Novel developments in foam sclerotherapy: Focus on Varithena® (polidocanol endovenous microfoam) in the management of varicose veins

Endoscopic polidocanol foam sclerobanding for the treatment of grade II-III internal hemorrhoids: A prospective, multi-center, randomized study

BACKGROUND

Endoscopic rubber band ligation (ERBL) is a nonsurgical technique for the treatment of symptomatic internal hemorrhoids but is limited by recurrence and post-procedural pain.

AIM

To evaluate satisfaction, long-term recurrence, and post-procedural pain in managing internal hemorrhoids using a combination of polidocanol foam sclerotherapy and ERBL.

METHODS

This was a prospective, multicenter, randomized study. A total of 195 consecutive patients diagnosed with grade II-III internal hemorrhoids were enrolled from four tertiary hospitals and randomly divided into a cap-assisted endoscopic polidocanol foam sclerobanding (EFSB) or an ERBL group. All patients were followed-up for 12 months. Symptom-based severity and post-procedural pain were assessed using a hemorrhoid severity score (HSS) and a visual analog scale (VAS). Continuous variables were reported as medians and interquartile range.

RESULTS

One hundred and ninety-five patients were enrolled, with 98 in the EFSB group. HSS was lower in the EFSB group than in the ERBL group at 8 weeks [4.0 (3.0-5.0) vs 5.0 (4.0-6.0), P = 0.003] and 12-month [2.0 (1.0-3.0) vs 3.0 (2.0-3.0), P < 0.001] of follow-up. The prolapse recurrence rate was lower in the EFSB group at 12 months (11.2% vs 21.6%, P = 0.038). Multiple linear regression analysis demonstrated that EFSB treatment [B = -0.915, 95% confidence interval (CI): -1.301 to -0.530, P = 0.001] and rubber band number (B = 0.843, 95%CI: 0.595-1.092, P < 0.001) were negatively and independently associated with the VAS score 24 hours post-procedure. The median VAS was lower in the EFSB group than in the ERBL [2.0 (1.0-3.0) vs 3.0 (2.0-4.0), P < 0.001].

CONCLUSION

Cap-assisted EFSB provided long-term satisfaction and effective relief from the recurrence of prolapse and pain 24 hours post-procedure.

Liquid foam improves potency and safety of gene therapy vectors

Interest in gene therapy medicines is intensifying as the first wave of gene-correcting drugs is now reaching patient populations. However, efficacy and safety concerns, laborious manufacturing protocols, and the high cost of the therapeutics are still significant barriers in gene therapy. Here we describe liquid foam as a vehicle for gene delivery. We demonstrate that embedding gene therapy vectors (nonviral or viral) in a methylcellulose/xanthan gum-based foam formulation substantially boosts gene transfection efficiencies in situ, compared to liquid-based gene delivery. We further establish that our gene therapy foam is nontoxic and retained at the intended target tissue, thus minimizing both systemic exposure and targeting of irrelevant cell types. The foam can be applied locally or injected to fill body cavities so the vector is uniformly dispersed over a large surface area. Our technology may provide a safe, facile and broadly applicable option in a variety of clinical settings.

Three-year follow-up analysis of automated microfoam preparation system for great saphenous vein incompetence and varicose veins sclerotherapy treatment

BACKGROUND

To describe the treatment of patients with great saphenous vein (GSV) incompetence and varicose veins (VVs), utilizing an Automated Microfoam Preparation System (AMPS, Varixio®, VB Devices, Barcelona, Spain).

METHODS

Adults between January and June 2021 were included. The AMPS system was used for foam preparation. Sclerotherapy treatment followed international recommendations. The primary endpoint was GSV closure rate after 36 months.

RESULTS

164 patients were enrolled. During the 7-day follow-up period, all GSVs showed complete closure, which was maintained at the 1-year mark. No major complications were reported. A cumulative complete GSV recanalization rate of 6.1% and a partial recanalization rate of 26.8% after 36 months were noted. Some patients (9.7%) required additional treatment. A higher BMI was associated with complete recanalization.

CONCLUSION

The AMPS offers an easy-to-use and standardized procedure, potentially enhancing treatment outcomes if compared with manual preparation. Caution is advised when treating obese patients.

