Journal of Vascular and Interventional Radiology

Global Statement Defining Interventional Radiology

2010-08-01

A consensus statement developed by the Society of Interventional Radiology (SIR, USA), Cardiovascular and Interventional Radiological Society of Europe (CIRSE, Europe), Austrian Society of Interventional Radiology (ÖGIR, Austria), Brazilian Society of Interventional Radiology and Endovascular Surgery (SoBRICE, Brazil), British Society of Interventional Radiology (BSIR, United Kingdom), Bulgarian Society of Interventional Radiology (Bulgaria), Canadian Interventional Radiology Association (CIRA, Canada), CardioVascular and Interventional Radiology Section within the Singapore Radiological Society (CVIR section of the SRS, Singapore), Cardiovascular and Interventional Society of Turkey (TGRD, Turkey), Chinese Society of Interventional Radiology (CSIR, China), Croatian Society of Radiology (CSR, Croatia), Czech Society of Interventional Radiology (CSIR, Czech Republic), Danish Society of Interventional Radiology (DFIR, Denmark), Dutch Society of Interventional Radiology (NGIR, Netherlands), Egyptian Society of Interventional Radiology (ESIR, Egypt), Finnish Society of Interventional Radiology (FSIR, Finland), Georgian Association of Cardiovascular and Interventional Radiology (GACIR, Georgia), German Society of Interventional Radiology and Minimally Invasive Therapy (DeGIR, Germany), Hellenic Society of Interventional Radiology (GSIR, Greece), Hong Kong Society of Interventional Radiology (HKSIR, China), Hungarian Society of Cardiovascular and Interventional Radiology (HSIR, Hungary), IberoAmerican Society of Interventionism (SIDI, Latin America), Indian Society of Vascular and Interventional Radiology (ISVIR, India), Interventional Radiology Section, Polish Medical Society of Radiology (PLTR, Poland), Interventional Radiology Society of Australasia (IRSA, Australia and New Zealand), Irish Society of Interventional Radiology (ISIR, Ireland), Israeli Society of Interventional Radiology (ILSIR, Israel), Japanese Society of Interventional Radiology (JSIR, Japan), Korean Society of Interventional Radiology (KSIR, Korea), Pan Arab Interventional Radiology Society (PAIRS, Lebanon), Philippine Society of Vascular and Interventional Radiology (PSVIR, Philippines), Portuguese Section of Interventional Radiology (NURIP) of the Portuguese Society of Radiology and Nuclear Medicine (SPRMN, Portugal), Section of Cardiovascular and Interventional Radiology of the Royal Belgian Radiological Society (RBRS, Belgium), Seldinger Society of Vascular and Interventional Radiology (SSVIR, Sweden), Sezione di Studio della SIRM di Radiologia Vascolare ed Interventistica (SIRM, Italy), Sociedad Argentina de Radiologia (SAR, Argentina), Society of Interventional Onco-Radiology (RSIOR, Russia), Spanish Society of Vascular and Interventional Radiology (SERVEI, Spain), Swiss Society of Cardiovascular and Interventional Radiology (SSCVIR, Switzerland), Taiwanese Radiological Society (Taiwan), Thai Society of Vascular and Interventional Radiology (TSVIR, Thailand), and the Working Group of Cardiovascular and Interventional Radiology of the Slovak Radiological Society (PSKVIR, Slovak Republic).

We Are IR

John A. Kaufman, Jim A. Reekers — 2010-08-01

THE publication of the Global Statement Defining Interventional Radiology (IR) in this issue comes at a time of critical growth and immense challenges for our specialty (). Image-guided interventions are now as integral to health care as diagnostic imaging. As we see it, there are two potential futures for IR, and both include wide access to image-guided interventional techniques by appropriately trained physicians. However, in one of these futures, IR is also recognized as a unique body of knowledge and practice with a core group of dedicated, organized specialists at its center.

Quality Improvement Guidelines for Uterine Artery Embolization for Symptomatic Leiomyomas

2010-06-16

THE membership of the Society of Interventional Radiology (SIR) Standards of Practice Committee represents experts in a broad spectrum of interventional procedures from both the private and academic sectors of medicine. Generally Standards of Practice Committee members dedicate the vast majority of their professional time to performing interventional procedures; as such, they represent a valid broad expert constituency of the subject matter under consideration for standards production.

Ultrasound-accelerated Thrombolysis in Arterial and Venous Peripheral Occlusions: Fibrinogen Level Effects

Rodney D. Raabe — 2010-08-01

Purpose: This study retrospectively assesses whether significantly accelerating thrombolysis with ultrasound affects fibrinogen levels in the treatment of peripheral arterial occlusions.Materials and Methods: Between December 2005 and August 2007, 38 limbs in 38 patients (17 women; mean age, 60.5 ± 19.7 years; age range, 17–94 years) were treated with ultrasound-accelerated thrombolysis for peripheral arterial occlusion (PAO) and deep vein thrombosis (DVT), with serum fibrinogen levels measured at baseline and every 24 hours. All occlusions were treated with alteplase (0.5–1.0 mg/h).Results: Complete or partial lysis was achieved in 92.1% of patients. All patients received thrombolytic therapy with mean infusion time of 42.3 hours (range, 20–96 hours). As part of standard clinical practice, patients were not assessed angiographically overnight. Mean total alteplase dose was 40.6 mg (range, 18–96 mg). Across all patients, the fibrinogen level at the end of infusion decreased by an average of 18.5% from baseline, and no patient exhibited a fibrinogen level < 100 mg/dL during treatment. Fibrinogen depletion was more pronounced among patients with venous occlusions (26.4% from baseline) than those with arterial occlusions (15.8% from baseline). No major hemorrhagic complications occurred. One patient (2.6%) experienced a minor bleeding event at the access site, and use of thrombolytics was discontinued; and one patient with a chronic arterial occlusion and underlying coronary disease who did not respond to thrombolytic therapy, experienced an acute myocardial infarction. Of documented 30-day clinical outcomes in 20 patients, 80.0% remained patent at 30 days.Conclusions: Ultrasound-accelerated thrombolysis for the treatment of PAO and DVT is associated with a very low complication rate and nominal fibrinogen depletion.

