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At least 73 records · Page 4

Incidence and Consequence of Nontarget Embolization Following Bland Hepatic Arterial Embolization

Purpose: Estimate the incidence of nontarget embolization (NTE) as identified on immediate post-hepatic artery embolization CT. Materials and Methods: Two hundred hepatic embolizations performed with particles alone (bland embolization) in 147 patients between August 16, 2013 and August 26, 2014 with immediate post-procedure CT were retrospectively reviewed. Arterial anatomy, vessels treated, imaging findings of NTE, patient demographics, length of hospital stay following embolization, and procedure-related complications were recorded. The data were analyzed using two-sided t-tests and chi-squared tests. Results: Evidence of NTE was seen on post-procedure CT in 64 of 200 cases (64/200, 32%). Six organs were affected, with 69 discrete sites in 64 patients. The majority (49/69, 71.0%) involved the gallbladder. The mean length of hospital stay (LOS) for patients with and without NTE was 2.9 ± 1.5 nights (range 1–7) and 2.9 ± 2.3 nights (range 0–21), respectively (P = 0.81). NTE was more common following embolization of replaced or accessory hepatic vessels. There were three complications in the NTE group (3/64, 4.7%) following the embolization procedure, one of which was cholecystitis directly related to NTE. The other two were one incidence each of contrast-induced nephropathy and pneumonia. In the group without NTE, seven complications occurred (7/136, 5.1%, P = 0.889), including one death resulting from hepatic failure, two gastrointestinal bleeds, two hepatic abscesses, flash pulmonary edema, and pancreatitis. Conclusion: Unanticipated NTE is not uncommon after bland hepatic artery embolization, particularly after treating accessory or replaced vessels, but does not increase complications or LOS. Level of Evidence: Level 2b, Retrospective Cohort.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Role of sphingosine‐1‐phosphate receptors in vascular injury of inflammatory bowel disease

Abstract Sphingosine‐1‐phosphate receptors (S1PRs) have an impact on the intestinal inflammation of inflammatory bowel disease (IBD) by regulating lymphocyte migration and differentiation. S1PR modulators as an emerging therapeutic approach are being investigated for the treatment of IBD. However, the role of S1PRs in intestinal vessels has not drawn much attention. Intestinal vascular damage is one of the major pathophysiological features of IBD, characterized by increased vascular density and impaired barrier function. S1PRs have pleiotropic effects on vascular endothelial cells, including proliferation, migration, angiogenesis and barrier homeostasis. Mounting evidence shows that S1PRs are abnormally expressed on intestinal vascular endothelial cells in IBD. Unexpectedly, S1PR modulators may damage intestinal vasculature, for example increase intestinal bleeding; therefore, S1PRs are thought to be involved in the regulation of intestinal vascular function in IBD. However, little is understood about how S1PRs regulate intestinal vascular function and participate in the initiation and progression of IBD. In this review, we summarize the pathogenic role of S1PRs in and the underlying mechanisms behind the intestinal vascular injury in IBD in order for improving IBD practice including S1PR‐targeted therapies.

Wang, Xuewen↗

The utility of ultrasound guidance in transjugular liver biopsy: our experience

Purpose: To demonstrate the utility of ultrasound (US) guidance in improving the safety and efficacy of transjugular liver biopsy (TJLB) by analyzing all the TJLBs performed by us in the last 4 years. Materials and methods: Forty-seven patients who underwent TJLB in the last 4 years in our two centers were retrospectively analyzed. US guidance was used for all but for one patient during the two crucial steps of the procedure—for internal jugular vein (IJV) access and during the parenchymal biopsy. Biopsies were obtained under real-time sonographic guidance from the right lobe after confirming an adequate room for needle throw without breaching the liver capsule or any major hilar structures. Post-procedure complications, tissue yield, and histopathological adequacy of samples were analyzed. Results: Overall technical success rate was 100%. No major complications were found where ultrasound-assisted TJLB (uTJLB) was performed. One patient who underwent non-US guided TJLB had an event of a capsular breach and intra-peritoneal hemorrhage requiring coil embolization. Samples were of adequate dimension. Histopathological positivity was 100%. The overall complication rate for uTJLB was 4.7% which was due to minor complications in two patients. Conclusions: Addition of US unit to the angiographic suite is effortless and Interventional Radiologists being already skilled in US can easily implement this simple yet valuable modification to conventional TJLB procedures. Our experience on uTJLB further emphasizes the role of US guidance in improving the procedural success rate, safety profile, and efficacy in the histopathological outcome of TJLB in all patients irrespective of age and disease burden.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Fusion Imaging Reduces Radiation and Contrast Medium Exposure During Endovascular Revascularization of Iliac Steno-Occlusive Disease