Comparative effectiveness of non-compounded polidocanol 1% endovenous microfoam (Varithena) ablation versus endovenous thermal ablation utilizing a systematic review and network meta-analysis

OBJECTIVE

We compared the effectiveness and safety of polidocanol 1% endovenous microfoam ablation vs endovenous thermal ablation with radiofrequency or laser energy for treatment of venous insufficiency caused by lower extremity truncal vein incompetence via network meta-analysis of published comparative evidence.

METHODS

We conducted a systematic literature review following best practices, including a prospective protocol. We screened studies published in English from 2000 to 2023 for randomized and nonrandomized studies reporting direct or indirect comparisons between polidocanol 1% endovenous microfoam and endovenous thermal ablation. Thirteen studies met our eligibility criteria for the network meta-analysis. The co-primary effectiveness outcomes were the closure rate ≥3 months after procedure and the average change in the Venous Clinical Severity Score. For the subgroup of venous ulcer patients, the ulcer healing rate was the primary effectiveness outcome. The secondary outcomes included safety and patient-reported outcomes. Network meta-analyses were conducted on outcomes having sufficient data. Categorical outcomes were summarized using odds ratios (ORs) with 95% confidence intervals (CIs). Sensitivity tests and estimates of network inconsistency were used to investigate the robustness of our meta-analysis.

RESULTS

We found that polidocanol 1% endovenous microfoam was not significantly different statistically from endovenous thermal ablation for venous closure (OR, 0.65; 95% CI, 0.36-1.18; P = .16). Although not the primary aim of the study, the network meta-analysis also provided evidence to confirm our supposition that polidocanol 1% endovenous microfoam was significantly differentiated statistically from physician-compounded foam, with higher odds for vein closure (OR, 2.91; 95% CI, 1.58-5.37; P < .01). A sensitivity analysis using the longest available time point for closure in each study, with a minimum of 12 months of follow-up (median, 48 months; range, 12-72 months), showed results similar to those of the main analysis. No association was found between the risk of deep vein thrombosis and the treatment received. The available data were insufficient for a network meta-analysis of Venous Clinical Severity Score improvement and ulcer healing rates.

CONCLUSIONS

Polidocanol 1% endovenous microfoam was not significantly different statistically from endovenous thermal ablation for venous closure and deep vein thrombosis risk for chronic venous insufficiency treatment, based on a network meta-analysis of published evidence. Polidocanol 1% endovenous microfoam was significantly differentiated statistically from physician-compounded foam, with higher odds of vein closure. A sensitivity analysis found venous closure findings were robust at follow-up intervals of 12 months or greater and for up to 6 years. New evidence meeting the inclusion criteria for this review will be incorporated at regular intervals into a living network meta-analysis.

Comparison of day surgery between varicose veins with and without superficial venous thrombosis below knee: a propensity score-matched analysis

OBJECTIVES

Development of endovenous treatment and sclerotherapy technology makes it feasible for clinicians to treat varicose veins (VV) through day surgery (DS). Superficial venous thrombosis (SVT) of lower extremities is a common complication of VV. This study aimed to investigate whether the existence of SVT below knee affect the safety and efficacy of DS for VV patients.

METHODS

This is a single-center retrospective study. Clinical data of 593 VV patients was retrospectively analyzed. Raw data were matched by the using of propensity score matching model. Operation time, technical failure, postoperative DVT, skin burns, saphenous nerve injury, subcutaneous induration, and bleeding were compared between the groups. Also, we compared VV recurrence, SVT formation, DVT events and the change of VCSS score with 12 months.

RESULTS

Fifty-nine patients complicated with SVT below knee were matched with 118 patients had VV only. Perioperative and follow-up outcomes were similar in both groups except for the number of incisions (median = 6 [5, 7] VS median = 4 [4, 5], P < 0.001). Both groups experienced a great decrease in VCSS score.

CONCLUSION

We systematically compared the clinical outcomes of DS in VV patients. Our results indicate DS is safe and effective for patients with VV, whether accompanied by SVT below the knee.

TRIAL REGISTRATION

The ClinicalTrials.gov identifier for this trial is NCT05380895 (retrospectively registered).

