Technical considerations of endovascular management of true visceral artery aneurysms.

BACKGROUND: True visceral artery aneurysms are potentially complex to treat but with advances in technology and increasing interventional radiology expertise over the past decade are now increasingly the domain of the interventional radiologist. BODY: The interventional approach is based on localization of the aneurysm and identification of the anatomical determinants to treat these lesions to prevent aneurysm rupture. Several different endovascular techniques are available and should be selected carefully, dependent on the aneurysm morphology. Standard endovascular treatment options include stent-graft placement and trans-arterial embolisation. Different strategies are divided into parent artery preservation and parent artery sacrifice techniques. Endovascular device innovations now include multilayer flow-diverting stents, double-layer micromesh stents, double-lumen balloons and microvascular plugs and are also associated with high rates of technical success. CONCLUSION: Complex techniques such as stent-assisted coiling and balloon-remodeling techniques are useful techniques and require advanced embolisation skills and are further described.

Developing day-case units: imperative for optimal patient care in interventional radiology.

As interventional radiology (IR) treatments have evolved, they have become less invasive, enabling rapid recovery, which expedites ambulation and promotes same-day discharge. As a result of this, a significant proportion of IR elective work can be provided using a day-case service model. Reconfiguration of IR services to increase day-case procedures using a dedicated IR day-case unit (RDU) to facilitate the passage of patients is vital to ensure best medical practice. The aim of this review is to discuss the benefits of day-case IR procedures, the optimal structure of an RDU, and to inform radiologists how to introduce and/or improve day-case IR services in their IR practice.

Access to beds for interventional radiology patients: improving patient care.

This review describes the rationale in support of admitting rights for interventional radiologists and presents options for the management of interventional radiology (IR) inpatients. The manuscript also discusses wider aspects of IR involvement in inpatient treatment, such as income and funding for IR services, and the implications for IR as a clinical specialty.

Adipose tissue dysfunction in obese horses with equine metabolic syndrome.

BACKGROUND: Obesity is a common feature of equine metabolic syndrome (EMS). In other species, obese adipose tissue shows pathological features such as adipocyte hypertrophy, fibrosis, inflammation and impaired insulin signalling all of which contribute to whole body insulin dysregulation. Such adipose tissue dysfunction has not been investigated in horses. OBJECTIVES: To determine if obese horses with EMS have adipose tissue dysfunction characterised by adipocyte hypertrophy, fibrosis, inflammation and altered insulin signalling. STUDY DESIGN: Cross-sectional post-mortem study. METHODS: Samples of peri-renal (visceral) and retroperitoneal adipose tissue were obtained at post-mortem from healthy horses (n = 9) and horses with EMS (n = 6). Samples were analysed to determine average adipocyte size, fibrotic content and expression of inflammatory and insulin signalling genes. RESULTS: Horses with metabolic syndrome showed marked adipocyte hypertrophy and increased expression of adipokines (leptin) and inflammatory cytokines (TNFα, IL1ß and CCL2) in both adipose tissue depots compared to healthy horses. There were no differences in fibrosis or expression of genes relating to insulin signalling between the groups. MAIN LIMITATIONS: Cases used in this study had advanced EMS and may represent the end stage of the condition; the design of the study is such that we were unable to relate the identified adipose tissue dysfunction to whole body insulin dysregulation. CONCLUSIONS: Horses with obesity and EMS have significant dysfunction of the peri-renal and retroperitoneal adipose tissue that may contribute to whole body insulin dysregulation.

Percutaneous interventions following endovascular aneurysm sac sealing: Endoleak embolization and limb-related adverse events.

The Nellix endovascular aneurysm sealing system is a novel alternative to conventional endovascular aneurysm repair for aortic aneurysm management using paired balloon-expandable endografts supported by polymer-filled endobags to achieve sealing and anatomic fixation. Part of the promise of endovascular aneurysm sealing is increased resistance to lateral and longitudinal forces and a potential for reduced rates of device-related failures, particularly endoleaks. Initial efficacy data on this device are encouraging, but our knowledge of its associated complications and their management is limited. Reported adverse events include Type I and II endoleaks, graft stenosis, and occlusion. The aim of this article was to review the early experience of endovascular aneurysm sealing, focusing on the incidence, significance, and management of device-related complications.