Introduction: To evaluate feasibility, safety and efficacy of fusion imaging in order to guide endovascular revascularization of iliac steno-occlusive disease. Materials and Methods: Retrospectively, we identified twenty-six patients (20 male, mean age 63 ± 8y; Rutherford II-V) who underwent revascularization of a chronic total occlusion (n = 6; 23%) or severe stenosis (n = 20; 77%) of the common and/or external iliac artery. Median lesion length was 33 mm (IQR 20–60). In one group of patients (NEW; n = 11), fusion imaging with 2-D/3-D registration was used to guide revascularization. No baseline digital subtraction angiography (DSA) had been acquired in these patients. In another group of patients (OLD; n = 15), no fusion imaging had been utilized and at least one DSA run had been performed to guide the procedure. In both groups, final DSA of the treated lesions was performed. Number of DSA runs, radiation and contrast medium exposure, technical success (residual stenosis < 30%) and complications were analyzed. Results: Median DSA runs needed in OLD for guidance were n = 2 (IQR 2–3) and in NEW n = 0 (IQR 0–0; p = 0.001). Compared to OLD, median dose area product (DAP) was reduced by 17,118 mGy*cm{sup 2} (IQR 10,407–23,614; p = 0.016) if fusion imaging guidance had been used (NEW). Based on the median DAP of the final angiogram in NEW, median DAP reduction was 6007 mGy*cm{sup 2} (IQR 5012–16,105; p = 0.1). Median total contrast medium volume injected in NEW was 45 ml (IQR 30–90) and in OLD 120 ml (IQR 100–140; p = 0.001). Technical success was 100% for both groups. In 1/27 patients (3.7%) a minor complication (embolism) occurred. Conclusion: Fusion imaging proved to be feasible as well as safe and significantly reduces radiation and contrast medium exposure during endovascular revascularization of iliac steno-occlusive disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Efficacy of Preoperative Transcatheter Arterial Embolization for Nasopharyngeal Angiofibroma: A Comparative Study

ObjectiveThis study aimed to retrospectively evaluate the efficacy and safety of preoperative transcatheter arterial embolization (pTAE) for treating nasopharyngeal angiofibroma (NPAF).MethodsSeventy-four NPAF patients were hospitalized for elective surgical treatment with pTAE (pTAE group, n = 32) or surgical treatment alone (non-pTAE group, n = 42) between January 1990 and December 2013. The following outcome measures were retrospectively analyzed and compared: intraoperative bleeding volume, surgery time (ST), duration of postoperative hospital stay (PHS), and disease recurrence.ResultsAmong Radkowski stage I patients, those in pTAE group had a slightly higher but not significant bleeding volume than patients in non-pTAE group (344 ± 407 vs. 248 ± 219 mL, P = 0.899); among stage II/III patients, however, patients in pTAE group showed a significantly lower bleeding volume than patients in non-pTAE group (stage II, 829 ± 519 vs. 1339 ± 767 mL, P = 0.035; stage III, 1267 ± 592 vs. 2125 ± 479 mL, P = 0.024). The two groups presented comparable OTs, PHSs, and rates of frontal recurrence (all P>0.05).ConclusionspTAE significantly reduces intraoperative bleeding in NPAF patients with Radkowski stage II/III disease, but offers no additional benefits regarding ST, PHS, or recurrence.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Percutaneous Cementoplasty for Kienbock’s Disease

