Update on Preoperative Embolization of Bone Metastases.

Management of patients with bone metastasis is complex and should include different specialties. Goals of therapy should be identified for each individual patient prior to the start of treatment. Preoperative embolization has generally been considered a safe and effective means of reducing intraoperative blood loss with recent studies and advances in technique reported. Update on indications, contraindications, technique, and efficacy, as well as prognostic factors and complications of preoperative embolization of bone metastases will be reviewed. New trends such as transradial arterial access and usage of liquid embolic agents will be discussed. Large tumor size, increased preprocedural tumor vascularity, longer embolization-to-surgery interval, and radical surgical procedures are associated with greater intraoperative blood loss and prolonged operative time. An accurate, noninvasive method to evaluate tumor vascularity prior to angiography is needed to identify patients who are most likely to benefit from preoperative embolization. Particular attention will be paid to skeletal metastases and spinal metastases as each has its own set of complexity.

Percutaneous treatment of IVC obstruction due to post-resection hepatic torsion associated with IVC thrombosis.

BACKGROUND: Migration of the left hepatic lobe into the potential space following right lobe resection can result in torsion and hepatic venous outflow obstruction with compromised venous return from the IVC. If untreated, significant morbidity and mortality can develop. CASE PRESENTATION: We report a case of a 29-year-old female with Lynch syndrome who underwent right lobe resection for a metastatic hepatic tumor. There was subsequent migration of the liver remnant, torsion of the IVC, and impaired hepatic outflow, successfully treated with thrombectomy and stenting. CONCLUSION: Following right hepatectomy, hepatic venous outflow obstruction should be consdered in the setting of hepatorenal failure and hemodynamic instability. Endovascular stenting is a viable treatment option.

Complications and Retrieval Data of Vena Cava Filters Based on Specific Infrarenal Location.

PURPOSE: Although recommended placement of IVC filters is with their tips positioned at the level of the renal vein inflow, in practice, adherence is limited due to clinical situation or IVC anatomy. We seek to evaluate the indwelling and retrieval complications of IVC filters based on their specific position within the infrarenal IVC. MATERIALS AND METHODS: Retrospective, single institution study of 333 consecutive infrarenal vena cava filters placed by interventional radiologists in patients with an average age of 62.2 ± 15.7 years was performed between 2013 and 2015. Primary indication was venous thromboembolic disease (n = 320, 96.1%). Filters were classified based on location of the apex below the lowest renal vein inflow on the procedural venogram: less than 1 cm (n = 180, 54.1%), 1-2 cm (n = 96, 28.8%), and greater than 2 cm (n = 57, 17.1%). Denali (n = 171, 51.4%) and Celect (n = 162, 48.6%) filters were evaluated. CT follow-up, indwelling complications, and retrieval data were obtained. RESULTS: Follow-up CT imaging performed for symptomatic indications occurred for 38.3% of filters placed < 1 cm below the lowest renal vein, 27.1% of filters placed 1-2 cm, and 36.8% placed > 2 cm (p = .16). There was no difference in caval strut penetration, penetration of adjacent viscera, time to penetration, filter migration, or tilt (p = .15, .27, .41, .57, .93). No filter fractures occurred. There was no difference in the incidence of breakthrough PE or complex filter retrieval (p = .83, .59). Only one retrieval failure occurred. CONCLUSIONS: This study suggests filter apex location within the infrarenal IVC, including placement > 2 cm below the level of the renal vein inflow, is not associated with differences in indwelling or retrieval complications. LEVEL OF EVIDENCE: Level 3 non-randomized controlled follow-up study.

Indwelling and Retrieval Complications of Denali and Celect Infrarenal Vena Cava Filters.