Endovenous Laser Ablation-Phlebectomy-Sclerotherapy Hybrid Treatment for Venous Insufficiency: A Case Report

A hybrid treatment approach was used to successfully manage bilateral varicose veins in a 50-year-old female patient. The patient had venous insufficiency and presented with pain, swelling, and discoloration in her legs. The treatment plan consisted of two sessions of endovenous laser ablation (EVLA) to treat venous reflux, followed by two phlebectomies for residual bulging varicose veins. After a three-month follow-up, an ultrasound evaluation showed no venous reflux, indicating successful treatment. However, small reticular and spider veins remained, so the patient underwent four sessions of foam sclerotherapy using polidocanol as the sclerosant. On her three-month follow-up post-sclerotherapy, the patient reported significant improvement in symptoms, and ultrasound evaluation showed no venous reflux in major veins. The hybrid approach combining EVLA, sclerotherapy, and phlebectomy provided effective treatment for the patient, resulting in symptom improvement and positive cosmetic outcomes.

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.

Endovascular Venous Interventions - A State-of-the-Art Review

Venous vascular diseases are an important clinical entity estimated to affect several million people worldwide. Deep vein thrombosis (DVT) is a common venous disease with a population variable prevalence of 122 to 160 persons per 100,000 per year, whereas pulmonary embolism (PE) affects up to 60 to 70 per 100 000 and carries much higher mortality. Chronic venous diseases, which cause symptoms like leg swelling, heaviness, pain, and discomfort, are most prevalent in the elderly and significantly impact their quality of life. Some estimate that chronic vascular diseases account for up to 2% of healthcare budgets in Western countries. Treating venous vascular disease includes using systemic anticoagulation and interventional therapies in some patient subsets. In this comprehensive review, we discuss endovascular treatment modalities in the management of venous vascular diseases.

Evaluation of the Effects of Polidocanol Injection in the Treatment of Temporomandibular Joint Hypermobility - A Prospective Study

Introduction

Sclerosing agents have been used for temporomandibular joint (TMJ) hypermobility since decades, some of which are ethanolamine oleate, and OK-432, sodium psylliate (sylnasol), but there are no studies on the usage of polidocanol - a well-known sclerosing agent which does not have much side effects and is inexpensive. Hence, this study evaluates the effect of polidocanol injection in the treatment of TMJ hypermobility.

Methodology

This was a prospective observational study in which patients with chronic TMJ hypermobility were included. Out of the 44 patients who had symptoms of clicking and pain of the TMJ, 28 were diagnosed as internal derangement of the TMJ. The final analysis included 15 patients in whom multiple injections of polidocanol were given on the basis of post-operative parameters. The sample size was calculated based on a significance level of 0.05 and a power of 80%.

Results

Overall, a success rate of 86.6% (13/15) was encountered at the end of three months, with seven patients not reporting any further episodes of dislocation after one injection and six patients not reporting any episode of dislocation after two injections.

Discussion

Polidocanol sclerotherapy can be used as a treatment modality for chronic recurrent dislocation of the TMJ, rather than opting for more invasive procedures for the same.

Skin necrosis following sclerotherapy. Part 1: Differential diagnosis based on classification of pathogenic mechanisms

Background: Tissue necrosis is a significant but uncommon complication of sclerotherapy. The pathogenic mechanisms of this often-debilitating complication have been poorly described in the literature.Purpose: To elucidate the pathological mechanisms, we propose a morphological approach to classify sclerotherapy-induced skin necrosis into two categories of round and stellate (star-like) necrosis.Research Design: Comprehensive literature review was conducted.Results: Round necrosis is typically caused by extravasation of sclerosants. It typically presents as an ulcer with smooth and non-geographic borders. Historically, extravasation has been cited as the main cause of sclerotherapy-related necrosis. While this may be the case with osmotic or irritant sclerosants, it is far less likely with the use of detergent agents particularly in the foam format.The more commonly encountered pattern of stellate necrosis is an ischaemic ulcer secondary to arterial/arteriolar occlusion. In contrast to round necrosis, stellate necrosis follows an intra-vascular injection of sclerosants such as an inadvertent intra-arterial injection. But more frequently, stellate necrosis may follow a perfectly executed intra-venous or intra-telangiectatic delivery of sclerosants. Several pathogenic pathways can be considered. The physiologic response of veno-arteriolar reflex vasospasm (VAR-VAS) is possibly the most frequent pathway. It follows a high-pressure injection of the sclerosant in a target vein resulting in a rapid rise of intravenous pressures which in-turn would trigger a sympathetic neuronal reflex vasospasm of the pre-capillary sphincters and a corresponding opening of the normally closed arterio-venous anastomoses (AVAs). This communication would allow entry of the sclerosing agent into the arteriolar side of the circulation resulting in arteriolar occlusion and infarction of the corresponding skin. Similarly, an intravenous administration of sclerosants in the vicinity of defective boundary valves or persistently open AVAs can result in the entry of detergent agents into the arteriolar side of the microvasculature causing an ischemic stellate ulcer.Conclusions: In this first instalment of these two-part series, we review the pathogenic mechanisms of post-sclerotherapy necrosis. In the second instalment, we describe risk minimisation and management strategies.