Kienböck disease typically presents with wrist pain, swelling, restricted range of motion, and difficulty in performing activities of daily living. Because the etiology and evolution of disease remain unclear, broad ranges of treatments have been designed. Percutaneous cementoplasty is expanding its role for managing painful bone metastases outside the spine. We can draw a parallel between lytic tumoral lesions and Kienbock’s disease. Increasing the strength and rigidity of lunate with cementoplasty can prevent it from collapse, relieve the symptoms associated with the process of avascular necrosis, and increase the wrist range of motion. We report the case of 30-year-old man with a painful stage IIIA Kienböck disease who underwent percutaneous cementoplasty and experienced immediate effective pain relief and recovery of wrist mobility.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Vascular endothelial growth factor receptor-1 (FLT1) interactions with amyloid-beta in Alzheimer’s disease: A putative biomarker of amyloid-induced vascular damage

We have identified FLT1 as a protein that changes during Alzheimer's disease (AD) whereby higher brain protein levels are associated with more amyloid, more tau, and faster longitudinal cognitive decline. Given FLT1's role in angiogenesis and immune activation, we hypothesized that FLT1 is upregulated in response to amyloid pathology, driving a vascular-immune cascade resulting in neurodegeneration and cognitive decline. We sought to determine (1) if in vivo FLT1 levels (CSF and plasma) associate with biomarkers of AD neuropathology or differ between diagnostic staging in an aged cohort enriched for early disease, and (2) whether FLT1 expression interacts with amyloid on downstream outcomes, such as phosphorylated tau levels and cognitive performance. Additionally, we sought to replicate FLT1 interactions in the brain. The results showed that higher levels of FLT1 in CSF and post-mortem brain tissue related to increased tau, particularly among amyloid positive individuals. These analyses help clarify the potential utility of FLT1 as a biomarker among individuals with evidence of brain amyloidosis.

60 APPLIED LIFE SCIENCES↗

Percutaneous Image-Guided Cryoablation of Challenging Mediastinal Lesions Using Large-Volume Hydrodissection: Technical Considerations and Outcomes

ObjectiveThis study was designed to describe the technique of percutaneous image-guided cryoablation with large-volume hydrodissection for the treatment of challenging mediastinal lesions.MethodsBetween March 2014 and June 2015, three patients (mean age 62.7 years) with four neoplastic anterior mediastinal lesions underwent five cryoablation procedures using large-volume hydrodissection. Procedures were performed under general anaesthesia using CT guidance. Lesion characteristics, hydrodissection and cryoablation data, technical success, complications, and clinical outcomes were assessed using retrospective chart review.ResultsLesions (mean size 2.7 cm; range 2–4.3 cm) were in contact with great vessels (n = 13), trachea (n = 3), and mediastinal nerves (n = 6). Hydrodissection was performed intercostally (n = 4), suprasternally (n = 2), transsternally (n = 1), or via the sternoclavicular joint (n = 1) using 1–3 spinal needles over 13.4 (range 7–26) minutes; 450 ml of dilute contrast was injected (range 300–600 ml) and increased mean lesion-collateral structure distance from 1.9 to 7.7 mm. Vulnerable mediastinal nerves were identified in four of five procedures. Technical success was 100 %, with one immediate complication (recurrent laryngeal nerve injury). Mean follow-up period was 15 months. One lesion demonstrated residual disease on restaging PET-CT and was retreated to achieve complete ablation. At last follow-up, two patients remained disease-free, and one patient developed distant disease after 1 year without local recurrence.ConclusionsCryoablation using large-volume hydrodissection is a feasible technique, enabling safe and effective treatment of challenging mediastinal lesions.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Review of the Clinical Evidence for the Use of DEBIRI in the Treatment of Colorectal Metastatic Disease

Colorectal cancer is a common malignancy that most commonly metastasizes to the liver. There has been considerable effort in developing new treatment options for these patients. One method that has been developed for the treatment of colorectal metastases to the liver is irinotecan-loaded drug-eluting bead (DEBIRI) embolization. This article reviews the current literature on DEBIRI and discusses the state of current knowledge and possible areas of future investigation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Myocardial Infarction as a Complication of Bronchial Artery Embolization

