For Hepatocellular Carcinoma Treated with Yttrium-90 Microspheres, Dose Volumetrics on Post-Treatment Bremsstrahlung SPECT/CT Predict Clinical Outcomes.

In transarterial radioembolization (TARE) of hepatocellular carcinoma (HCC) with Yttrium-90 (Y-90) microspheres, recent studies correlate dosimetry from bremsstrahlung single photon emission tomography (SPECT/CT) with treatment outcomes; however, these studies focus on measures of central tendency rather than volumetric coverage metrics commonly used in radiation oncology. We hypothesized that three-dimensional (3D) isodose coverage of gross tumor volume (GTV) is the driving factor in HCC treatment response to TARE and is best assessed using advanced dosimetry techniques applied to nuclear imaging of actual Y-90 biodistribution. We reviewed 51 lobar TARE Y-90 treatments of 43 HCC patients. Dose prescriptions were 120 Gy for TheraSpheres and 85 Gy for SIR-Spheres. All patients underwent post-TARE Y-90 bremsstrahlung SPECT/CT imaging. Commercial software was used to contour gross tumor volume (GTV) and liver on post-TARE SPECT/CT. Y-90 dose distributions were calculated using the Local Deposition Model based on post-TARE SPECT/CT activity maps. Median gross tumor volume (GTV) dose; GTV receiving less than 100 Gy, 70 Gy and 50 Gy; minimum dose covering the hottest 70%, 95%, and 98% of the GTV (D70, D95, D98); mean dose to nontumorous liver, and disease burden (GTV/liver volume) were obtained. Clinical outcomes were collected for all patients by chart and imaging review. HCC treatment response was assessed according to the modified response criteria in solid tumors (mRECIST) guidelines. Kaplan-Meier (KM) survival estimates and multivariate regression analyses (MVA) were performed using STATA. Median survival was 22.5 months for patients achieving objective response (OR) in targeted lesions (complete response (CR) or partial response (PR) per mRECIST) vs. 7.6 months for non-responders (NR, stable disease or disease progression per mRECIST). On MVA, the volume of underdosed tumor (GTV receiving less than 100 Gy) was the only significant dosimetric predictor for CR (p = 0.0004) and overall survival (OS, p = 0.003). All targets with less than CR (n = 39) had more than 20 cc of underdosed tumor. D70 (p = 0.038) correlated with OR, with mean D70 of 95 Gy for responders and 60 Gy for non-responders (p = 0.042). On MVA, mean dose to nontumorous liver trended toward significant association with grade 3+ toxicity (p = 0.09) and correlated with delivered activity (p < 0.001) and burden of disease (p = 0.05). Dosimetric models supplied area under the curve estimates of > 0.80 predicting CR, OR, and ≥grade 3 acute toxicity. Dosimetric parameters derived from the retrospective analysis of post-TARE Y-90 bremsstrahlung SPECT/CT after lobar treatment of HCC suggest that volumetric coverage of GTV, not a high mean or median dose, is the driving factor in treatment response and that this is best assessed through the analysis of actual Y-90 biodistribution.

Long-Term Effects of Proximal Splenic Artery Embolization on Splenic Volume and Platelet Count.

BACKGROUND: The spleen is the most commonly injured visceral organ in blunt abdominal trauma. Post-splenectomy infection risk has led to the shift toward spleen preserving procedures and splenic artery embolization (SAE) is now the treatment of choice for hemodynamically stable patients with splenic injury. This study aims to assess the long-term effect of SAE on splenic volume and platelet count. MATERIALS AND METHODS: Using CPT codes, 66 patients who underwent SAE were identified, and 14 of those who had the necessary imaging and laboratory follow-up were included in the study. Indications for SAE were portal hypertension in 8 patients, bleeding in 4 patients, and thrombocytopenia in 1, and one patient had a separate indication. Splenic volume was calculated by automated volumetric software (Aquarius, TeraRecon, Inc.). Paired t-tests were performed to compare splenic volume and platelets before and after SAE. RESULTS: Fourteen patients (7 males, 7 females) with a mean age of 51 ± 11.95 years underwent SAE and were followed by a repeat computed tomography scan at an average of 733.57 days. Nine SAEs were performed using vascular plugs, 3 using micro coils, and 2 out of that were with Gelfoam slurry, and 2 using coils only. All embolizations were technically successful with complete cessation of flow. Mean splenic volumes pre- and post-SAE were 903.5 ± 523.73 cm3 and 746.5 ± 511.95 cm3, respectively, representing a mean decrease of 8.31% compared to baseline [P = 0.346]. Minimum platelet counts (x103) pre-SAE (within 3 months) and post-SAE (2 weeks to 3 months after the procedure) were 55.79 ± 57.11 and 116 ± 145.40, respectively. The minimum platelet count showed a statistically significant mean increase of 134.92% (P = 0.033). CONCLUSIONS: The splenic volume is not altered significantly by SAE in the long term. Similarly, the platelet count is also not significantly altered at 3 months follow-up. This study, although small, suggests that SAE is a safe intervention that can preserve splenic volume and function in the long term.