Treatment of facial hypertrophic capillary malformations with tumescent-assisted sclerotherapy

Facial capillary malformations (CMs) become hypertrophic and nodular overtime and pose great therapeutic challenge. Here, we describe safe and effective use of tumescent-assisted sclerotherapy (TAS) in conjunction with yellow vascular laser (577 nm) for the treatment of HFCMs. Three patients underwent TAS were included in the case series, and complete resolution in nodularity was achieved in all patients with TAS, with no major complications such as skin necrosis, distal embolisation, blindness and neurological adverse events such as stroke or TIA occurred in any patients.

Efficacy of Lauromacrogol Injection for Ablation of Benign Predominantly Cystic Thyroid Nodules and Related Factors: A Prospective Study

OBJECTIVE

To prospectively evaluate the efficacy of lauromacrogol injection for ablation (LIA) of benign predominantly cystic thyroid nodules and its related factors.

MATERIALS AND METHODS

A total of 142 benign predominantly cystic thyroid nodules (median volume, 12.5 mL; range, 0.4-156 mL) in 137 patients (male:female sex ratio, 36:101; mean age ± standard deviation [SD], 49 ± 13 years) were treated with LIA after being confirmed as benign via cytology. The volume reduction rate (VRR) of the nodules and cosmetic score were evaluated during follow-up at 1, 3, and 6 months after treatment and every 6 months thereafter. A VRR of ≥ 50% at the 12-month follow-up was considered to indicate effective treatment. The associations between the clinical factors and nodular ultrasound features, including the initial nodule volume, proportion of solid components, vascularity grade and ineffective treatment (VRR of < 50% at the 12-month follow-up), and regrowth were analyzed.

RESULTS

All patients completed follow-up for at least 12 months. The average ± SD follow-up period was 32 ± 11 months (range, 12-54 months). The effective treatment rate was 73.2% (104/142), while the regrowth rate was 12.0% (17/142) at the last follow-up. Grade 2-3 intranodular vascularity in the solid components of the nodules was the only independent factor associated with ineffective treatment, with an odds ratio (reference category, grade 0-1) of 3.054 (95% confidence interval, 1.148-8.127) (p = 0.025).

CONCLUSION

LIA is an effective treatment for predominantly cystic thyroid nodules. Grade 2-3 intranodular vascularity in the solid components of nodules is the only independent risk factor for ineffective LIA.

Association of great saphenous vein diameter and clinical severity score after treatment of severe chronic venous insufficiency with foam sclerotherapy

Objectives: to evaluate the association of the greater saphenous vein (GSV) diameter in the treatment of patients with severe chronic venous insufficiency (C6 CEAP classification) with ultrasound-guided polidocanol foam sclerotherapy (UGFS).  Methods: A prospective, descriptive and analytical study of 28 patients (30 limbs) that underwent UGFS. Patients were divided into 2 subgroups by GSV diameter (< 8 mm and ≥ 8 mm). Variables analyzed were ulcer healing, clinical intercurrences, clinical CEAP classification, Venous Clinical Severity Score (VCSS), diameter of the treated vein and presence of occlusion or recanalization by Doppler ultrasound. Patients were analyzed at the 1st, 3rd, and 6th months post-treatment. Results: The average age was 68.7 ± 10.5 years, 23 (82,1%) were women, and the average body mass index was 29.2 kg/m2. Although an improvement in VCSS score was observed during follow-up, no significant intergroup difference was noted. Seventeen (56%) limbs presented occlusion of the treated vein at the 1st month, 11 (36%) at the 3rd month, and 9 (30%) at the 6th month of follow-up. The ulcer healing rate was 56,6%. The average ulcer healing time was 90 days. Three (10%) patients presented with ulcer recurrence at the 6th month.  Survival analysis showed no significant difference in ulcer healing rate between subgroups after one year of follow-up (log-rank, p = 0,178). Conclusion: There was no difference between the subgroups of large and small VSM diameter in terms of symptom severity. However, significant reduction of VCSS and pain relief was observed after foam sclerotherapy.