PURPOSE: To compare indwelling and retrieval complications of Denali and Celect filters placed in the infrarenal inferior vena cava (IVC). MATERIALS AND METHODS: A retrospective study was conducted over 2 years at a single institution in which 171 Denali and 162 Celect filters were placed in 333 patients with a mean age of 62.3 years ± 15.7 (161 men; 48.3%). Filter indications included venous thromboembolic disease (n = 320; 96.1%) and surgical prophylaxis (n = 13; 3.9%). A jugular approach was used to place 303 filters (91.0%). Computed tomography (CT) follow-up, complications, and retrieval data were obtained. RESULTS: Follow-up CT imaging was performed on 58 filters from each group with lower incidences of caval strut penetration (one vs 12) and filter tilt (one vs 15) in the Denali filter group (P = .002 and P < .001, respectively). There was no difference in incidences of breakthrough pulmonary embolism (P = .68). Retrieval attempts were performed on 43 Denali and 53 Celect filters with mean indwelling times at retrieval of 128.2 and 144.1 days, respectively (P = .40). Mean fluoroscopy time at retrieval was lower in the Denali group (3.1 min vs 6.0 min; P = .01). There were fewer cases of complex retrieval in the Denali group (n = 2 vs 10; P = .06). Tilt, fluoroscopy time, and air kerma were associated with complex retrieval (P = .04, P < .001, and P < .001, respectively). There was one Denali filter deployment complication that led to retrieval failure. CONCLUSIONS: This study suggests that Denali filters are associated with lower incidences of strut penetration and filter tilt as well as shorter fluoroscopy time at retrieval compared with Celect filters when placed in the infrarenal IVC.

Comparison of combination therapies in the management of hepatocellular carcinoma: transarterial chemoembolization with radiofrequency ablation versus microwave ablation.

PURPOSE: To compare retrospectively the outcomes and complications of transcatheter arterial chemoembolization with drug-eluting embolic agents combined with radiofrequency (RF) ablation or microwave (MW) ablation in treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From 2003-2011, 89 patients with HCC received a combination therapy-transcatheter arterial chemoembolization plus RF ablation in 38 patients and transcatheter arterial chemoembolization plus MW ablation in 51 patients. Local tumor response, tumor progression-free survival (PFS), overall PFS, overall survival (OS), and complications were compared. Overall PFS and OS were compared between the two treatment groups in multivariate analysis controlling for Child-Pugh class, Barcelona Clinic Liver Classification stage, and index tumor size. RESULTS: Complete local tumor response was achieved in 37 (80.4%) of the tumors treated with transcatheter arterial chemoembolization plus RF ablation and 49 (76.6%) of the tumors treated with transcatheter arterial chemoembolization plus MW ablation (P = .67). The median tumor PFS and overall PFS were 20.8 months and 9.3 months (P = .72) for transarterial chemoembolization plus RF ablation and 21.8 months and 9.2 months for transarterial chemoembolization plus MW ablation (P = .32). The median OS of the transcatheter arterial chemoembolization plus RF ablation group was 23.3 months, and the median OS of the transcatheter arterial chemoembolization plus MW ablation group was 42.6 months, with no significant difference in the survival experience between the two groups (log-rank test, P = .10). In the multivariate analysis, Barcelona Clinic Liver Classification stage was the only factor associated with overall PFS and OS. One patient in the transcatheter arterial chemoembolization plus RF ablation cohort (3%) and two patients in the transcatheter arterial chemoembolization plus MW ablation cohort (4%) required prolonged hospitalization (< 48 h) for pain management after the procedure (P = 1.00). CONCLUSIONS: Based on similar safety and efficacy outcomes, both combination therapies, transcatheter arterial chemoembolization plus RF ablation and transcatheter arterial chemoembolization plus MW ablation, are effective treatments for HCC.

Unintended thermal injuries from radiofrequency ablation: organ protection with an angioplasty balloon catheter in an animal model.

OBJECTIVES: The aim of this study was to investigate a novel approach of using a balloon catheter as a protective device to separate liver from the diaphragm or nearby bowel during radiofrequency ablation (RFA) of hepatic dome tumors in an animal model. MATERIALS AND METHODS: All experimental procedures were approved by animal Institutional Review Board. Using a 3 cm RF needle electrode, 70 hepatic ablation zones were created using ultrasound in 7 pigs. 50 lesions were created using balloon interposition between liver and diaphragm; 20 lesions were created using the balloon device interposed posteriorly between liver and bowel. Additional 21 control lesions were performed. Animals were sacrificed immediately; diaphragm and bowel were then visually inspected and sectioned. Diaphragmatic and bowel injury was then classified according to the depth of thickness. RESULTS: Control lesions caused full thickness injury, either to diaphragm or bowel. During ablation of lesions with balloon interposition, there was significantly less diaphragmatic injury, P < 0.001 and less bowel injury, P < 0.01. CONCLUSION: Using balloon interposition as a protective device has advantages over previous saline infusion or CO2 insufflation, providing a safe way to expand percutaneous RFA of liver tumors located on the undersurface of the diaphragm. In addition, this method may be used in protection of other organs adjacent to areas being ablated.