Secondary interventions after endovascular aneurysm sac sealing: endoleak embolization and limb-related interventions.

The Nellix endovascular aneurysm sealing system is a novel alternative to conventional endovascular aneurysm repair for aortic aneurysm management using paired balloon expandable endografts supported by polymer-filled endobags to achieve sealing and anatomic fixation. Part of the promise of endovascular aneurysm sealing is increased resistance to lateral and longitudinal forces and thus a potential for reduced rates of device-related failures, particularly endoleaks. Initial efficacy data on this device are encouraging, but our knowledge of its associated complications and their management is limited. Reported adverse events include Type 1 and 2 endoleaks, graft stenosis and occlusion. The aim of this article is to review the early experience of endovascular aneurysm sealing focusing on the incidence, significance, and management of device-related complications.

Transiliac Paraendograft Embolisation of Type 2 Endoleak: An Alternative Approach for Endoleak Management.

Selective transarterial catheterisation and translumbar sac puncture are well established techniques for the management of significant type 2 endoleaks. We report an additional technique for endovascular access to the endoleak sac through the space between the iliac endograft and artery wall.

Treatment of equine metabolic syndrome: A clinical case series.

REASONS FOR PERFORMING STUDY: Treatment of equine metabolic syndrome (EMS) is essential to improve insulin sensitivity and reduce the risk of laminitis. Calorie restriction and increased exercise are the mainstays of treatment but there is potential for poor owner compliance. OBJECTIVES: To determine whether significant weight loss accompanied by improvements in measures of insulin sensitivity can be achieved in horses and ponies with EMS managed by their owners in their normal environment under veterinary guidance. STUDY DESIGN: Retrospective clinical case series. METHODS: Horses and ponies attending 2 university hospitals for investigation and treatment of suspected EMS were eligible for inclusion in the study. Animals underwent a clinical examination, basal and dynamic endocrine testing; those with pituitary pars intermedia dysfunction (PPID) were excluded. Owners were given individually tailored diet and exercise programmes to follow for between 3 and 6 months. After the treatment period, clinical examination and endocrine tests were repeated and results compared to the initial assessment. RESULTS: Nineteen animals were recruited to the study, 17 with a history of laminitis. All animals showed a reduction in body condition score (P<0.001) and 18/19 had a reduction in bodyweight (P<0.001) between assessments. There were significant (P<0.05) reductions in basal insulin, insulin at 45 min during a combined glucose insulin tolerance test (CGIT), time for blood glucose concentration to return to baseline during a CGIT and mean area under the glucose curve. CONCLUSIONS: A diet and exercise programme tailored to the needs of the individual animal and implemented by the owner results in weight loss accompanied by improvements in insulin sensitivity.

Transcatheter Embolisation of Proximal Type 1 Endoleaks Following Endovascular Aneurysm Sealing (EVAS) Using the Nellix Device: Technique and Outcomes.

AIM: To evaluate the technical success and mid-term outcomes following transcatheter embolisation of type 1a endoleak after Nellix endovascular aneurysm sealing (EVAS). MATERIALS AND METHODS: Seven patients (5 men; mean age 83; range 79-90) underwent transcatheter embolisation between July 2013 and August 2014. The average time from EVAS to embolisation was 136 days (range 6-301) and from endoleak diagnosis to embolisation was 20 days (range 2-50). Embolisation was performed with coils and Onyx in six cases and Onyx only in one case. Technical success, imaging and clinical outcomes of embolisation were reviewed. Technical success was defined as elimination of the endoleak on completion angiography and first imaging follow-up. Clinical success was defined as unchanged or decreased aneurysm sac size on subsequent follow-up (average 8 months; range 103-471 days). RESULTS: All cases were technically successful. One patient required a second endovascular procedure following Onyx reflux into the Nellix endograft and another patient required surgical closure of a brachial puncture site. All patients are endoleak free with stable sac size on the latest available follow-up imaging. CONCLUSION: If a type 1 endoleak occurs after EVAS, embolisation using Onyx with or without coils is feasible and effective with high technical success and freedom from endoleak recurrence at mid-term follow-up.