Spectral Properties of Foams and Emulsions

The optical and spectral properties of foams and emulsions provide information about their micro-/nanostructures, chemical and time stability and molecular data of their components. Foams and emulsions are collections of different kinds of bubbles or drops with particular properties. A summary of various surfactant and emulsifier types is performed here, as well as an overview of methods for producing foams and emulsions. Absorption, reflectance, and vibrational spectroscopy (Fourier Transform Infrared spectroscopy-FTIR, Raman spectroscopy) studies are detailed in connection with the spectral characterization techniques of colloidal systems. Diffusing Wave Spectroscopy (DWS) data for foams and emulsions are likewise introduced. The utility of spectroscopic approaches has grown as processing power and analysis capabilities have improved. In addition, lasers offer advantages due to the specific properties of the emitted beams which allow focusing on very small volumes and enable accurate, fast, and high spatial resolution sample characterization. Emulsions and foams provide exceptional sensitive bases for measuring low concentrations of molecules down to the level of traces using spectroscopy techniques, thus opening new horizons in microfluidics.

Adverse neurological events after sodium tetradecyl sulfate foam sclerotherapy - A prospective, observational study of 8056 treatments

BACKGROUND

Ultrasound guided foam sclerotherapy (UGFS) is a flexible and highly utilised tool in the treatment of varicose veins (VVs), both as a primary treatment and as an adjunct to other treatments. Concern remains regarding the risk of neurological adverse events (AEs) such as migraine, visual disturbance and serious adverse events (SAEs) such as cerebrovascular accident that have been reported after UGFS treatments.

AIM

To determine the incidence of neurological AEs and SAEs after UGFS.

METHODS

A prospective, multicentre, post-authorisation safety study across Europe (both private and government) was performed between January 2015-2020. Neurological adverse events after UGFS with Fibrovein® (Sodium Tetradecyl Sulfate) 1 and 3% physician generated foam.

RESULTS

8056 patients underwent treatment. There were 46 AE (including 5 SAEs), 30 (65%) SAEs were in female patients. Mean age was 55 years with mean body mass index (BMI) of 27. Univariable logistic regression demonstrate that UGFS only treatment (i.e. no adjunctive treatment), liquid-to-gas ratio, gas type and total foam volume (1% sodium tetradecyl sulfate, STS) were significantly associated with the odds of experiencing the outcome. Multivariable logistic regression model exhibits that migraine and total foam volume (1% STS) maintained statistical significance thus associated with the odds of adverse events.

CONCLUSIONS

This study demonstrates that UGFS with Fibrovein is safe with a very low incidence of neurological AEs and SAEs. Past history of migraine, use of physiological gas (O₂/CO₂) and increasing volumes of 1% foam increase the risk of AEs.

Thrombotic complications of superficial endovenous ablation: a contemporary review of thermal and non-thermal techniques

Endovenous ablation has become the preferred means to treat superficial venous insufficiency. Ablative technologies have evolved to include a variety of both thermal and nonthermal techniques. The reported thrombotic complications of endovenous heat induced thrombosis (EHIT) and deep venous thrombosis (DVT) associated with thermal techniques are low (<2% overall). However, the limited data on newer non-thermal technologies suggest these modalities may have thrombotic complication rates upwards of 6%. Additionally, the pathophysiology of thrombotic events related to mechanochemical ablative techniques may differ from EHIT, and thus, may have different implications for management. Described is a case report of a stroke after cyanoacrylate ablation of the great saphenous vein, and a review of the current literature reporting the thrombotic complications associated with current thermal and non-thermal techniques. There exists a need for high volume studies on newer ablative techniques to fully understand their associated thrombotic complications. This review highlights the need for a comprehensive classification system and standard treatment algorithm encompassing of thrombotic complications associated with both thermal and non-thermal ablative techniques.

Efficacy and safety of polidocanol in the treatment of varicose veins of lower extremities: A protocol for systematic review and meta-analysis

BACKGROUND

The varicose veins of the lower extremities showed earthworm-like dilatation and venous protrusion of the lower extremities. Polidocanol foam sclerotherapy, as a minimally invasive treatment with rapid recovery, less trauma and not easy to relapse, has achieved good results in clinical, but it is lack of evidence-based medicine. The purpose of this study is to evaluate the efficacy and safety of polidocanol in the treatment of varicose veins of the lower extremities by meta-analysis.