The Safety and Effectiveness of the Retrievable Option Inferior Vena Cava Filter: A United States Prospective Multicenter Clinical Study

2010-07-02

Purpose: To evaluate the safety and effectiveness of the retrievable Option inferior vena cava (IVC) filter in patients at risk for pulmonary embolism (PE).Materials and Methods: This was a prospective, multicenter, single-arm clinical trial. Subjects (N = 100) underwent implantation of the IVC filter and were followed for 180 days; subjects whose filters were later removed were followed for 30 days thereafter. The primary objective was to determine whether the one-sided lower limit of the 95% CI for the observed clinical success rate was at least 80%. Clinical success was defined as technical success (deployment of the filter such that it was judged suitable for mechanical protection from PE) without subsequent PE, significant filter migration or embolization, symptomatic caval thrombosis, or other complications.Results: Technical success was achieved in 100% of subjects. There were eight cases of recurrent PE, two cases of filter migration (23 mm), and three cases of symptomatic caval occlusion/thrombosis (one in a subject who also experienced filter migration). No filter embolization or fracture occurred. Clinical success was achieved in 88% of subjects; the one-sided lower limit of the 95% CI was 81%. Retrieval was successful at a mean of 67.1 days after implantation (range, 1–175 d) for 36 of 39 subjects (92.3%). All deaths (n = 17) and deep vein thromboses (n = 18) were judged to have resulted from preexisting or intercurrent illnesses or interventions and unrelated to the filter device; all deaths were judged to be unrelated to PE.Conclusions: Placement and retrieval of the Option IVC filter were performed safely and with high rates of clinical success.

Use of a Latest-generation Vascular Plug for Peripheral Vascular Embolization with Use of a Diagnostic Catheter: Preliminary Clinical Experience

2010-06-03

Purpose: The latest-generation Amplatzer vascular plug (AVP), the AVP 4, is designed for embolization of smaller vessels without a sheath or guiding catheter. This study evaluated the AVP 4 in peripheral vascular embolization.Materials and Methods: Embolization with the AVP 4 was attempted in 13 patients (11 men) for trauma (n = 7) and other indications (n = 6). Technical success rate, vascular bed, size of catheter, and number and size of AVP 4 devices were recorded.Results: Embolization with the AVP 4 was successful in 10 of 13 patients (77%). In trauma patients (n = 7), embolization of the splenic artery (n = 4), lumbar artery (n = 2), and superior gluteal artery (n = 1) was performed. In other patients, preoperative embolization of the right portal vein (n = 1), a gastric varix after transjugular intrahepatic portosystemic shunt creation (n = 1), an aneurysm of the internal iliac artery (n = 1), and inferior mesenteric artery (IMA) embolization before aneurysm repair (n = 2) was performed. Sizes of the AVP 4 were 4 mm (n = 6), 6 mm (n = 5), and 8 mm (n = 1). In all patients, 4- and 5-F catheters with a 0.038-inch minimum inner lumen were used. In one patient, IMA embolization was attempted via a femoral approach but was unsuccessful as a result of repeated catheter tip dislocation because of acute angle; coils were used instead.Conclusions: Peripheral embolization with the AVP 4 was successful in the majority of patients. Future comparative study is necessary to evaluate this device's benefits over other embolization materials such as earlier-generation AVPs or microcoils.

Prospective Randomized Comparative Evaluation of Proximal Valve Polyurethane and Distal Valve Silicone Peripherally Inserted Central Catheters

Cheng K. Ong, Sudhakar K. Venkatesh, Gabriel B. Lau, Shih C. Wang — 2010-07-02

Purpose: The objective of this study was to evaluate and compare the relative durability and complications between the proximal valve polyurethane and distal valve silicone peripherally inserted central catheters (PICCs).Methods: Institutional review board approval was obtained. A total of 326 patients (mean age, 50.4 years) was assigned randomly to receive either a proximal valve polyurethane PICC (n = 198) or a distal valve silicone Groshong PICC (n = 194). All PICCs were inserted under radiologic guidance by interventional radiologists. Follow-up data were collected until catheter removal because of complications or treatment completion.Results: The mean catheter dwell time was 25.6 days (range, 1–245 days). Complications were encountered in 26.8% and 47.9% of the proximal valve polyurethane PICCs and distal valve silicone PICCs, respectively (P < .001). Significantly higher incidences of phlebitis (23.2% versus 11.6%, P = .003) and catheter-related infection (6.2% versus 2%, P = 0.043) were noted in the distal valve silicone PICCs. No significant differences in the incidence of catheter occlusion, fracture, or dislodgement were found. Multivariate logistic regression analysis showed a higher complication rate in the distal valve silicone PICCs corrected for patients' age, sex, underlying morbidity, indication, peripheral vein accessed, arm used, catheter tip placement, and the number of venepunctures attempted.Conclusions: Proximal valve polyurethane PICCs were more durable than distal valve silicone PICCs, which were associated with a higher incidence of phlebitis and infection, probably related to the materials of the catheters and the designs and placements of the catheter valves.