Thoracic Endovascular Aortic Repair for the Treatment of Aortic Dissection: Post-operative Imaging, Complications and Secondary Interventions.

Thoracic endovascular aortic repair (TEVAR) has become an accepted alternative to surgery for the treatment of aortic dissection (AD). Lifelong surveillance is obligatory following TEVAR to monitor the aortic morphology and detect associated complications. This is particularly important in AD where coverage of the primary intimal tear is necessary in achieving thrombosis and regression of the false lumen. A variety of imaging techniques may be used in assessing the technical success, outcome and complications, which may necessitate re-intervention. Of these, computed tomography angiography offers a fast, accessible and sensitive imaging modality and is established as the default surveillance tool. The purpose of this article is to review the imaging modalities, post-procedural appearances including complications and re-intervention strategies following TEVAR for AD.

Embolisation of a proximal type I endoleak post-Nellix aortic aneurysm repair complicated by reflux of Onyx into the Nellix endograft limb.

We report the first case of intervention for a proximal type 1 endoleak following Nellix endovascular aneurysm sealing repair of an aortic aneurysm. This was complicated by migration of Onyx into one of the Nellix graft limbs causing significant stenosis. Subsequent placement of a covered stent to affix the Onyx between the stent and the wall of the Nellix endograft successfully restored stent patency.

Prevalence and risk factors for hyperinsulinaemia in ponies in Queensland, Australia.

OBJECTIVES: To determine the prevalence of hyperinsulinaemia in a population of ponies in Queensland, Australia, and identify associated factors. METHODS: Breeders or traders of ponies within a 100 km radius of Gatton, Queensland, were recruited for study using an internet database. Clinical and management details were obtained, including body condition score, fat deposition and history or evidence of laminitis. Blood samples were analysed for serum insulin and triglyceride concentrations and plasma adrenocorticotrophic hormone (ACTH) and leptin concentrations following short-term removal from pasture and withholding of supplementary food for at least 12 h. RESULTS: Of 23 pony studs identified, 22 were available for visit. The study population consisted of 208 ponies: 70 Australian Ponies; 67 Welsh Mountain Ponies or Cobs; 51 Connemara Ponies; 20 Shetland ponies. We excluded 20 with suspected pituitary pars intermedia dysfunction (>15 years, ACTH >50 pg/mL). In total, 27% of the ponies (51/188) were hyperinsulinaemic (insulin >20 µIU/mL). The final multivariable model revealed increasing age, supplementary feeding and increased leptin and triglyceride concentrations to be associated with hyperinsulinaemia. CONCLUSIONS: Hyperinsulinaemia was prevalent and associated with age and evidence of metabolic disturbance, including elevated leptin and triglyceride concentrations, in this population. A significant number of ponies were at risk of hyperinsulinaemia, which has implications for strategies to reduce the risk of laminitis in this population.

Inhibition of TGF-ß signaling in genetically engineered tumor antigen-reactive T cells significantly enhances tumor treatment efficacy.

