Polymerisation of cyanoacrylates: The effect of sclero-embolic and contrast agents.

OBJECTIVES: The objective is to investigate the interaction of sclero-embolic and contrast agents with the polymerisation of medical grade n-butyl-cyanoacrylates. METHODS: An in vitro spectrophotometric absorbance method was developed to detect changes in light transmission to measure n-BCA polymerisation. The initiation and the rate-of-polymerisation of mixtures of n-BCA with sclero-embolic and contrast agents were investigated. RESULTS: Initiation of polymerisation: VENABLOCK™ and HISTOACRYL® were the fastest agents to polymerise, while VENASEAL™ was the slowest. Rate of polymerisation: Hypertonic saline inhibited the polymerisation of all n-BCAs, while hypertonic glucose prolonged the polymerisation rate. ETHANOL and detergent sclerosants had no effect. Contrast agents OMNIPAQUE™ and ULTRAVIST® initiated and prolonged the polymerisation of n-BCA, but in contrast, LIPIODOL® failed to initiate the process. CONCLUSIONS: The commercially available medical cyanoacrylates differ in their polymerisation rates. These polymerisation rates are further affected when these products are used in conjunction with other compounds, such as sclero-embolic and contrast agents.

Routine use of concurrent fluoroscopic imaging during superficial endovenous interventions: A position statement of the International Union of Phlebology, the Australasian College of Phlebology, the Australia and New Zealand Society for Vascular Surgery, the American Venous Forum, the American Vein and Lymphatic Society, the European College of Phlebology and the Interventional Radiology Society of Australasia.

International evidence-based guidelines recommend preoperative duplex ultrasound mapping in the assessment of chronic venous disease, and concurrent ultrasound imaging to guide superficial endovenous interventions such as endovenous laser ablation, radiofrequency ablation, cyanoacrylate adhesive closure, and sclerotherapy (ultrasound-guided sclerotherapy). Other imaging modalities such as venography, alone or in combination with computed tomography scan or magnetic resonance imaging, may be included in the preoperative assessment of a small and select group of patients to exclude central venous obstruction, certain deep venous pathologies, pelvic origin extrapelvic varices, and complex vascular malformations. The signatory scientific and medical societies recommend against the routine use of fluoroscopy and other radiation-based imaging in the investigation and treatment of superficial venous disease.

Routine use of concurrent fluoroscopic imaging during superficial endovenous interventions: A position statement of the International Union of Phlebology (UIP), the Australasian College of Phlebology (ACP), the Australia and New Zealand Society for Vascular Surgery (ANZSVS), the American Venous Forum (AVF), the American Vein and Lymphatic Society (AVLS), the European College of Phlebology (ECoP) and the Interventional Radiology Society of Australasia (IRSA).

International evidence-based guidelines recommend preoperative duplex ultrasound mapping in the assessment of chronic venous disease, and concurrent ultrasound imaging to guide superficial endovenous interventions such as endovenous laser ablation, radiofrequency ablation, cyanoacrylate adhesive closure, and sclerotherapy (ultrasound-guided sclerotherapy). Other imaging modalities such as venography, alone or in combination with computed tomography scan or magnetic resonance imaging, may be included in the preoperative assessment of a small and select group of patients to exclude central venous obstruction, certain deep venous pathologies, pelvic origin extrapelvic varices, and complex vascular malformations. The signatory scientific and medical societies recommend against the routine use of fluoroscopy and other radiation-based imaging in the investigation and treatment of superficial venous disease.

Selective internal radiation therapy for hepatocellular carcinoma: A 15-year multicenter Australian cohort study.

BACKGROUND AND AIM: The exact place for selective internal radiation therapy (SIRT) in the therapeutic algorithm for hepatocellular carcinoma (HCC) is debated. There are limited data on its indications, efficacy, and safety in Australia. METHODS: We performed a multicenter retrospective cohort study of patients undergoing SIRT for HCC in all Sydney hospitals between 2005 and 2019. The primary outcome was overall survival. Secondary outcomes were progression-free survival and adverse events. RESULTS: During the study period, 156 patients underwent SIRT across 10 institutions (mean age 67 years, 81% male). SIRT use progressively increased from 2005 (n = 2), peaking in 2017 (n = 42) before declining (2019: n = 21). Barcelona Clinic Liver Cancer stages at treatment were A (13%), B (33%), C (52%), and D (2%). Forty-four (28%) patients had tumor thrombus. After a median follow-up of 13.9 months, there were 117 deaths. Median overall survival was 15 months (95% confidence interval 11-19). Independent predictors of mortality on multivariable analysis were extent of liver involvement, Barcelona Clinic Liver Cancer stage, baseline ascites, alpha fetoprotein, and model for end-stage liver disease score. Median progression-free survival was 6.0 months (95% confidence interval 5.1-6.9 months). Following SIRT, 11% of patients were downstaged to curative therapy. SIRT-related complications occurred in 17%: radioembolization-induced liver disease (11%), pneumonitis (3%), gastrointestinal ulceration, and cholecystitis (1% each). Baseline ascites predicted for radioembolization-induced liver disease. CONCLUSION: We present the largest Australian SIRT cohort for HCC. We have identified several factors associated with a poor outcome following SIRT. Patients with early-stage disease had the best survival with some being downstaged to curative therapy.

LIPIODOL reduces the lytic activity of detergent sclerosants in vitro.