Management of Patients With Gastric Varices.

Management of patients with gastric varices represents a unique challenge for clinicians. The broad range of endoscopic and endovascular techniques currently available is in stark contrast with the limited evidence available to inform the optimal management of these patients. This article describes the classification, pathophysiology, and natural history of gastric varices; summarizes the available evidence regarding medical, endoscopic, and endovascular management of gastric varices; and provides recommendations on how to integrate these options. Management of these patients ultimately requires a multidisciplinary approach involving hepatologists, therapeutic endoscopists, and interventional radiologists, with consideration given to patient characteristics and local expertise.

Arteriovenous fistulas for hemodialysis: Brief review and current problems.

The number of people worldwide living with end-stage renal disease is increasing. Arteriovenous fistulas are the preferred method of vascular access in patients who will require hemodialysis. As the number of patients with arteriovenous fistulas grows, the role of physicians who intervene who maintain and salvage these fistulas will grow in importance. This review aims to familiarize practitioners with the rationale for arteriovenous fistula creation, the detection of fistula dysfunction, and the state of the art on fistula maintenance and preservation. Current controversies are briefly reviewed.

Benign Prostatic Hyperplasia: A Brief Overview of Pathogenesis, Diagnosis, and Current State of Therapy.

As prostatic artery embolization is assuming an increasingly important role in the management of benign prostatic hyperplasia, it is important for the practicing interventional radiologist to have a deep understanding of all aspects of the disease process and the available treatment options. This paper provides a comprehensive overview of the pathophysiology, diagnosis and management options for benign prostatic hyperplasia with an emphasis on the surgical and medical treatments.

Liquid Nitrogen-Based Cryoablation in In Vivo Porcine Tissue: A Pilot Study.

INTRODUCTION: Liquid nitrogen-based cryoablation induces freezing evenly throughout the probe tip surface, resulting in larger ablation volumes and faster treatment times. The purpose of this preliminary investigation is to determine the efficacy of the liquid nitrogen-based Visica2 Cryoablation System (Sanarus Technologies, Pleasanton, CA) in in vivo porcine kidney, liver, and fibro-fatty tissue. METHODS: Ablations were performed under ultrasound guidance in 4 Yorkshire pigs. The target lesion cross-section width (W) and depth (D) were 1 cm for liver (n=8), kidney (n=4), and head-neck (n=5) and 2 cm for kidney (n=4).  Expected axial length (L) of the resulting lesion is approximately 4 cm.  After three-day survival, the ablated tissue was harvested and histologically analysed. The mean width and depth were compared with the target diameter using a one-sample t-test. RESULTS: All animals survived the procedure. For the 1 cm target, mean dimensions (L x W x D) were 3.8±1.5 x 1.7±0.3 x 1.7±0.7 for liver, 3.0±0.5 x 2.0±0.4 x 1.7±0.6 for kidney, and 3.3±0.8 x 1.8±0.4 x 1.8±0.4 for head-neck.  Mean width and depth were significantly greater than desired dimension.  For the 2 cm target, mean dimensions were 3.2±0.5 x 3.1±0.8 x 1.9±0.7.  Mean width and depth were not significantly different to desired target. CONCLUSION: Our preliminary results show that the Visica2 liquid nitrogen-based cryoablation system can efficiently and reproducibly create ablation volumes in liver, kidney, and fibro-fatty tissue within 4 minutes and 12 minutes for 1cm and 2cm targeted diameters, respectively. Further investigation is necessary to determine the optimal freeze-thaw-freeze protocol for larger ablation volumes.
.