Transforming growth factor ß (TGF-ß) is a cytokine with complex biological functions that may involve tumor promotion or tumor suppression. It has been reported that multiple types of tumors secrete TGF-ß, which can inhibit tumor-specific cellular immunity and may represent a major obstacle to the success of tumor immunotherapy. In this study, we sought to enhance tumor immunotherapy using genetically modified antigen-specific T cells by interfering with TGF-ß signaling. We constructed three γ-retroviral vectors, one that expressed TGF-ß-dominant-negative receptor II (DNRII) or two that secreted soluble TGF-ß receptors: soluble TGF-ß receptor II (sRII) and the sRII fused with mouse IgG Fc domain (sRIIFc). We demonstrated that T cells genetically modified with these viral vectors were resistant to exogenous TGF-ß-induced smad-2 phosphorylation in vitro. The functionality of antigen-specific T cells engineered to resist TGF-ß signaling was further evaluated in vivo using the B16 melanoma tumor model. Antigen-specific CD8+ T cells (pmel-1) or CD4+ T cells (tyrosinase-related protein-1) expressing DNRII dramatically improved tumor treatment efficacy. There was no enhancement in the B16 tumor treatment using cells secreting soluble receptors. Our data support the potential application of the blockade of TGF-ß signaling in tumor-specific T cells for cancer immunotherapy.

Operator-controlled imaging significantly reduces radiation exposure during EVAR.

INTRODUCTION: Adoption of endovascular aneurysm repair (EVAR) has led to significant reductions in the short-term morbidity and mortality associated with abdominal aortic aneurysm (AAA) repair. However, EVAR may expose both patient and interventionalist to potentially harmful levels of radiation, particularly as more complex procedures are undertaken. The aim of this study was to assess whether changing from radiographer-controlled imaging to a system of operator-controlled imaging (OCI) would influence radiation exposure, screening time or contrast dose during EVAR. METHOD: Retrospective analysis identified patients that had undergone elective EVAR for infra-renal AAA before or after the change to operator-controlled imaging. Data were collected for radiation dose (measured as dose area product; DAP), screening time, total delivered contrast volume and operative duration. Data were also collected for maximum aneurysm diameter, patient age, gender and body mass index. RESULTS: 122 patients underwent EVAR for infra-renal AAA at a single centre between January 2011 and December 2011. 57 of these were prior to installation of OCI and 65 after installation. Median DAP was significantly lower after installation of OCI (4.9 mGy m(2); range 1.25-13.3) than it had been before installation (6.9 mGy m(2); range 1.91-95.0) (p = 0.005). Median screening times before and after installation of OCI were 20.0 min and 16.2 min respectively (p = 0.027) and median contrast volumes before and after the change to OCI were 100 ml and 90 ml respectively (p = 0.21). CONCLUSION: Introduction of operator-controlled imaging can significantly reduce radiation exposure during EVAR, with particular reduction in the number of 'higher-dose' cases.

Nephrogenic diabetes insipidus in a 14-year-old gelding.

CASE HISTORY: A 14-year-old Cleveland Bay cross gelding was presented with severe urinary incontinence that had been present for 1 year, and chronic polydipsia and polyuria over 4 years. Water intake had been recorded as 240 L over a 24-hour period. CLINICAL FINDINGS: The horse had marked urinary incontinence and polyuria and polydipsia. The urine was markedly hyposthenuric, but no abnormalities on urinalysis were detected. There were no other abnormal clinical or neurological signs. Haematological and serum biochemical examinations showed no abnormalities and ultrasonographic and endoscopic examination of the urinary tract did not reveal any abnormalities. The horse underwent a modified water deprivation test and failed to concentrate its urine after 5 days. 1-desamino-8-d-arginine vasopressin (DDAVP) was administered I/V but the urine remained isosthenuric with a specific gravity of 1.010. DIAGNOSIS: Nephrogenic diabetes insipidus. A definitive cause of the urinary incontinence was not found but overflow incontinence was considered a possibility. CLINICAL RELEVANCE: Despite being a rare condition in the horse diabetes insipidus should be considered in cases of severe polydipsia and polyuria in mature horses.

Efficient nonviral Sleeping Beauty transposon-based TCR gene transfer to peripheral blood lymphocytes confers antigen-specific antitumor reactivity.