OBJECTIVES: Contrast agents are used widely in the interventional setting and in particularly in the management of vascular anomalies and have also been used in combination with sclero-embolic agents. There is limited information on the interaction of contrast agents with sclerosant agents when used as mixtures. The aim of this study was to determine the effect of mixing radiological contrast agents with detergent sclerosants and measuring the effect on change in lytic activity of detergent sclerosants in vitro and by proxy the change in potency. METHODS: Red blood cell lysis was assessed following the incubation of two commonly used contrast agents, LIPIODOL® and ULTRAVIST®, mixed with detergent sclerosants, FIBROVEIN®, sodium tetradecyl sulfate (STS), and AETHOXYSKLEROL®, polidocanol (POL). RESULTS: The density of both contrast agents was higher than STS and POL and neither of the detergent sclerosants were miscible in LIPIODOL. LIPIODOL on its own caused cell lysis (1.01%, p < 0.05) whereas ULTRAVIST did not. Fifty per cent cell lysis for sclerosant and LIPIODOL mix occurred at concentrations of: 0.041% (2.4 times greater than the control, p < 0.05) and 0.08% (3.6 times greater than the control, p = 0.06) for STS and POL, respectively. CONCLUSIONS: LIPIODOL, when mixed with sclerosant detergents (ratio 1:1) causes a reduction in the lytic activity of sclerosants and this effect was statistically significant and most prominent in lower sclerosant concentration mixtures.

Triage of patients with venous and lymphatic diseases during the COVID-19 pandemic - The Venous and Lymphatic Triage and Acuity Scale (VELTAS) : A consensus document of the International Union of Phlebology (UIP), Australasian College of Phlebology (ACP), American Vein and Lymphatic Society (AVLS), American Venous Forum (AVF), European College of Phlebology (ECoP), European Venous Forum (EVF), Interventional Radiology Society of Australasia (IRSA), Latin American Venous Forum, Pan-American Society of Phlebology and Lymphology and the Venous Association of India (VAI) This consensus document has been co-published in Phlebology [DOI: 10.1177/0268355520930884] and Journal of Vascular Surgery: Venous and Lymphatic Disorders [DOI: 10.1016/j.jvsv.2020.05.002]. The publications are identical except for minor stylistic and spelling differences in keeping with each journal's style. The contribution has been published under a Attribution-Non Commercial-No Derivatives 4.0 International (CC BY-NC-ND 4.0), (https://creativecommons.org/licenses/by-nc-nd/4.0/).

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semi-urgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/non-urgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.

Triage of patients with venous and lymphatic diseases during the COVID-19 pandemic - The Venous and Lymphatic Triage and Acuity Scale (VELTAS):: A consensus document of the International Union of Phlebology (UIP), Australasian College of Phlebology (ACP), American Vein and Lymphatic Society (AVLS), American Venous Forum (AVF), European College of Phlebology (ECoP), European Venous Forum (EVF), Interventional Radiology Society of Australasia (IRSA), Latin American Venous Forum, Pan-American Society of Phlebology and Lymphology and the Venous Association of India (VAI).

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semiurgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/nonurgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.

Status of the scalar singlet dark matter model.

One of the simplest viable models for dark matter is an additional neutral scalar, stabilised by a Z 2 symmetry. Using the GAMBIT package and combining results from four independent samplers, we present Bayesian and frequentist global fits of this model. We vary the singlet mass and coupling along with 13 nuisance parameters, including nuclear uncertainties relevant for direct detection, the local dark matter density, and selected quark masses and couplings. We include the dark matter relic density measured by Planck, direct searches with LUX, PandaX, SuperCDMS and XENON100, limits on invisible Higgs decays from the Large Hadron Collider, searches for high-energy neutrinos from dark matter annihilation in the Sun with IceCube, and searches for gamma rays from annihilation in dwarf galaxies with the Fermi-LAT. Viable solutions remain at couplings of order unity, for singlet masses between the Higgs mass and about 300 GeV, and at masses above ∼ 1 TeV. Only in the latter case can the scalar singlet constitute all of dark matter. Frequentist analysis shows that the low-mass resonance region, where the singlet is about half the mass of the Higgs, can also account for all of dark matter, and remains viable. However, Bayesian considerations show this region to be rather fine-tuned.

The role of excitotoxic injury in post-traumatic syringomyelia.

Fifty percent of patients with neurological deterioration from post-traumatic syringomyelia do not respond to treatment. Treatment failure is due in part to an incomplete understanding of the underlying aetiology. An animal model that mimics the human disease is required to investigate underlying pathophysiology and treatment options. A previous study was designed to mimic trauma-induced effects on the spinal cord that result in syringomyelia, combining an excitotoxic insult with kaolin-induced arachnoiditis. In this excitotoxic model, syringes were produced in 82% of animals. The aims of the current study were to improve the model to produce syringes in all animals treated, to examine the relative influences of excitotoxic injury and neuronal loss on syrinx formation, and to use magnetic resonance imaging (MRI) to examine syringes non-invasively. A temporal and dose profile of intraparenchymal quisqualic acid (QA) and subarachnoid kaolin was performed in Sprague Dawley rats. MRI was used to study four syrinx and six control animals. In one subgroup of animals surviving for 6 weeks, 100% (eight of eight) developed syringes. Syrinx formation and enlargement occurred in a dose and time dependent manner, whilst significant neuronal loss was only dose dependent. Animal syrinx histology closely resembled human post-traumatic syringomyelia. Axial T2-weighted MR images demonstrated syrinx presence. The results suggest that the formation of an initial cyst predisposes to syrinx formation in the presence of subarachnoid adhesions.