Embolization of hemorrhage from a ruptured hepatocellular carcinoma via the false lumen of an aortic dissection using transradial access.

BACKGROUND AND AIMS: Transcatheter arterial embolization (TAE) has been repeatedly shown as an effective method of controlling acute hemorrhage. Arterial access for TAE in the emergent setting is typically trans-femoral, though other routes are routinely used. The presence of abnormal vasculature such as an aortic dissection increases the difficulty of TAE. CASE REPORT: This report details a case of acute hemorrhage likely from a ruptured hepatocellular carcinoma in which the celiac artery originated from the false lumen of a type B aortic dissection. CONCLUSION: The false lumen was catheterized via left radial artery access and the bleeding hepatic arterial branch was successfully embolized.

Pelvic Trauma: factors predicting arterial hemorrhage and the role of Angiography and preperitoneal pelvic packing.

OBJECTIVES: (1) To identify the factors predicting arterial extravasation in pelvic trauma and (2) to assess the efficacy of preperitoneal pelvic packing (PPP) in controlling arterial hemorrhage. METHODS: Institutional review board approved the retrospective study of 139 consecutive pelvic trauma patients who underwent angiographic intervention with or without prior PPP between January 2011 and December 2016. Patient demographics and presenting characteristics were recorded. Both groups of patients were combined for analysis of predictors for arterial extravasation using univariate logistic regression followed by multivariate logistic regression. Significance level was defined as p < 0.05. RESULTS: Forty-nine out of 139 patients had PPP prior to pelvic angiogram. Embolization was performed in 85 (61.2%) patients and the technical and clinical success rate was 100%. Sixty-nine (49.7%) patients had unstable Young-Burgess (Y&B) type fractures, of which 58% had arterial hemorrhage compared with 38.6% of those with stable Y&B fractures (p = 0.02). Of the patients who had PPP prior to angiogram, 28(57.1%) continued to have arterial extravasation on subsequent angiography. Unstable Y&B type fractures are independent predictors of arterial hemorrhage (OR 2.3, 95%CI 1.1 to 4.7, p = 0.02). CONCLUSION: Unstable Y&B type pelvic fractures are predictors of arterial extravasation. PPP alone is not effective for arterial hemorrhage control in pelvic trauma. Angiographic intervention remains a minimally invasive and definitive treatment of arterial hemorrhage from pelvic trauma. KEY POINTS: • Unstable Young-Burgess pelvic fractures are predictors of arterial hemorrhage in pelvic trauma. • Pelvic angiography and embolization should precede PPP wherever feasible.

Utilization of a Modified Roux-en-Y Anastomosis as an Access point for Percutaneous Transjejunal Cholangioplasty of Recurrent Biliary Strictures.

INTRODUCTION: Biliary duct injuries pose a significant management challenge due to the propensity for recurrent biliary strictures. Development of a modified Roux-en-Y hepaticojejunostomy known as a Hutson-Russell Pouch (HRP) provides a point of entry for repetitive access to the biliary tree. We aim to highlight the effectiveness of using the HRP as an access point for the long-term management of anastomotic and distal biliary strictures, thereby showcasing the value in potential widespread adoption of this modification to a standard surgical procedure. MATERIALS AND METHODS: IRB-approved retrospective study of 36 patients (10 M, 26 F; mean age 55.19 ± 13.94; 15-83) underwent a total of 110 transjejunal cholangiograms. Indications for cholangiogram included cholangitis (n = 38), surveillance (n = 36), and elevated liver enzymes (n = 36). Technical success was defined by the ability to access and intervene in the biliary tree via HRP access. In case of stenosis, the ability to successfully dilate (< 30%) residual stenosis was considered a technically successful procedure. Clinical success was defined by normalization of the liver function tests or resolution of cholangitis. RESULTS: Technical success was achieved in 83/110 (75.45%) of the cases, and clinical success was achieved in 102/110 (98.2%). Transhepatic access was needed in 27/110 (24.5%) of the cases. Interventions performed included balloon cholangioplasty in 104/110 (94.5%), biliary stone removal in 2/110 (1.8%), biliary stent placement in 2/110 (1.8%), and biliary drain placement in 4/110 (3.6%). There were a total of 9/110 complications (8.2%). CONCLUSION: The HRP was an effective access point in the management of recurrent benign biliary strictures in this cohort.

