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.

899 serious adverse events including 13 deaths, 7 strokes, 211 thromboembolic events, and 482 immune reactions: The untold story of cyanoacrylate adhesive closure.

OBJECTIVE: The aim was to retrieve and analyse the serious adverse events of venous occlusion systems used in cyanoacrylate adhesive closure (CAC) submitted to regulatory agencies. METHODS: The Total Product Life Cycle (TPLC) database of the US Food and Drug Administration (FDA), the Database of Adverse Event Notifications (DAEN) of the Australian Therapeutic Goods Administration (TGA), and the Yellow Card database of the UK Medicines and Healthcare Products Regulatory Agency (MHRA) were reviewed. Three Freedom of Information (FOI) requests had to be submitted to the MHRA to obtain data. RESULTS: The TPLC contained 899 reports which included 13 cases of death, 7 strokes, 211 thromboembolic events, and 482 immune reactions. The DAEN recorded three reportable adverse events, and the MHRA recorded seven adverse incidents including one death. CONCLUSION: CAC is associated with serious adverse events including death. These events are under-reported in the medical literature and only sub-optimally reported to the regulatory agencies.

Pigmentation of lower limbs: Contribution of haemosiderin and melanin in chronic venous insufficiency and related disorders.

BACKGROUND: To determine the composition of skin pigmentation in chronic venous insufficiency (CVI) and other less common vascular conditions of lower limbs. METHODS: Forty-five skin biopsies were obtained from 17 patients. Samples were taken from pigmented regions and compared with control non-lesional samples from the same patient. Perl's Prussian Blue was used to identify haemosiderin and Schmorl's for melanin. RESULTS: Seven patients presented with CVI, one with concurrent livedo vasculopathy (LV). One patient had LV only. Two patients had acroangiodermatitis (AAD). Six patients had post-sclerotherapy pigmentation (PSP), one with concurrent post-inflammatory hyperpigmentation (PIH). One patient had PIH only. The predominant pigment in CVI samples was haemosiderin. C5-C6 patients showed increased epidermal melanin. LV, AAD, and PSP samples showed dermal haemosiderin but no increase in epidermal melanin. PIH samples showed prominent epidermal melanin whilst no haemosiderin was detected. CONCLUSION: The predominant pigment in CVI and other vascular conditions was haemosiderin. Melanin was present in later stages of CVI (C5-C6) and in PIH.

Sclerotherapy of lower limb veins: Indications, contraindications and treatment strategies to prevent complications - A consensus document of the International Union of Phlebology-2023.

BACKGROUND: Sclerotherapy is a non-invasive procedure commonly used to treat superficial venous disease, vascular malformations and other ectatic vascular lesions. While extremely rare, sclerotherapy may be complicated by serious adverse events. OBJECTIVES: To categorise contraindications to sclerotherapy based on the available scientific evidence. METHODS: An international, multi-disciplinary panel of phlebologists reviewed the available scientific evidence and developed consensus where evidence was lacking or limited. RESULTS: Absolute Contraindications to sclerotherapy where the risk of harm would outweigh any benefits include known hypersensitivity to sclerosing agents; acute venous thromboembolism (VTE); severe neurological or cardiac adverse events complicating a previous sclerotherapy treatment; severe acute systemic illness or infection; and critical limb ischaemia. Relative Contraindications to sclerotherapy where the potential benefits of the proposed treatment would outweigh the risk of harm or the risks may be mitigated by other measures include pregnancy, postpartum and breastfeeding; hypercoagulable states with risk of VTE; risk of neurological adverse events; risk of cardiac adverse events and poorly controlled chronic systemic illness. Conditions and circumstances where Warnings and Precautions should be considered before proceeding with sclerotherapy include risk of cutaneous necrosis or cosmetic complications such as pigmentation and telangiectatic matting; intake of medications such as the oral contraceptive and other exogenous oestrogens, disulfiram and minocycline; and psychosocial factors and psychiatric comorbidities that may increase the risk of adverse events or compromise optimal treatment outcomes. CONCLUSIONS: Sclerotherapy can achieve safe clinical outcomes provided that (1) patient-related risk factors and in particular all material risks are (1a) adequately identified and the risk benefit ratio is clearly and openly discussed with treatment candidates within a reasonable timeframe prior to the actual procedure; (1b) when an individual is not a suitable candidate for the proposed intervention, conservative treatment options including the option of 'no intervention as a treatment option' are discussed; (1c) complex cases are referred for treatment in controlled and standardised settings and by practitioners with more expertise in the field; (1d) only suitable individuals with no absolute contraindications or those with relative contraindications where the benefits outweigh the risks are offered intervention; (1e) if proceeding with intervention, appropriate prophylactic measures and other risk-mitigating strategies are adopted and appropriate follow-up is organised; and (2) procedure-related risk factors are minimised by ensuring the treating physicians (2a) have adequate training in general phlebology with additional training in duplex ultrasound, procedural phlebology and in particular sclerotherapy; (2b) maintain their knowledge and competency over time and (2c) review and optimise their treatment strategies and techniques on a regular basis to keep up with the ongoing progress in medical technology and contemporary scientific evidence.

Myopericytomatosis: A rare entity mimicking other vascular tumours and malformations.

Myopericytoma is a rare tumour which typically presents as a benign lesion that mimics features of other more common vascular tumours and malformations. We present a case of a symptomatic diffuse myopericytomatosis of the left abdomen presenting as multiple subcutaneous vascular tumours detected on ultrasound and treated with ultrasound-guided sclerotherapy.

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.

Skin necrosis following sclerotherapy. Part 2: Risk minimisation and management strategies.

Tissue necrosis is a serious but rare complication of sclerotherapy. Early detection and targeted management are essential to prevent progression and minimise serious complications. In the first instalment of this paper, we reviewed the pathogenic mechanisms of post-sclerotherapy necrosis. Here, we describe risk minimisation and management strategies.Risk factors must be addressed to reduce the chance of necrosis following sclerotherapy. These may be treatment-related including poor choice of sclerosant type, concentration, volume or format, poor injection technique, suboptimal ultrasound visualisation and treatment of vessels in high-risk anatomical areas. Risk factors specific to individual patients should be identified and optimised pre-operatively.Tissue necrosis is more likely to occur with extravasation of irritant sclerosants such as absolute alcohol, sodium iodide, bleomycin and hypertonic saline, whereas extravasation of foam detergent sclerosants rarely results in tissue loss. Proposed treatments for extravasation of irritant sclerosants include infiltration of an isotonic fluid and hyaluronidase. Management of inadvertent intra-arterial injections may require admission for neurovascular observation and monitoring for ischaemia, intravenous systemic steroids, anticoagulation, thrombolysis and prostanoids infusion when required. Treatment of veno-arteriolar reflex vasospasm (VAR-VAS) necrosis follows the same protocol involving systemic steroids but rarely requires hospital admission and may not require anticoagulation.In general, treatment of post-sclerotherapy necrosis is challenging and most proposed treatment measures are not evidence-based and only supported by anecdotal personal experience of clinicians. Despite all measures, once the necrosis has set in, it is very difficult to reverse the process and all measures described here may only be useful in prevention of progression and extension of the ulceration.Mid to long-term measures include addressing exacerbating factors, management of medical and psychosocial comorbidities, treatment of secondary infections and referrals to relevant specialists. All ulcers should be managed with compression and prescribed dressing regimes in line with the healing stage of the ulcer.