Combined pharmacomechanical thrombolysis of complete portomesenteric thrombosis in a liver transplant recipient.

Treatment options for portomesenteric venous thrombosis range from anticoagulation to surgery, depending on chronicity, severity of symptoms, extent of thrombosis, and the availability of local expertise. For acute and subacute cases, a variety of endovascular options have been described in limited published series and case reports, including thrombolysis and mechanical thrombectomy. We report what is to our knowledge the first case in which the Trellis pharmacomechanical thrombolysis device was used successfully to treat complete acute thrombosis of the entire superior mesenteric vein and the entire portal vein with extension into all segmental intrahepatic portal branches in a young adult after liver transplantation. This device, coupled with adjunctive techniques using balloon catheters, facilitated complete restoration of flow, resulting in graft salvage and long-term patency.

Long-term outcomes of percutaneous venoplasty and Gianturco stent placement to treat obstruction of the inferior vena cava complicating liver transplantation.

PURPOSE: Evaluation of long-term outcomes of venoplasty and Gianturco stents to treat inferior vena cava (IVC) obstruction after liver transplantation. METHODS: We retrospectively analyzed records from 33 consecutive adult patients referred with the intent to treat suspected IVC obstruction after liver transplantation. Treatment was performed for occlusion or stenosis with a gradient exceeding 3 mmHg. The primary treatment was venoplasty and, if refractory, Gianturco stent placement. Recurrence prompted repeat venoplasty or stent placement. RESULTS: Of the 33 patients, 25 (aged 46.9 ± 12.2 years) required treatment at a mean of 2.3 years (14 days to 20.3 years) after transplantation. For technically successful cases, primary treatment was venoplasty alone (14) or with stent placement (10). Technical success was 96 % (24 of 25) reflecting failure to cross one occlusion. Clinical success was 88 % (22 of 25) reflecting the technical failure and two that died of unrelated complications within 5 weeks. Cumulative primary patencies were 57.1 % at 6 months (n = 21) and 51.4 % at 1 (n = 10), 3 (n = 7), 5 (n = 6), and 7 (n = 5) years. Cumulative primary assisted patency was 95.2 % at 6 months (n = 21) and at 1 (n = 15), 3 (n = 9), 5 (n = 8), and 7 (n = 8) years. The 17 patients stented for refractory (n = 10) or recurrent (n = 7) stenosis had cumulative primary and primary assisted patencies of 86.0 and 100 %, respectively, from 6 months (n = 14) to 7 years (n = 3). No major complications occurred; one fractured stent was observed after 11.6 years. CONCLUSION: For IVC obstruction following liver transplantation, excellent long-term outcomes can be achieved by venoplasty and Gianturco stent placement.

Percutaneous thrombin injection in an infant to treat hepatic artery pseudoaneurysm after failed embolization.

Percutaneous thrombin injection has been described in case reports as an alternative to surgical intervention for the treatment of hepatic artery pseudoaneurysms associated with high-grade liver lacerations in adults. However, there is limited description in the literature of this technique being applied in children, particularly in preadolescents, and no published literature describes its use in infants. The procedure can be performed by pediatric radiologists and pediatric interventional radiologists skilled in ultrasound-guided aspiration techniques. We report successful application of percutaneous thrombin injection in an infant to treat a pseudoaneurysm of a left hepatic arterial branch in an 11-month-old girl with a grade IV liver laceration after superselective transcatheter arterial embolization failed to achieve thrombosis.

The RETRIEVE trial: safety and effectiveness of the retrievable crux vena cava filter.