Hemosuccus pancreaticus from superior mesenteric artery pseudoaneurysm within perceived pancreatic mass.

Bleeding from the pancreatic duct is a rare source of gastrointestinal hemorrhage and is referred to as hemosuccus pancreaticus. Often a result of pseudoaneurysm formation from chronic pancreatitis, hemosuccus pancreaticus is a difficult diagnosis due to its peculiar clinical presentation. This is a case of a 51-year-old male with a history of chronic pancreatitis, who initially presented with a pancreatic mass found on CT scan. The mass was found to be inconclusive for malignancy on endoscopic ultrasound-guided fine needle aspiration. The patient subsequently was lost to follow-up and returned with melena and evidence of a superior mesenteric pseudoaneurysm in the previous mass on CT angiography. The pseudoaneurysm was successfully treated with endovascular embolization. Diagnosis of hemosuccus pancreaticus can be challenging due to the intermittent nature of hemorrhage and the variable clinical presentation-which initially appeared as a pancreatic neoplasm in our patient. Repeat imaging and angiography are invaluable for both the diagnosis and treatment of gastrointestinal bleeding from an unknown source in the setting of chronic pancreatitis.

Clinical predictors of arterial extravasation, rebleeding and mortality following angiographic interventions in gastrointestinal bleeding.

BACKGROUND AND AIMS: The aim of this study was to identify clinical and imaging predictors of arterial extravasation, post embolization rebleeding and 30-day mortality in gastrointestinal (GI) bleeding. METHOD: This retrospective study included 114 patients who underwent angiography for upper or lower GI bleeding. Multivariate logistic regression was used to identify clinical and imaging predictors. RESULTS: Angiography demonstrated arterial extravasation in 22 patients (19%) and embolization was performed in 48 (42%) patients including prophylactic embolization in 26 (56%). Fall in hemoglobin level from baseline was an independent predictor of arterial extravasation with 65% increased odds for every unit drop (OR 1.65, 95%CI 1.13-2.40, p=0.01). Age <60 years was a negative predictor of rebleed within 30-days (OR 0.94, 95%CI 0.89-1.00, p=0.04). Patients with a history of malignancy were more likely to rebleed (OR 4.4, 95%CI 1.06-18.36, p=0.04). Hemodynamic instability prior to angiography (OR 13.22, 95%CI 1.65-106.07, p=0.02), history of malignancy (OR 1.36, 95%CI 1.49-10.49, p=0.01), number of units of platelets transfused (OR 1.42, 95%CI 1.02-1.97, p=0.04) and rebleed after angiography (OR 46.8, 95%CI 4.80-456.14, p<0.01) were predictors of 30-day mortality. Prophylactic embolization was not a predictor of rebleed or 30-day mortality. CONCLUSIONS: This paper identified important clinical predictors of arterial extravasation, rebleed and 30-day mortality in GI bleedings, which will assist in patient selection and help to improve the overall angiographic management of GI bleeding.

Percutaneous Retrieval of IVC Filters With Struts Penetrating the Vertebral Body.

INTRODUCTION: Inferior vena cava (IVC) filter penetration of the caval wall is a well-documented complication. Less frequently, the struts of an IVC filter can penetrate a vertebral body that can lead to symptoms of abdominal pain. Vertebral penetration poses a management challenge, and characteristics for successful endovascular retrieval of such filters has not been reported. CASE DESCRIPTION: We present 2 cases of IVC filters with vertebral body penetration that were successfully retrieved through an endovascular approach. On preprocedure computed tomography, both patients had a small zone of osteolysis surrounding the penetrated struts into the vertebral body. The procedures were done via right internal jugular access using an Ensnare device. In one of the cases, the hangman technique was used to release the filter apex from the vessel wall. Both filters were able to be retrieved without using excessive force, follow-up venacavograms showed no sign of extravasation, and no postprocedure complications developed. DISCUSSION: Preprocedure CT imaging is essential prior to IVC filter removal if vertebral penetration is suspected. The zone of osteolysis seen around the struts in both cases are likely the result of constant cardiorespiratory motion of the filter. Based on the fact that in both cases the filter legs were able to be disengaged from the vertebral body without the use of excessive force, we hypothesize that if a zone of osteolysis surrounding the struts can be confirmed on preprocedural CT, the filter removal can be safely attempted by the standard percutaneous endovascular approach.

