore@unict.it

330 PERCUTANEOUS VARICOCELE EMBOLIZATION IN CHILDREN: COMPARISON OF PRIMARY VS. SALVAGE THERAPY

You have accessJournal of UrologyPediatrics: Andrology-Cryptorchidism & Varicoceles1 Apr 2011330 PERCUTANEOUS VARICOCELE EMBOLIZATION IN CHILDREN: COMPARISON OF PRIMARY VS. SALVAGE THERAPY Sylvia Montag, Arvin George, Soroush Rais-Bahrami, Zhamshid Okhunov, Ardeshir Rastinehad, David Siegel, and Lane S. Palmer Sylvia MontagSylvia Montag New Hyde Park, NY More articles by this author , Arvin GeorgeArvin George Mineola, NY More articles by this author , Soroush Rais-BahramiSoroush Rais-Bahrami New Hyde Park, NY More articles by this author , Zhamshid OkhunovZhamshid Okhunov New Hyde Park, NY More articles by this author , Ardeshir RastinehadArdeshir Rastinehad Bethesda, MD More articles by this author , David SiegelDavid Siegel New Hyde Park, NY More articles by this author , and Lane S. PalmerLane S. Palmer New Hyde Park, NY More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.413AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The treatment of varicocele by percutaneous embolization of the internal spermatic vein is a safe and effective technique with the potential of minimizing the morbidity traditionally associated with surgical management. The purpose of this study is to compare procedure characteristics of primary intervention versus salvage therapy for the treatment of clinically significant varicoceles in the pediatric population. METHODS A retrospective chart review of patients under 22 years presenting for percutaneous varicocele embolization was performed. Patient demographic and procedural characteristics were collected including patency of gonadal vein, number of divisions of gonadal vein, presence of retroperitoneal or inguinal collaterals, flouroscopy time, number of coils used, and postoperative complications. Patients were stratified according to primary varicoceles versus those with prior failed surgical varicocelectomy. Data was analyzed using Chi-square analysis and t-test where appropriate. RESULTS A total of 62 patients were underwent treatment with a mean age of 16.3 years (11–21). Mean followup was 8.8 months. There was no significant difference in presence of inguinal or retroperitoneal collaterals, or gonadal vein patency between the groups. Additionally, no difference was seen in flouroscopy time though there a greater number of microembolization coils were used for salvage treatment (9 vs. 13.9, p=0.012). CONCLUSIONS Salvage selective gonadal vein embolization is not associated with the presence of collateral veins. The primary reason for failed surgical varicocelectomy is a patent gonadal vein in the pediatric population. Salvage therapy did not result in increased radiation exposure © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e133-e134 Peer Review Report Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sylvia Montag New Hyde Park, NY More articles by this author Arvin George Mineola, NY More articles by this author Soroush Rais-Bahrami New Hyde Park, NY More articles by this author Zhamshid Okhunov New Hyde Park, NY More articles by this author Ardeshir Rastinehad Bethesda, MD More articles by this author David Siegel New Hyde Park, NY More articles by this author Lane S. Palmer New Hyde Park, NY More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Gonadal vein recruitment in renal cell carcinoma: Incidence, pathogenesis and clinical significance

Objective: Gonadal vein recruitment by collateral veins in patients with renal cell carcinoma is not routinely searched for during abdominal computed tomography. We performed a retrospective view to determine the incidence of gonadal vein recruitment for collateral venous drainage in patients with renal cell carcinoma and we discuss its potential importance. Patients and methods: Abdominal CT examinations were available for 58 of 95 patients with renal cell carcinoma identified during a 3-year-period. The presence of collateral veins and recruitment of the ipsilateral gonadal vein was recorded and correlated with the estimated blood loss at surgery. Results: Eighteen of 58 tumours were small (less than 5 cm). Multiple (greater than three) collateral renal capsular veins were noted in 26 of 58 patients and few (less than three) were noted in 11. Recruitment of the gonadal vein (range 4–18 mm, mean 8 mm) was seen in 18 of 58 patients (31%) who all had multiple collaterals. Gonadal vein recruitment was only seen in patients with tumours greater than 5 cm. Mean estimated blood loss at surgery was significantly different ( P < 0.001) in 18 of 58 patients (mean, 1078 ml) with gonadal vein recruitment compared to 40 of 58 patients (mean 304 ml) without distinct visualization of the gonadal vein and compared to 22 of 40 patients with large tumours (mean 368 ml). Conclusion: Gonadal vein recruitment signifies well-developed arteriovenous shunting and high flow collateral venous drainage pathways and may be used as an index of tumour vascularity. This finding may have clinical potential in triaging patients toward pre-operative renal embolization.

Sonographic diagnosis of subclavian and internal jugular vein thrombosis.

Seven patients with internal jugular and/or subclavian vein thrombosis were studied with real-time sonography and venography. High-resolution real-time sonography was used to tabulate morphologic parameters (venous size, shape, intraluminal echoes, and presence of collateral veins), as well as physiologic parameters (mobile venous valves, distention, compressibility, pulsation). Chronic venous thrombosis was characterized by the presence of collateral veins, spread of the thrombus to other major veins, and loss of normal vascular landmarks with poor visualization of the actual thrombus, the "cut-off sign." Acute catheter-induced thrombosis was confined to one vessel, and the thrombus was seen clearly in all cases. Two new signs of thrombosis, the absence of the beating venous valve and the "cut-off sign," are particularly useful in the sonographic diagnosis of internal jugular vein thrombosis.

Wedged hepatic venography in patients with end-to-side portacaval shunts.

Wedged hepatic venograms in patients with end-to-side portacaval shunts were evaluated with regard to the sinusoidal filling pattern; the presence of portal vein and hepatic vein filling; the direction of washout of contrast medium; and the presence of collateral veins between the hepatic and splanchnic sides of the shunt.