The Effectiveness of Locoregional Therapies versus Supportive Care in Maintaining Survival within the Milan Criteria in Patients with Hepatocellular Carcinoma

2010-08-01

Purpose: To compare survival after treatment with either locoregional therapy (LRT) or supportive care in patients with hepatocellular carcinoma (HCC) within the Milan criteria.Materials and Methods: Patients with HCC who were classified within the Milan criteria (solitary HCC ≤ 5 cm or ≤ 3 tumors with none greater than 3 cm in largest diameter, and no macrovascular invasion) and underwent transcatheter therapy or radiofrequency ablation (RF ablation) between 1998 and 2008 were retrospectively studied. Patients with tumor burden within the Milan criteria who received the best supportive care only were used as the control group. Survival within the Milan criteria was compared between those who underwent LRT and patients who underwent supportive care.Results: Of 162 patients studied, 110 patients (67.9%) underwent LRT, and 52 patients (32.1%) received supportive care alone. Median survival within the Milan criteria for patients who did and did not receive LRT were 644 days (95% confidence interval [CI], 193–1094) and 162 days (95% CI, 73–250) respectively (P < .001). In patients who received LRT, Child Pugh class was prognostic for survival within the Milan criteria on multivariate analysis (P = .002, hazard ratio 5.16 [2.69–9.89]). The long-term survival for patients who did not undergo transplant was 502 days (95% CI, 91–912) in patients who received LRT and 151 days (95% CI, 59–242) in patients who were treated with supportive care (P < .001).Conclusions: LRT is more effective than supportive care in prolonging survival within the Milan criteria in patients with HCC. The long-term survival in patients not undergoing transplant was significantly longer for patients who received LRT than for patients who were treated with supportive care.

CME Test Questions

2010-08-01

Radioembolization with Use of Yttrium-90 Resin Microspheres in Patients with Hepatocellular Carcinoma and Portal Vein Thrombosis

2010-07-02

Purpose: Intraarterial delivery of yttrium-90 (90Y)–bound microspheres (ie, radioembolization) is a promising treatment for hepatocellular carcinoma (HCC). An early concern was the “embolic” nature of the microspheres, and their potential to reduce hepatic arterial blood flow in patients with compromised portal blood flow secondary to portal vein thrombosis/occlusion (PVT). In this situation, the risk of liver failure could be enhanced, particularly in patients with cirrhosis who have increased hepatic arterial blood flow. This retrospective analysis was undertaken to assess the safety and clinical benefits of radioembolization with 90Y resin microspheres in HCC with branch or main PVT.Materials and Methods: A total of 25 patients presenting with unresectable HCC and compromised portal flow received segmental, lobar, or whole-liver infusion of 90Y resin microspheres. For the analysis of tumor response, changes in target lesions, appearance of new lesions, and changes in portal vein thrombus were studied. Controlled disease was defined by absence of progression in all these components.Results: Globally, controlled disease was achieved in 66.7% of patients at 2 months and 50% of patients at 6 months. No significant changes were observed in liver-related toxicities according to Common Toxicity Criteria (version 3.0) at 1 and 2 months after treatment. Median survival time was 10 months (95% CI, 6.6–13.3 months).Conclusions: Radioembolization of unresectable HCC and branch or main PVT with 90Y resin microspheres was associated with minimal toxicity and a favorable median survival time. Further prospective studies are warranted to validate the findings in this clinically challenging patient population.

Safety of Yttrium-90 Microsphere Radioembolization in Patients with Biliary Obstruction

2010-07-02

Purpose: There are few data on radioembolization in the setting of biliary obstruction. The present study was performed to assess the safety of yttrium-90 (90Y) radioembolization in the setting of tumor-related biliary obstruction and total bilirubin levels of 2 mg/dL or lower.Materials and Methods: Twelve patients with liver tumors underwent 19 treatment sessions with 90Y to the obstructed liver lobe or segment. Initial bilirubin level was 2 mg/dL or lower in all cases. Measured outcomes included pre- and posttreatment white blood cell (WBC) count, total bilirubin level, and alkaline phosphatase (ALP) level. Bilirubin toxicities and biliary complications were assessed according to Common Toxicity Criteria, version 3.0.Results: Lobar or segmental 90Y was successful in all cases. Pre- and posttreatment median WBC counts (5.3 vs 5.3; P = .490), bilirubin levels (1.0 vs 1.1; P = .460), and ALP levels (195 vs 146; P = .712) showed no differences. One case of grade 3 bilirubin toxicity was noted in a patient with liver hilar nodal progression and subsequent biliary obstruction requiring external drainage. Complete resolution of biliary obstruction was seen after 90Y treatment in one case of metastatic colorectal carcinoma at 1 month follow-up. No biliary complications (infection, sepsis, biliary necrosis, biloma formation, abscess development, or biliary stricture) were encountered in this cohort during an overall median follow-up time of 22.9 months.Conclusions: The use of 90Y glass microspheres demonstrated a good safety profile in the setting of tumor-related biliary obstruction in patients with normal or near-normal bilirubin levels in this series, without evidence of therapy-related progressive leukocytosis, bilirubin increase, or infectious or biliary complications after treatment.