PURPOSE: To evaluate the safety and effectiveness of the Crux vena cava filter in patients at risk for pulmonary embolism (PE). MATERIALS AND METHODS: The Crux Biomedical Evaluation of the Crux Inferior Vena Cava Filter System trial was an international prospective, multicenter, single-arm clinical trial in 125 patients implanted with the Crux filter between June 2010 and June 2011. Follow-up was 180 days after filter placement and 30 days after filter retrieval. The primary objective was to determine whether the clinical success rate was at least 80%. Clinical success was defined as technical success of deployment and freedom from definite PE, filter migration, and device-related adverse events requiring intervention. RESULTS: The clinical success rate was 96.0% (120 of 125), with a one-sided lower limit of the 95% confidence interval of 91.8%. The rate of technical success was 98.4% (123 of 125). There were three cases of definite PE (2.4%), two cases of deployment failure, and no cases of device migration, embolization, fracture, or tilting. Investigators observed nine cases of thrombus (all nonocclusive) in or near the filter (six during retrieval evaluation vena cavography, two during computed tomography [CT] scans for PE symptoms, and one during CT for cancer management) and 13 cases of deep vein thrombosis. Device retrieval was attempted at a mean of 84.6 days±57.6 (range, 6-190 d) after implantation and was successful for 98.1% of patients (53 of 54). All deaths (n = 14) were determined to be unrelated to the filter or PE. CONCLUSIONS: The Crux vena cava filter performed safely, with high rates of clinical, technical, and retrieval success.

Difficult OptEase filter retrievals after prolonged indwelling times.

PURPOSE: The OptEase vena cave filter (Cordis, Piscataway, NJ) is commercially available as a retrievable or permanent filter with short recommended indwelling time, presumably due to extensive contact of the filter side struts with the inferior vena cava wall and subsequent neointimal hyperplasia leading to incorporation. Our purpose was to evaluate OptEase filter retrievals with a long indwelling time period that required unconventional retrieval techniques. MATERIALS AND METHODS: We retrospectively reviewed patients who underwent OptEase filter retrieval with long undwelling times requiring additional maneuvers for retrieval. Techniques used included rigid endobronchial forceps dissection and wire-through-loop snare. Each patient underwent postretrieval venogram to evaluate for possible complications. In addition, patients had clinical follow-up 2 weeks after the retrieval procedure. RESULTS: There were three patients (2 women, 1 man; average age 64 years) who underwent OptEase filter retrieval. The mean indwelling time was 6.4 months. The indwelling filters were successfully retrieved. There were no complications. Postprocedural follow-up showed no clinical pathology. CONCLUSION: Unconventional techniques aided in the retrieval of OptEase filters with long indwelling times.

Metastatic Insulinoma Following Resection of Nonsecreting Pancreatic Islet Cell Tumor: A Case Report and Review of the Literature.

A 56-year-old woman presented to our clinic for recurrent hypoglycemia after undergoing resection of an incidentally discovered nonfunctional pancreatic endocrine tumor 6 years ago. She underwent a distal pancreatectomy and splenectomy, after which she developed diabetes and was placed on an insulin pump. Pathology showed a pancreatic endocrine neoplasm with negative islet hormone immunostains. Two years later, computed tomography scan of the abdomen showed multiple liver lesions. Biopsy of a liver lesion showed a well-differentiated neuroendocrine neoplasm, consistent with pancreatic origin. Six years later, she presented to clinic with 1.5 years of recurrent hypoglycemia. Laboratory results showed elevated proinsulin, insulin levels, and c-peptide levels during a hypoglycemic episode. Computed tomography scan of the abdomen redemonstrated multiple liver lesions. Repeated transarterial catheter chemoembolization and microwave thermal ablation controlled hypoglycemia. The unusual features of interest of this case include the transformation of nonfunctioning pancreatic endocrine tumor to a metastatic insulinoma and the occurrence of atrial flutter after octreotide for treatment.

Evaluation and treatment of suspected type II endoleaks in patients with enlarging abdominal aortic aneurysms.