Genetically engineered lymphocytes hold promise for the treatment of genetic disease, viral infections and cancer. However, current methods for genetic transduction of peripheral blood lymphocytes rely on viral vectors, which are hindered by production and safety-related problems. In this study, we demonstrated an efficient novel nonviral platform for gene transfer to lymphocytes. The Sleeping Beauty transposon-mediated approach allowed for long-term stable expression of transgenes at approximately 50% efficiency. Utilizing transposon constructs expressing tumor antigen-specific T-cell receptor genes targeting p53 and MART-1, we demonstrated sustained expression and functional reactivity of transposon-engineered lymphocytes on encountering target antigen presented on tumor cells. We found that transposon- and retroviral-modified lymphocytes had comparable transgene expression and phenotypic function. These results demonstrate the promise of nonviral ex vivo genetic modification of autologous lymphocytes for the treatment of cancer and immunologic disease.

Development of optimal bicistronic lentiviral vectors facilitates high-level TCR gene expression and robust tumor cell recognition.

In human gene therapy applications, lentiviral vectors may have advantages over gamma-retroviral vectors in several areas, including the ability to transduce nondividing cells, resistance to gene silencing and a potentially safer integration site profile. However, unlike gamma-retroviral vectors it has been problematic to drive the expression of multiple genes efficiently and coordinately with approaches such as internal ribosome entry sites or dual promoters. Using different 2A peptides, lentiviral vectors expressing two-gene T-cell receptors directed against the melanoma differentiation antigens gp100 and MART-1 were constructed. We demonstrated that addition of amino-acid spacer sequences (GSG or SGSG) before the 2A sequence is a prerequisite for efficient synthesis of biologically active T-cell receptors and that addition of a furin cleavage site followed by a V5 peptide tag yielded optimal T-cell receptor gene expression. Furthermore, we determined that the furin cleavage site was recognized in lymphocytes and accounted for removal of residual 2A peptides at the post-translational level with an efficiency of 20-30%, which could not be increased by addition of multiple furin cleavage sites. The novel bicistronic lentiviral vector developed herein afforded robust anti-melanoma activities to engineered peripheral blood lymphocytes, including cytokine secretion, cell proliferation and lytic activity. Such optimal vectors may have immediate applications in cancer gene therapy.

Is internal iliac artery embolization essential prior to endovascular repair of aortoiliac aneurysms?

Patients who undergo endovascular repair of aorto-iliac aneurysms (EVAR) require internal iliac artery (IIA) embolization (IIAE) to prevent type II endoleaks after extending the endografts into the external iliac artery. However, IIAE may not be possible in some patients due to technical factors or adverse anatomy. The aim of this study was to assess retrospectively whether patients with aorto-iliac aneurysms who fail IIAE have an increase in type II endoleak after EVAR compared with similar patients who undergo successful embolization. We retrospectively analyzed the records of 148 patients who underwent EVAR from December 1997 to June 2005. Sixty-one patients had aorto-iliac aneurysms which required IIAE before EVAR. Fifty patients had successful IIAE and 11 patients had unsuccessful IIAE prior to EVAR. The clinical and imaging follow-up was reviewed before and after EVAR. The endoleak rate of the embolized group was compared with that of the group in whom embolization failed. After a mean follow-up of 19.7 months in the study group and 25 months in the control group, there were no statistically significant differences in outcome measures between the two groups. Specifically, there were no type II endoleaks related to the IIA in patients where IIAE had failed. We conclude that failure to embolize the IIA prior to EVAR should not necessarily preclude patients from treatment. In patients where there is difficulty in achieving coil embolization, it is recommended that EVAR should proceed, as clinical sequelae are unlikely.

Actinomyces species as a cause of abscesses in nine horses.

The characteristics, history, clinical signs, treatment and outcome of nine horses with abscesses caused by Actinomyces species were reviewed. dna sequencing was used to determine the species of one of the isolates. The horses were one to 11 years of age, and the abscesses were most commonly located in the submandibular and retropharyngeal regions. The bacterium was usually cultured as the sole isolate and the horses were most often affected in the autumn. Most of the abscesses were treated with antimicrobials and drainage, but some of them recurred. The horses with submandibular abscesses had residual scar tissue that in some cases did not resolve.