Hypersensitivity Reactions to Transcatheter Chemoembolization with Cisplatin and Lipiodol Suspension for Unresectable Hepatocellular Carcinoma

2010-07-09

Purpose: To assess the predictors of hypersensitivity reaction to chemoembolization procedures with cisplatin and Lipiodol suspension for the treatment of hepatocellular carcinoma (HCC).Materials and Methods: Between February 2005 and December 2008, 434 patients with HCC were treated with chemoembolization with a cisplatin and Lipiodol suspension. This retrospective cohort study analyzed the incidence of hypersensitivity reactions as an adverse effect and their predictors by multivariate logistic regression analyses.Results: In total, 847 chemoembolization procedures were carried out in 434 patients. The median number of procedures per patient was 2 (range, 1–12). Mean dose of cisplatin per chemoembolization session was 27 mg (range, 15.0–80.0 mg), and the median total dose of cisplatin per patient was 55 mg (range, 5.0–560.0 mg). Hypersensitivity reactions occurred in 14 patients (1.7%). The median number of chemoembolization procedures in these patients was 7 (range, 3–10). Mean dose of cisplatin per session was 22 mg (range, 9.2–35.7 mg), and the median total dose of cisplatin was 134 mg (range, 37–286 mg). On multivariate analysis, the only parameter that showed an independent association with hypersensitivity reactions was the performance of 3 or more than three chemoembolization procedures.Conclusions: Performance of more than three chemoembolization procedures with a cisplatin and Lipiodol suspension was found to be independently associated with hypersensitivity reactions. Patients undergoing repeated chemoembolization procedures with cisplatin and Lipiodol suspension may experience hypersensitivity reactions as an adverse effect.

Chemoembolization for the Treatment of Large Hepatocellular Carcinoma

2010-07-02

Purpose: To retrospectively evaluate the efficacy of chemoembolization for inoperable hepatocellular carcinoma (HCC) tumors larger than 5 cm in diameter.Materials and Methods: Chemoembolization was performed in 30 patients with HCCs with a largest diameter of more than 5 cm with three or fewer lesions and no portal vein tumor thrombus. The mean maximum tumor diameter was 7.7 cm ± 2.4. When the tumor was extremely large and had multiple feeding arteries, stepwise chemoembolization sessions at intervals of 3–10 weeks were performed. In addition, extrahepatic collateral supply was identified and embolized. Local therapeutic effects, survival rates, and complications were analyzed.Results: The mean follow-up period was 33.8 months ± 24.1. One to 13 chemoembolization sessions (mean, 4.0 sessions ± 3.0) were performed in each patient. Additionally, 62 collateral vessels were embolized in 21 patients, including 22 vessels in 14 patients at the initial procedure. Early tumor response rate 2–3 months after treatment was 43.3% by Response Evaluation Criteria In Solid Tumors. Complete radiologic response was achieved in 19 patients. Eleven patients died between 4 and 61 months after treatment (mean, 27.2 months ± 21.8), including four deaths unrelated to hepatic causes. Nineteen patients have survived for 6–103 months (mean, 37.5 months ± 25.2). Overall and progression free-survival rates at 1, 3, and 6 years were 82.3% and 66.0%, 73.9% and 57.6%, and 32.9% and 34.2%, respectively. Three infectious complications developed and were managed by interventions.Conclusions: Chemoembolization was effective for large HCCs, although there is a risk of infectious complications after the procedure.

A Lung Biopsy Tract Plug for Reduction of Postbiopsy Pneumothorax and Other Complications: Results of a Prospective, Multicenter, Randomized, Controlled Clinical Study

2010-08-01

Purpose: To evaluate the ability of an expanding hydrogel lung biopsy tract plug (“plug”) to reduce rates of pneumothoraces and other complications associated with computed tomography (CT)-guided lung biopsy.Materials and Methods: A total of 339 subjects (mean age, 67 years) who underwent lung biopsy of indeterminate masses, without immediate postsample CT evidence of a pneumothorax, were randomized at 15 U.S. centers. Treatment subjects (n = 170) received a plug deployed through the coaxial needle just before the needle was removed. Control subjects (n = 169) did not receive a plug. The primary end point was defined as the absence of pneumothorax on chest radiographs at all three required postprocedure assessments (30- to 60-minute, 24-hour, 30-day); analysis was stratified by any smoking history and study site. A central laboratory performed blinded independent interpretation of the radiographs.Results: Among the 287 subjects who completed all postprocedure assessments, significantly more treatment subjects than control subjects achieved the primary end point (127 of 150, 85% vs 95 of 137, 69%; P = .002). Among all 339 randomized subjects, the odds of achieving the primary end point were 4.4 times greater for nonsmokers than they were for smokers (95% confidence interval, 1.7, 11.0; P = 0.002); study site had no statistically significant effect. Compared with control subjects, treatment subjects had fewer pneumothoraces (30 of 170, 18% vs 53 of 169, 31%), fewer chest tubes placed (6 of 170, 4% vs 18 of 169, 11%), and fewer postbiopsy hospital admissions (16 of 170, 9% vs 23 of 169, 14%).Conclusions: The lung biopsy tract plug significantly reduced rates of pneumothorax in patients undergoing CT-guided lung biopsy. Rates of chest tube placement and postprocedure hospital admission were also reduced.