Bronchial artery embolization is now a common treatment for massive pulmonary hemoptysis if flexible bronchoscopy at the bedside failed to control the bleeding. Complications of this technique range from benign chest pain to devastating neurological impairments. We report the case of a 41-year-old man who developed an ST elevation myocardial infarction during bronchial artery embolization, presumably because of coronary embolism by injected particles. In this patient who had no previously known coronary artery disease, we retrospectively found a communication between the left bronchial artery and the circumflex coronary artery. This fistula was not visible on the initial angiographic view and likely opened because of the hemodynamic changes resulting from the embolization. This case advocates for careful search for bronchial-to-coronary arterial fistulas and the need for repeated angiographic views during embolization procedures.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Use of Suture-Mediated Closure Device in Percutaneous Direct Carotid Puncture During Chimney-Thoracic Endovascular Aortic Repair

BackgroundInsertion of a carotid chimney graft during thoracic endovascular aortic repair (Ch-TEVAR) is a recognized technique to extend the proximal landing zone into the aortic arch in the treatment of thoracic aortic disease. Conventional technique requires surgical exposure of the carotid artery for insertion of the carotid chimney graft.MethodologyWe describe our experience in the use of a suture-mediated closure device in percutaneous Ch-TEVAR in four patients.ResultsSuccessful hemostasis was achieved in all four patients. No complications related to the carotid puncture were recorded.ConclusionWe conclude that using suture-mediated closure device for carotid closure appears feasible and deserves further studies as a potential alternative to conventional surgical approach.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Prostate Cancer Radiation Therapy and Risk of Thromboembolic Events

Purpose: To investigate the risk of thromboembolic disease (TED) after radiation therapy (RT) with curative intent for prostate cancer (PCa). Patients and Methods: We identified all men who received RT as curative treatment (n=9410) and grouped according to external beam RT (EBRT) or brachytherapy (BT). By comparing with an age- and county-matched comparison cohort of PCa-free men (n=46,826), we investigated risk of TED after RT using Cox proportional hazard regression models. The model was adjusted for tumor characteristics, demographics, comorbidities, PCa treatments, and known risk factors of TED, such as recent surgery and disease progression. Results: Between 2006 and 2013, 6232 men with PCa received EBRT, and 3178 underwent BT. A statistically significant association was found between EBRT and BT and risk of pulmonary embolism in the crude analysis. However, upon adjusting for known TED risk factors these associations disappeared. No significant associations were found between BT or EBRT and deep venous thrombosis. Conclusion: Curative RT for prostate cancer using contemporary methodologies was not associated with an increased risk of TED.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

The Introduction of an Undergraduate Interventional Radiology (IR) Curriculum: Impact on Medical Student Knowledge and Interest in IR

IntroductionInterventional radiology (IR) plays a vital role in modern medicine, with increasing demand for services, but with a shortage of experienced interventionalists. The aim of this study was to determine the impact of a recently introduced IR curriculum on perception, knowledge, and interest of medical students regarding various aspects of IR.MethodsIn 2014, an anonymous web-based questionnaire was sent to 309 4th year medical students in a single institution within an EU country, both before and after delivery of a 10-h IR teaching curriculum.ResultsSeventy-six percent (236/309) of the respondents participated in the pre-IR module survey, while 50 % (157/309) responded to the post-IR module survey. While 62 % (147/236) of the respondents reported poor or no knowledge of IR compared to other medical disciplines in the pre-IR module survey, this decreased to 17 % (27/157) in the post-IR module survey. The correct responses regarding knowledge of selected IR procedures improved from 70 to 94 % for venous access, 78 to 99 % for uterine fibroid embolization, 75 to 97 % for GI bleeding embolization, 60 to 92 % for trauma embolization, 71 to 92 % for tumor ablation, and 81 to 94 % for angioplasty and stenting in peripheral arterial disease. With regard to knowledge of IR clinical roles, responses improved from 42 to 59 % for outpatient clinic review of patients and having inpatient beds, 63–76 % for direct patient consultation, and 43–60 % for having regular ward rounds. The number of students who would consider a career in IR increased from 60 to 73 %.ConclusionDelivering an undergraduate IR curriculum increased the knowledge and understanding of various aspects of IR and also the general enthusiasm for pursuing this specialty as a future career choice.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Correlation between SACE (Subjective Angiographic Chemoembolization Endpoint) score and tumor response and its impact on survival after DEB-TACE in patients with hepatocellular carcinoma