METHOD

Chinese National Knowledge Infrastructure, Wanfang Database, Chinese Scientifific Journals Database, China Biology Medicine disc, PubMed, EMBASE database, Web of Science, and Cochrane Library will be used as search sources to conduct for randomized controlled trials of polidocanol in the treatment of varicose veins of lower extremities. The search time is set from the establishment of the database in December 2020 in this study. Two researchers independently extract, delete files, extract data and evaluate the quality. Revman software version 5.3 will be used for statistical analysis of data.

RESULT

In this study, the efficacy and safety of polidocanol in the treatment of varicose veins of the lower extremities will be evaluated in terms of total effective rate, incidence of complications and recurrence rate.

CONCLUSION

This study will provide reliable evidence-based evidence for the clinical application of polidocanol in the treatment of varicose veins of lower extremities.

ETHICS AND DISSEMINATION

Private information from individuals will not be published. This systematic review also does not involve endangering participant rights. Ethical approval will not be required. The results may be published in a peer-reviewed journal or disseminated at relevant conferences.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/AUR4X.

Characterisation and optimisation of foams for varicose vein sclerotherapy

BACKGROUND

Foam sclerotherapy is the process of using an aqueous foam to deliver surfactant to a varicose vein to damage vein wall endothelial cells, causing the vein to spasm, collapse and ultimately be re-absorbed into the body. Aqueous foams are complex fluids that can exhibit a significant yield stress and high effective viscosity which depend on their composition, particularly the bubble size and liquid fraction.

OBJECTIVE

To characterise the properties of foams used for varicose vein sclerotherapy and determine their effectiveness in the displacement of blood during sclerotherapy.

METHODS

Foams are modelled as yield stress fluids and their flow profiles in a model vein are predicted. Values of the yield stress are determined from experimental data for three different foams using the Sauter mean of the bubble size distribution. Along with the measured liquid fraction of the foams, this information is collected into a Bingham number which entirely characterises the process of sclerotherapy.

RESULTS

Polydispersity in bubble size has a strong effect on the yield stress of a foam and the Sauter mean of the size distribution better captures the effects of a few large bubbles. Reducing the polydispersity increases the yield stress, and a higher yield stress results in a larger plug region moving along the vein, which is more effective in displacing blood. The width of the plug region is proportional to the Bingham number, which also has a quadratic dependence on the liquid fraction of the foam. Assuming typical values for the rate of injection of a foam, we predict that for a vein of diameter 5 mm, the most effective foams have low liquid fraction, a narrow size distribution, and a Bingham number B ≈ 4.5.

CONCLUSIONS

The Sauter mean radius provides the most appropriate measure of the bubble size for sclerotherapy and the Bingham number then provides a simple measure of the efficacy of foam sclerotherapy in a vein of a given size, and explains the ability of different foams to remove varicose veins. Foams containing small bubbles, with a narrow size distribution, and a low liquid fraction are beneficial for sclerotherapy.

Medicine and Phlebolymphology: Time to Change?

Biomedical science is undergoing a reappraisal of its scientific advancement process and of the related healthcare management. Progress in medicine should combine improvements of knowledge, efficacy, and safety of diagnostic/therapeutic procedures, with adequate cost-effectiveness profiles. This narrative review is aimed at assessing in medicine, more specifically in phlebology and lymphology: (a) scientific literature possible biases, (b) the level of evidence, comprehensiveness, and cost-effectiveness of the main therapeutic options, and (c) the possible contribution of integrative and translational medicine. Current medical research may have cognitive biases, or industry-tied influences, which impacts clinical practice. Some reductionism, with an increasing use of drugs and technology, often neglecting the understanding and care of the root causative pathways of the diseases, is affecting biomedical science as well. Aging brings a relevant burden of chronic degenerative diseases and disabilities, with relevant socio-economic repercussions; thus, a major attention to cost-effectiveness and appropriateness of healthcare is warranted. In this scenario, costly and innovative but relatively validated therapies may tend to be adopted in venous and lymphatic diseases, such as varicose veins, leg venous ulcer, post-thrombotic syndrome, pelvic congestion syndrome, and lymphedema. Conversely, a more comprehensive approach to the basic pathophysiology of chronic venous and lymphatic insufficiency and the inclusion of pharmacoeconomics analyses would benefit overall patients’ management. Erroneous lifestyle and nutrition, together with chronic stress-induced syndromes, significantly influence chronic degenerative phlebo-lymphatic diseases. The main active epigenetic socio-biologic factors are obesity, dysfunctions of musculo-respiratory-vascular pumps, pro-inflammatory nutrition, hyperactivation of stress axis, and sedentarism. An overall critical view of the scientific evidence and innovations in phebolymphology could be of help to improve efficacy, safety, and sustainability of current practice. Translational and integrative medicine may contribute to a patient-centered approach. Conversely, reductionism, eminence/reimbursement-based decisional processes, patients’ lack of education, industry-influenced science, and physician’s improvable awareness, may compromise efficacy, safety, appropriateness, and cost-effectiveness of future diagnostic and therapeutic patterns of phlebology and lymphology.