Radiologic Placement of Uncovered Stents for the Treatment of Malignant Colorectal Obstruction

Sue Yon Kim, Se Hwan Kwon, Joo Hyeong Oh — 2010-07-02

Purpose: To evaluate the effectiveness of radiologic placement of uncovered stents for the treatment of malignant colorectal obstruction.Materials and Methods: From May 2003 to January 2008, 116 radiologic placements of uncovered stents were attempted in 99 patients (M:F, 59:40; mean age, 65 years) with malignant colorectal obstructions. The location of stent insertion, technical and clinical success, complication rates, and patency rates of the stents in a palliative group were also evaluated. In the palliative group, the follow-up period was 2–455 days (mean, 100 ± 129 days).Results: Radiologic stent placement was technically successful in 110 of 116 cases (94.8%). Fifty cases of stent placement were preoperative (45.5%, 50 of 110) and 60 (54.5%, 60 of 110) were performed with palliative intents. In five of six failed cases, the replacement of the stent was later performed with the assistance of colonoscopy. One patient underwent an emergency operation. In 98 of 110 cases, the symptoms of obstruction were relieved, for a clinical success rate of 89.1%. Of the 50 stents that were placed successfully with preoperative intent, 44 patients underwent surgery within a mean of 10.3 days. In the palliative group, the patency rates were 89.7% at 1 month, 85.6% at 3 months, 80.8% at 6 months, and 72.7% at 12 months.Conclusions: The radiologic placement of uncovered stents for the treatment of malignant colorectal obstruction is feasible and safe and provides acceptable clinical results not only for preoperative decompression but also for palliative cases, especially in left-sided colonic obstructions.

What do Family Physicians Know about Interventional Radiology? A Survey of Family Physicians at a Large Canadian Annual Scientific Assembly

Philip S. Mok, Eva Y. Tan, Mark O. Baerlocher, Sriharsha Athreya — 2010-04-22

Purpose: To quantify the level of background knowledge among family physicians with regard to interventional radiology (IR) procedures, duties, and clinical responsibilities and to develop recommendations on how to further educate family physicians in IR.Materials and Methods: Paper surveys were administered to family physicians who attended the Ontario College of Family Physicians' Annual Scientific Assembly. Each survey consisted of 14 questions pertaining to IR procedures, clinical duties, collaboration, and education.Results: A total of 213 of 229 (93%) attempted paper surveys were completed. Family physicians rated their knowledge of IR as poor (31%), adequate (53%), good (14%), or excellent (2%). A total of 98%, 71%, 47%, and 38% correctly identified that interventional radiologists performed image-guided biopsies, uterine artery embolization, radiofrequency ablation of tumors, and vascular angioplasties, respectively. Only 7% correctly identified that interventional radiologists are currently not recognized as distinct subspecialists by the Royal College of Physicians and Surgeons of Canada. Approximately 71% would refer patients directly to an interventional radiologist. A total of 96% believed that future education about IR would be “very” or “somewhat” helpful. Approximately 43% selected presentations given by interventional radiologists at family medicine conferences as their preferred method of future education.Conclusions: The data quantify and demonstrate the knowledge gap that exists among family physicians in Canada regarding IR procedures, duties, and responsibilities. Family physicians strongly support future education and collaboration with interventional radiologists. Eight results-based recommendations are made to further educate family physicians about IR and promote increased collaboration.

Increased Expression of HIF-1α, VEGF-A and Its Receptors, MMP-2, TIMP-1, and ADAMTS-1 at the Venous Stenosis of Arteriovenous Fistula in a Mouse Model with Renal Insufficiency

Sanjay Misra, Uday Shergill, Binxia Yang, Rajiv Janardhanan, Khamal D. Misra — 2010-07-02

Purpose: A mouse model of renal insufficiency with arteriovenous fistula (AVF) and venous stenosis was created. The authors tested the hypothesis that there is increased gene expression of hypoxia-inducible factor-1 alpha (HIF-1α); vascular endothelial growth factor-A (VEGF-A) and its receptors (VEGFR-1, -2); matrix metalloproteinase-2 (MMP-2), -9 (MMP-9); tissue inhibitor of metalloproteinase-1, -2 (TIMP-1, -2); and a disintegrin and metalloproteinase thrombospondin-1 (ADAMTS-1) at the venous stenosis.Materials and Methods: Nineteen male C57BL/6 mice underwent a left nephrectomy and a surgical occlusion of the right upper pole to induce renal function characterized in eight animals. Twenty eight days later, an AVF (n = 11) was created from the right carotid artery to ipsilateral jugular vein, and the mice were killed at day 7 (n = 4) and day 14 (n = 4). The outflow and control veins were removed for gene expression. Three mice were killed at day 28 for histologic analysis.Results: The mean serum blood urea nitrogen level remained significantly elevated for 8 weeks when compared with baseline (P < .05). By day seven, there was a significant increase in the expression of HIF-1α, VEGF-A, VEGFR-1, VEGFR-2, MMP-2, TIMP-1, and ADAMTS-1 at the outflow vein, with HIF-1α and TIMP-1 levels significantly elevated at day 14 (P < .05). By day 28, the venous stenosis was characterized by a thickened vein wall and neointima.Conclusions: A mouse model of renal insufficiency with AVF was developed that had increased expression of HIF-1α, VEGF-A, VEGFR-1, VEGFR-2, MMP-2, TIMP-1, and ADAMTS-1 at the outflow vein with venous stenosis by day 28.