Purpose: To asses angiographic and computed tomographic success criteria during and after transcatheter arterial drug-eluting bead chemoembolization (DEB-TACE) in patients with hepatocellular carcinoma (HCC) and its impact on progression-free survival (PFS) and overall survival (OS). Methods: In this retrospective single-center study, 50 patients with unresectable HCC having undergone DEB-TACE from January 2010 to July 2015 were assessed. The angiographic endpoint was classified by Subjective Angiographic Chemoembolization Endpoint (SACE) scale. Relative tumor density in arterial (D{sub Art}) and portal venous phase (D{sub PV}) computed tomography post- versus pre-DEB-TACE were calculated, respectively. Tumor response according to modified Response Criteria in Solid Tumors (mRECIST) was assessed. Univariate Kaplan–Meier and Cox regression analysis were carried out. Results: SACE scores I, II, III, and IV were found in 1 (2%), 20 (40%), 15 (30%), and 14 (28%) patients, respectively. Median OS and PFS were 14.2 and 5.5 months, respectively. Death rates at 6 months, 1 year and 2 years were 24%, 38%, and 52%, respectively. SACE score during DEB-TACE significantly correlated with local and overall mRECIST results (local: p < 0.001, r = 0.49, overall: p = 0.042, r = 0.29) and inversely correlated with D{sub PV} (p = 0.005, r = − 0.40). In univariate analysis, progressive disease (PD) according to mRECIST and increase of D{sub Art} and D{sub PV} were associated with significantly shorter PFS. Modified RECIST independently predicted OS (hazard ratio for complete remission vs. PD = 0.15, 95% confidence interval 0.03–0.68, p = 0.014). Conclusions: A direct impact of SACE on PFS or OS could not be shown. However, SACE significantly correlated with local and overall mRECIST tumor response that again significantly predicted OS. We therefore postulate an indirect impact of SACE on OS. Consequently, complete embolization should be attempted.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Removal of Retrievable Self-Expandable Metallic Tracheobronchial Stents: An 18-Year Experience in a Single Center

PurposeThe purpose of the study was to retrospectively evaluate the technical outcomes of removal of retrievable self-expandable metallic stents (REMSs) and identify predictors of technical failure in 81 patients with benign and malignant tracheobronchial strictures.Materials and MethodsA total of 98 REMSs were removed under fluoroscopic guidance in 81 patients with benign (n = 48) or malignant (n = 33) tracheobronchial strictures. Primary and secondary technical success rates and complication rate were evaluated. Technical outcomes with regard to underlying diseases were also evaluated. Logistic regression models were constructed to identify predictors of primary technical success.ResultsPrimary and secondary technical success rates were 86.7 and 94.9 %, respectively. Stent removal-related complication rate was 7.1 % (7/98) and all were bleeding after stent removal. All bleeding complications were minor and managed conservatively. Primary technical success rate for benign strictures was significantly lower compared with that for malignant strictures (80.9 vs. 97.1 %, P = 0.029), but secondary technical success rate (93.7 vs. 97.1 %, P = 0.652) did not differ between the two groups. Granulation tissue formation was identified as an independent predictor of primary technical success (odds ratio 0.249, 95 % CI 0.071–0.874, P = 0.030).ConclusionRemoval of REMSs in patients with benign and malignant tracheobronchial strictures is safe and technically feasible. Bronchoscopic guidance may be required when the removal using a hook wire fails. The presence of granulation tissue was the negative predictor of primary technical success.

62 RADIOLOGY AND NUCLEAR MEDICINE↗