Effect of Hyaluronic Acid and Pluronic-F68 on the Surface Properties of Foam as a Delivery System for Polidocanol in Sclerotherapy

The use of foams to deliver bioactive agents and drugs is increasing in pharmaceutics. One example is the use of foam as a delivery system for polidocanol (POL) in sclerotherapy, with the addition of bioactive compounds to improve the delivery system being a current subject of study. This work shows the influence of two bioactive additives on the structure and stability of POL foam: hyaluronic acid (HA) and Pluronic-F68 (F68). HA is a natural non-surface-active biopolymer present in the extracellular matrix while F68 is a surface-active poloxamer that is biocompatible with plasma-derived fluids. Both additives increase the bulk viscosity of the sample, improving foam stability. However, HA doubled and F68 quadruplicated the foam half lifetime of POL. HA reduced the size and polydispersity of the bubble size distribution and increased the surface elasticity with respect to POL. Both facts have a positive impact in terms of foam stability. F68 also altered bubble structure and increased surface elasticity, again contributing to the enhancement of foam stability. The surface characterization of these systems is important, as in foam sclerotherapy it is crucial to assure the presence of POL at the surface of the bubbles in order to deliver the sclerosant agent in the target vein.

Evaluating patient preferences for thermal ablation versus nonthermal, nontumescent varicose vein treatments

OBJECTIVE

To measure patient preferences for attributes associated with thermal ablation and nonthermal, nontumescent varicose vein treatments.

METHODS

Data were collected from an electronic patient preference survey taken by 70 adult participants (aged 20 years or older) at three Center for Vein Restoration clinics in New Jersey from July 19, 2019, through August 13, 2019. Survey participation was voluntary and anonymous (participation rate of 80.5% [70/87]). Patients were shown 10 consecutive screens that displayed three hypothetical treatment scenarios with different combinations of six attributes of interest and a none option. Choice-based conjoint analysis estimated the relative importance of different aspects of care, trade-offs between these aspects, and total satisfaction that respondents derived from different healthcare procedures. Market simulation analysis compared clusters of attributes mimicking thermal ablation and nonthermal, nontumescent treatments.

RESULTS

Of the six attributes studied, out-of-pocket (OOP) expenditures were the most important to patients (37.2%), followed by postoperative discomfort (17.1%), risk of adverse events (16.3%), time to return to normal activity (11.0%), number of injections (10.0%), and number of visits (8.4%). Patients were willing to pay the most to avoid postoperative discomfort ($68.9) and risk of adverse events ($65.8). The market simulation analysis found that, regardless of the level of OOP spending, 60% to 80% of respondents favored attribute combinations corresponding with nonthermal, nontumescent procedures over thermal ablation, and that less than 1% of participants would forgo either treatment under no cost sharing.

CONCLUSIONS

Patients are highly sensitive to OOP costs for minimally invasive varicose vein treatments. Market simulation analysis favored nonthermal, nontumescent procedures over thermal ablation.