Paclitaxel-induced Arterial Wall Toxicity and Inflammation: Tissue Uptake in Various Dose Densities in a Minipig Model

2010-08-01

Purpose: Paclitaxel is an antiproliferative agent in drug-eluting stents with largely unknown tissue interaction. Toxicity might result from overdosage and/or accumulation. Part 1 of this two-step study investigated how paclitaxel uptake depends on dose density, coronary drug transfer kinetics, and elution efficacy.Materials and Methods: With cobalt chromium stents and Polyzene-F nanoscale coating, low, intermediate, and high paclitaxel dose densities (25 μg, 50 μg, and 150 μg per stent) were investigated in porcine right coronary arteries (RCAs). Coronary and myocardial tissue concentration measurements and determination of on-stent paclitaxel and plasma concentrations were performed at 2, 8, 24, and 72 hours.Results: For all stents, uptake was similar at all time intervals (paclitaxel RCA concentration range, 1,610–33,300 ng). Low- and intermediate-dose stents showed similar RCA concentrations, but those for high-dose stents were three times greater. Residual on-stent paclitaxel concentration was not time-dependent, at 33.3% on low-, 30.6% on intermediate-, and 17.4% on high-dose stents. Paclitaxel was measurable in only the plasma immediately after stent placement, with a linear dose relationship and a timely regression: measurements in high-dose stents were 0.0454–0.656 ng/mL at 1 minute and 0.0329–0.0879 ng/mL at 5 minutes. Untreated control samples of the left coronary artery showed a linear dose-dependent concentration (12.6 ng/g, 21.2 ng/g, and 85.2 ng/g).Conclusions: Overall coronary paclitaxel uptake is fairly independent from the baseline overall dose density and, hence, depends on immediate binding mechanisms of the arterial wall. This is supported by the fact that, regardless of the applied dose density, the kinetics of paclitaxel uptake did not follow an exposure time pattern.

Interventional Therapy of Head and Neck Cancer with Lipid Nanoparticle–carried Rhenium 186 Radionuclide

2010-05-17

Purpose: Minimally invasive interventional cancer therapy with drug-carrying lipid nanoparticles (ie, liposomes) via convection-enhanced delivery by an infusion pump can increase intratumoral drug concentration and retention while facilitating broad distribution throughout solid tumors. The authors investigated the utility of liposome-carrying β-emitting radionuclides to treat head and neck cancer by direct intratumoral infusion in nude rats.Materials and Methods: Four groups of nude rats were subcutaneously inoculated with human tongue cancer cells. After tumors reached an average size of 1.6 cm3, the treatment group received an intratumoral infusion of liposomal rhenium-186 (186Re) (185 MBq [5 mCi]/cm3 tumor). Three control groups were intratumorally infused with unlabeled liposomes, unencapsulated 186Re-perrhenate, or unencapsulated intermediate 186Re compound (186Re-N,N-bis[2-mercaptoethyl]-N′,N′-diethyl-ethylenediamine [BMEDA]). In vivo distribution of 186Re activity was measured by planar γ-camera imaging. Tumor therapy and toxicity were assessed by tumor size, body weight, and hematology.Results: Average tumor volume in the 186Re-liposome group on posttreatment day 14 decreased to 87.7% ± 20.1%, whereas tumor volumes increased to 395.0%–514.4% on average in the other three groups (P< .001 vs 186Re-liposome). The 186Re-liposomes provided much higher intratumoral retention of 186Re activity, resulting in an average tumor radiation absorbed dose of 526.3 Gy ± 93.3, whereas 186Re-perrhenate and 186Re-BMEDA groups had only 3.3 Gy ± 1.2 and 13.4 Gy ± 9.2 tumor doses, respectively. No systemic toxicity was observed.Conclusions: Liposomal 186Re effectively treated head and neck cancer with minimal side effects after convection-enhanced interventional delivery. These results suggest the potential of liposomal 186Re for clinical application in interventional therapy of cancer.

Tissue Contraction Caused by Radiofrequency and Microwave Ablation: A Laboratory Study in Liver and Lung

Christopher L. Brace, Teresa A. Diaz, J. Louis Hinshaw, Fred T. Lee — 2010-05-31

Purpose: To determine the amount of tissue contraction during radiofrequency (RF) and microwave ablation.Materials and Methods: Markers were inserted into explanted bovine liver and lung 10 mm (inner), 20 mm (middle; not used in lung), and 30 mm (peripheral) diametrically around an ablation applicator. Aside from unablated controls, RF and microwave ablations 25–30 mm in diameter were then created and sectioned to measure the distance between markers (n = 12, liver RF; n = 8, other). Total contraction was calculated by subtracting postablation measurements from controls at each position. Relative contraction was calculated by subtracting the nearest more central measurement. Sample water content was measured to determine the relationship between dehydration and relative contraction. A mixed-effects model tested for differences in diameters, total and relative contraction, and water content with energy, tissue, and marker position as independent variables.Results: Total contractions at the inner, middle, and peripheral positions in liver were 2.9 mm (31%), 4.8 mm (24%), and 4.5 mm (15%) for RF and 3.6 mm (38%), 6.6 mm (33%), and 9.0 mm (30%) for microwave, respectively. Significantly more contraction was noted in lung (P < .001): 5.1 mm (55%) and 14.2 mm (49%) for RF and 4.8 mm (52%) and 13.7 mm (47%) for microwave at the inner and peripheral positions, respectively. Microwaves produced more contraction than RF in liver (P < .05) but not in lung. A positive correlation between dehydration and relative contraction was observed in all cases.Conclusions: Ablation-induced tissue contraction is substantial and influenced by dehydration. Contraction should be considered when testing devices and computer models or comparing pre- and postablation images.