Colorectal Liver Metastasis: Overview of Treatment Paradigm Highlighting the Role of Ablation.

OBJECTIVE: The objective of this article is to discuss the current treatment options for colorectal cancer (CRC) liver metastases and the role of ablation. CONCLUSION: A randomized control trial of ablation combined with chemotherapy showed improved overall survival compared with chemotherapy alone. Local recurrence rates are comparable to those associated with resection when ablative margins of more than 5 mm are achieved and target lesions are smaller than 3 cm. In patients with unresectable disease, ablation for curative intent should be considered.

Ultrasound-Assisted Catheter-Directed Thrombolysis for Submassive Pulmonary Embolism.

PURPOSE: Catheter-directed thrombolysis (CDT) is a relatively new therapy for pulmonary embolism that achieves the superior clot resolution compared to systemic thrombolysis while avoiding the high bleeding risk intrinsically associated with that therapy. In order to examine the efficacy and safety of CDT, we conducted a retrospective cohort study of patients undergoing ultrasound-assisted CDT at our institution. METHODS: The charts of 30 consecutive patients who underwent CDT as a treatment of pulmonary embolism at our institution were reviewed. Risk factors for bleeding during thrombolysis were noted. Indicators of the right heart strain on computed tomography and echocardiogram, as well as the degree of pulmonary vascular obstruction, were recorded before and after CDT. Thirty-day mortality and occurrence of bleeding events were recorded. RESULTS: Nine (30%) patients had 3 or more minor contraindications to thrombolysis and 14 (47%) had major surgery in the month prior to CDT. Right ventricular systolic pressure and vascular obstruction decreased significantly after CDT. There was a significant decrease in the proportion of patients with right ventricular dilation or hypokinesis. Decrease in pulmonary vascular obstruction was associated with nadir of fibrinogen level. No patients experienced major or moderate bleeding attributed to CDT. CONCLUSION: Catheter-directed thrombolysis is an effective therapy in rapidly alleviating the right heart strain that is associated with increased mortality and long-term morbidity in patients with pulmonary embolism with minimal bleeding risk. Catheter-directed thrombolysis is a safe alternative to systemic thrombolysis in patients with risk factors for bleeding such as prior surgery. Future studies should examine the safety of CDT in patients with contraindications to systemic thrombolysis.

Bowel Obstruction: Decompressive Gastrostomies and Cecostomies.

Over the past 30 years, image-guided placement of gastrostomies and cecostomies for gastrointestinal decompression has developed into a safe and effective treatment for symptomatic bowel obstruction. Gastrostomies and cecostomies relieve patient symptoms, can prevent serious complications such as colonic perforation, and may bridge patients to more definitive treatment for the underlying cause of obstruction. This article will review the history of decompressive gastrostomies and cecostomies as well as the indications, contraindications, technique, complications, and outcomes of these procedures.

Transjugular intrahepatic portosystemic shunt for chylous ascites in a patient with recurrent cirrhosis following liver transplantation.

Chylous ascites (CA) is the extravasation of lipid-rich lymphatic fluid into the peritoneal space following trauma or obstruction of the lymphatic system. Refractory cases of cirrhosis-related CA may be amendable to transjugular intrahepatic portosystemic shunting (TIPS). We present a case of TIPS in the setting of refractory CA secondary to cirrhosis of a transplanted liver graft. Following TIPS, the patient reported immediate improvement in abdominal pain and no longer requires paracentesis. Our case suggests TIPS to be a safe and effective treatment option for CA in liver transplant patients with cirrhosis.