PURPOSE: To evaluate angiographic diagnosis and embolotherapy of patients with enlarging abdominal aortic aneurysms and computed tomographic (CT) diagnosis of type II endoleak. MATERIALS AND METHODS: A retrospective review was performed of all patients referred to a single vascular and interventional radiology section from January 1, 2003, to June 1, 2011, with a diagnosis of enlarging aneurysm and type II endoleak. Twenty-five patients underwent 40 procedures between 12 and 82 months after endograft insertion (mean, 48 mo) for diagnosis and/or treatment of endoleaks. RESULTS: Type II endoleaks were treated with cyanoacrylate, coils, and ethylene vinyl alcohol copolymer in 16 patients. Technical success rate was 88% (14 of 16 patients) and clinical success rate was 100% (16 of 16 patients). Aneurysm growth was arrested in all cases over a mean follow-up of 27.5 months (range, 6-88 mo). Endoleaks in nine patients were misclassified on CT; two had type I endoleaks and seven had type III endoleaks. Four of the nine patients (two type I endoleaks and two type III endoleaks) were correctly classified after initial angiography. The other five type III endoleaks were correctly classified on CT after coil embolization of the inferior mesenteric artery. Direct embolization was performed via sac puncture with ethylene vinyl alcohol copolymer in two of the latter five patients and eliminated endoleaks in both. CONCLUSIONS: Aneurysm growth caused by type II endoleaks was arrested by embolization. CT misclassification occurred relatively commonly; type III endoleaks purported to be type II endoleaks were found in 28% of patients (seven of 25).

Use of retrievable filters in alternative common iliac vein location in high-risk surgical patients.

PURPOSE: To evaluate the use of retrievable filters placed in bilateral common iliac veins in high-risk surgical patients. MATERIALS AND METHODS: During the 4-year study period, 10 patients received bilateral common iliac vein placement of retrievable filters for pulmonary embolism (PE) prophylaxis. These patients were at risk for venous thromboembolism (VTE) but had no evidence of VTE at the time of filter placement. In nine patients undergoing bariatric surgery, placement of a filter in the inferior vena cava (IVC) was impossible because of megacava (defined as caval diameter ≥ 3.0 cm). In one patient who had planned dissection of an extensive retroperitoneal tumor, there was concern that IVC location of the filter would be prone to complications secondary to intraoperative manipulation. Filter placement and retrieval were evaluated. All patients were followed clinically until 4-6 weeks after filter retrieval. RESULTS: There were 20 filters placed in 10 attempts, 18 (nine patients) through the right internal jugular vein and 2 (one patient) through bilateral femoral veins. The mean (± standard deviation) dwell time of the filters was 40 days ± 10 (range 30-71 days). All filters were successfully removed. There were no procedural complications. No clinically evident PE was noted. CONCLUSIONS: Use of retrievable filters in the bilateral common iliac veins was found to be feasible and effective in preventing PE in patients with contraindications to filter placement in the IVC.

Iatrogenic portobiliary fistula treated by stent-graft placement.

Stent-graft exclusion of an ischemic, hilar portobiliary fistula after liver transplantation has not been reported. Isolated reports have described peripheral or nonischemic fistulas, and alternative treatment options have ranged from balloon tamponade to surgical repair. We present a unique case of a hilar portobiliary fistula successfully treated to resolution by unilateral placement of a stent-graft.

Techniques used for difficult retrievals of the Günther Tulip inferior vena cava filter: experience in 32 patients.

PURPOSE: To retrospectively review experience with difficult retrievals of Günther Tulip filters (GTFs) in which various techniques were used. MATERIALS AND METHODS: From December 2004 to December 2006, 32 patients were referred to a single radiology department for GTF retrieval (25 women and seven men; mean age, 40 years; range, 21-60 y). All patients were evaluated, and 22 of these patients had undergone unsuccessful filter retrieval attempts elsewhere. In the remaining patients, significant tilt of the filter (n = 8) or difficult internal jugular vein access (n = 2) discouraged retrieval attempts. There were a total of 38 filters. Twenty-five patients had a filter in the infrarenal inferior vena cava (IVC). Among the remaining seven patients, six had bilateral iliac filters and one had a left iliac filter. Retrievals were performed via conventional technique-ie, by snaring the hook of the filter without additional maneuvers-or other techniques. RESULTS: Thirty-seven of 38 filters were successfully removed, for a success rate of 97%. Successful retrievals were performed with conventional (n = 4), catheter twist (n = 3), modified snare (n = 15), loop snare (n = 14), and balloon dilation (n = 1) techniques. The average dwell time for filters successfully removed was 58 days (range, 22-258 d). One failure occurred in a patient who had undergone unsuccessful retrieval previously. The hook of the filter and a displaced secondary strut, which had migrated superiorly, were incorporated into the IVC wall in this case. CONCLUSIONS: Additional maneuvers were useful in these difficult retrievals of GTFs that might not otherwise be retrievable with the conventional method.