A Rat Esophageal Model to Investigate Stent-induced Tissue Hyperplasia

Eun-Young Kim, Ji Hoon Shin, Yoon Young Jung, Dong-Ho Shin, Ho-Young Song — 2010-08-01

Purpose: To evaluate the feasibility of stent placement and the formation of tissue hyperplasia caused by stent placement in a rat esophageal model.Materials and Methods: Twenty Sprague-Dawley rats were divided into four groups to assess differing stent diameters and design (group I, 4 mm diameter and a large mesh gap; group II, 5 mm diameter and a large mesh gap; group III, 5 mm diameter and a small mesh gap; and group IV, barbs added to the group III stents). Follow-up, 1-week, and 3-week esophagograms were obtained. Rats were euthanized 3 weeks after stent placement. Microscopic findings were evaluated in groups with an incidence of less than 50% stent migration.Results: Stent placement was technically successful in all rats, and there were no procedure-related complications. No esophageal perforation occurred during follow-up. The incidence of stent migration was 100%, 60%, 40%, and 0% in groups I through IV, respectively. The esophagi with stent migration showed only a small amount of tissue hyperplasia; however, esophagi without stent migration showed gross tissue hyperplasia through the mesh. The microscopic findings were evaluated in groups III and IV. The degree of inflammatory cell infiltration, papillary projection thickness, granulation tissue area, and percentage of the granulation tissue area were higher in group IV than in group III; however, there was no statistical significance.Conclusions: Esophageal stent placement was feasible in a rat model, and formation of tissue hyperplasia was evident in rats without stent migration. With barbed stents, there was the least incidence of stent migration without esophageal perforation.

Fragmentation, Embolization, and Left Ventricular Perforation of a Recovery Filter

Benoit Desjardins, Sadashiv H. Kamath, David Williams — 2010-07-02

The Recovery retrievable inferior vena cava filter (C. R. Bard, Tempe, Arizona) was approved in the United States for temporary and permanent prophylaxis against pulmonary embolism. A few reports in the literature document fracture and migration of the Recovery filter or filter fragments into the heart. The authors report a case of delayed intracardiac migration of a fractured wire from this filter and describe the clinical course of a patient in whom this complication was managed.

Hepatic Artery Infusion Catheter Implantation without Embolization of the Gastroduodenal Artery in Cases of Retrograde Blood Flow

2010-07-02

Between January 2007 and January 2008, a port/catheter system for hepatic arterial infusion chemotherapy was implanted in seven patients with retrograde blood flow in the gastroduodenal artery (GDA). The GDA was not coil-embolized when the catheter tip was positioned in the right gastroepiploic artery. In all cases, implantation of the port/catheter system was successful, and there were no complications. Interventionalists can economize on expensive microcoils by using this simple and time-saving method.

Massive Hepatic Necrosis with Gastric, Splenic, and Pancreatic Infarctions after Ethanol Ablation for Hepatocellular Carcinoma

2010-07-02

Hepatic necrosis after ethanol ablation for hepatocellular carcinoma (HCC), although rare, is well known and described, particularly in patients with chronic liver disease. The present report describes a rare case of massive hepatic necrosis with partial gastric, splenic, and pancreatic infarctions after local treatment of liver HCC with ethanol ablation and discusses the reasons for this complication. With the increasing use of percutaneous techniques to treat liver tumors, it is imperative for the interventional radiologist to be aware of the potential vascular complications of these techniques. An appreciation of vascular anatomy via multidetector computed tomography (CT) and/or magnetic resonance (MR) angiography is important when planning image-guided interventions.

Subclavian Venous Aneurysm: Endovascular Treatment

Enrique M. San Norberto, Vicente M. Gutiérrez, Álvaro Revilla, Carlos Vaquero — 2010-05-31

Few cases of venous aneurysm involving the subclavian vein have been reported in the literature to date, and all were treated conservatively or with surgical excision. The present report describes a 73-year-old woman with a pulmonary thromboembolism that likely originated from a large right subclavian vein aneurysm that was treated by percutaneous endovascular means. The technique involved placement of a self-expanding stent in the parent vein across the aneurysm, followed by filling of the lumen of the aneurysm with coils through a microcatheter. The patient has remained symptom-free at 18-month follow-up.

Ice Ball Fractures during Percutaneous Renal Cryoablation: Risk Factors and Potential Implications

2010-07-09

The authors present two cases of ice ball fractures with associated hemorrhage during percutaneous renal cryoablation procedures. Although this is a rare occurrence, it is important to be able to identify ice ball fractures on monitoring noncontrast computed tomography (CT) scans during cryoablation, because they can result in significant bleeding, and recognition allows prompt intervention. Risk factors for ice ball fractures and potential implications are discussed.

Percutaneous Repair of a Nonunion Pubic Ramus Fracture Using a Metallic Stent Scaffold and Cement Osteoplasty

John W. Kamysz — 2010-07-02

This report describes a case of repair of a nonunion pubic ramus fracture with intramedullary placement of a self-expanding nitinol stent across a fracture gap to provide a permeable scaffold for polymethylmethacrylate (PMMA) cement to track across the fracture gap and to restrict leakage into surrounding soft tissues. The patient presented with an 8-month history of pelvic pain and debility. His pain remains resolved after 14 months. Percutaneous repair of nonunion pubic rami fractures using a bridging metallic stent in combination with PMMA bone cement may be an effective treatment for these fractures.

Direct Percutaneous Embolization of a Renal Pseudoaneurysm with Use of N-Butyl Cyanoacrylate

Cori E. Caughlin, Martin E. Simons, Michael A. Robinette — 2010-07-02

A 27-year-old woman with tuberous sclerosis presented with gross hematuria, syncope, and a decrrease in hemoglobin to 69 g/L (normal range, 120–160 g/L). Computed tomographic (CT) angiography revealed diffusely enlarged kidneys characterized by multiple bilateral vascular fat-containing masses consistent with angiomyolipomas. A 2.5-cm pseudoaneurysm with surrounding thrombus was noted, within one of the angiomyolipomas at the upper pole of the left kidney. The pseudoaneurysm was confirmed angiographically (, a). Endovascular treatment was attempted, but ultimately proved unsuccessful. Although multiple renal artery branches were subselected with a microcatheter, the arterial branch supplying the pseudoaneurysm could not be selectively catheterized for safe embolization.

Abstracts of Current Literature

2010-08-01

Randon C, Jacobs B, De Ryck F, et al. Angioplasty or primary stenting for infrapopliteal lesions: results of a prospective randomized trial. Cardiovasc Intervent Radiol 2010; 33:260–269.

Editorial Board

2010-08-01

Advertisers' Index

2010-08-01

Business Information

2010-08-01

Forthcoming Articles: September 2010

2010-08-01

Spinal Cord Protection with Cerebrospinal Fluid Drains in a Patient Undergoing Thoracic Endovascular Aortic Repair Cuong H. Lam and Geogy Vatakencherry

Journal of Vascular and Interventional Radiology

Global Statement Defining Interventional Radiology

We Are IR

Quality Improvement Guidelines for Uterine Artery Embolization for Symptomatic Leiomyomas

Ultrasound-accelerated Thrombolysis in Arterial and Venous Peripheral Occlusions: Fibrinogen Level Effects

The Safety and Effectiveness of the Retrievable Option Inferior Vena Cava Filter: A United States Prospective Multicenter Clinical Study

Use of a Latest-generation Vascular Plug for Peripheral Vascular Embolization with Use of a Diagnostic Catheter: Preliminary Clinical Experience

Prospective Randomized Comparative Evaluation of Proximal Valve Polyurethane and Distal Valve Silicone Peripherally Inserted Central Catheters

The Effectiveness of Locoregional Therapies versus Supportive Care in Maintaining Survival within the Milan Criteria in Patients with Hepatocellular Carcinoma

CME Test Questions

Radioembolization with Use of Yttrium-90 Resin Microspheres in Patients with Hepatocellular Carcinoma and Portal Vein Thrombosis

Safety of Yttrium-90 Microsphere Radioembolization in Patients with Biliary Obstruction

Hypersensitivity Reactions to Transcatheter Chemoembolization with Cisplatin and Lipiodol Suspension for Unresectable Hepatocellular Carcinoma

Chemoembolization for the Treatment of Large Hepatocellular Carcinoma

A Lung Biopsy Tract Plug for Reduction of Postbiopsy Pneumothorax and Other Complications: Results of a Prospective, Multicenter, Randomized, Controlled Clinical Study

Radiologic Placement of Uncovered Stents for the Treatment of Malignant Colorectal Obstruction

What do Family Physicians Know about Interventional Radiology? A Survey of Family Physicians at a Large Canadian Annual Scientific Assembly

Increased Expression of HIF-1α, VEGF-A and Its Receptors, MMP-2, TIMP-1, and ADAMTS-1 at the Venous Stenosis of Arteriovenous Fistula in a Mouse Model with Renal Insufficiency

Paclitaxel-induced Arterial Wall Toxicity and Inflammation: Tissue Uptake in Various Dose Densities in a Minipig Model

Interventional Therapy of Head and Neck Cancer with Lipid Nanoparticle–carried Rhenium 186 Radionuclide

Tissue Contraction Caused by Radiofrequency and Microwave Ablation: A Laboratory Study in Liver and Lung

A Rat Esophageal Model to Investigate Stent-induced Tissue Hyperplasia

Fragmentation, Embolization, and Left Ventricular Perforation of a Recovery Filter

Hepatic Artery Infusion Catheter Implantation without Embolization of the Gastroduodenal Artery in Cases of Retrograde Blood Flow

Massive Hepatic Necrosis with Gastric, Splenic, and Pancreatic Infarctions after Ethanol Ablation for Hepatocellular Carcinoma

Subclavian Venous Aneurysm: Endovascular Treatment

Ice Ball Fractures during Percutaneous Renal Cryoablation: Risk Factors and Potential Implications

Percutaneous Repair of a Nonunion Pubic Ramus Fracture Using a Metallic Stent Scaffold and Cement Osteoplasty

Direct Percutaneous Embolization of a Renal Pseudoaneurysm with Use of N-Butyl Cyanoacrylate

Abstracts of Current Literature

Editorial Board

Advertisers' Index

Table of Contents

Business Information

Forthcoming Articles: September 2010