Foam-in-vein: A review of rheological properties and characterization methods for optimization of sclerosing foams

Varicose veins are chronic venous defects that affect >20% of the population in developed countries. Among potential treatments, sclerotherapy is one of the most commonly used. It involves endovenous injection of a surfactant solution (or foam) in varicose veins, inducing damage to the endothelial layer and subsequent vessel sclerosis. Treatments have proven to be effective in the short-term, however recurrence is reported at rates of up to 64% 5-year post-treatment. Thus, once diagnosed with varicosities there is a high probability of a permanently reduced quality of life. Recently, foam sclerotherapy has become increasingly popular over its liquid counterpart, since foams can treat larger and longer varicosities more effectively, they can be imaged using ultrasound, and require lower amounts of sclerosing agent. In order to minimize recurrence rates however, an investigation of current treatment methods should lead to more effective and long-lasting effects. The literature is populated with studies aimed at characterizing the fundamental physics of aqueous foams; nevertheless, there is a significant need for appropriate product development platforms. Despite successfully capturing the microstructural evolution of aqueous foams, the complexity of current models renders them inadequate for pharmaceutical development. This review article will focus on the physics of foams and the attempts at optimizing them for sclerotherapy. This takes the form of a discussion of the most recent numerical and experimental models, as well as an overview of clinically relevant parameters. This holistic approach could contribute to better foam characterization methods that patients may eventually derive long term benefit from.

Results of polidocanol endovenous microfoam in clinical practice

BACKGROUND

Initial phase III clinical studies with polidocanol endovenous microfoam (PEM) demonstrated its safety and efficacy in the treatment of superficial venous reflux. In those studies, the primary outcome requirement was to assess the improvement in symptoms related to superficial venous disease. The goal of the present study was to evaluate the efficacy of PEM technology in routine clinical practice-specifically, the closure rates after treatment.

METHODS

We performed an observational study during which data were prospectively collected from 2 vein centers using an electronic database. Patients with CEAP (clinical, etiologic, anatomic, pathophysiologic) class ≥2 and symptomatic superficial axial reflux (great saphenous vein, anterior accessory saphenous vein, and small saphenous vein) were included and followed up prospectively. PEM was used to treat the saphenous vein and varicosities. The CEAP classification was used to classify chronic venous disease, and the venous clinical severity score (VCSS) was applied to measure the disease severity. Pain and discomfort were assessed using a visual analog scale, and the residual veins were assessed by physical examination.

RESULTS

PEM was used to treat superficial reflux in 60 patients. The CEAP classification was C2 for 32 patients, C3 for 14, C4 for 10, and C5 for 4 patients. The average pretreatment VCSS was 7.3. The saphenous vein diameter was 6.5 mm, and the average length was 31 cm. The average volume of PEM used to treat the saphenous veins was 9.3 mL. The closure rate at 3 and 6 months was 93% (54 of 58) and 93% (51 of 55), respectively. The VCSS had improved from 7.3 to 1.4. Complications included 1 case of deep vein thrombosis (1.7%), 5 patients (8.3%) with thrombophlebitis, and 4 patients (6.6%) with skin pigmentation.

CONCLUSIONS

PEM is safe and effective for the treatment of saphenous reflux and varicosities. The early closure rates using PEM were maintained at 6 months and are comparable to the results reported with nonthermal, nontumescent technologies and thermal tumescent technologies.

Venous Ablation

Chronic venous insufficiency is a common and a highly prevalent vascular disorder, that occurs as a result of venous reflux owing to defective venous valves, which in turn causes venous hypertension with significant symptom burden that can interfere with quality of life. Therapeutic strategy involves lowering the venous pressure by lifestyle changes, compression therapy, and conventional catheter-based thermal ablation and novel nonthermal, nontumescent techniques of ablating the affected veins.

Bleomycin Polidocanol Foam (BPF) Stability - In Vitro Evidence for the Effectiveness of a Novel Sclerosant for Venous Malformations

OBJECTIVE

This study investigated the in vitro stability of a novel sclerosant, bleomycin polidocanol foam (BPF), for venous malformation (VM) sclerotherapy.

METHODS

The study was designed with control groups treated with polidocanol (0.5%, 1%, and 3%) only. The experimental groups included 21 BPFs, which was made by dissolving bleomycin at seven different concentrations (0.1%-1.5%) in polidocanol (0.5%, 1%, and 3%). The Tessari method was used to prepare sclerosant foam with a liquid:gas ratio of 1:4 at room temperature in vitro. The foam stability was measured for each group. The decay process, one component of foam stability, was recorded with a camera. Foam decay process experiments were performed 10 times per group. The stability indices included drainage rate, drainage time, half life, and microscopic measurement of the foams (mean bubble diameter, minimum and maximum bubble diameters, wall thickness, and bubble diameter distribution).

RESULTS

Compared with the control groups, the half lives of BPFs mainly increased significantly with the addition of bleomycin (p < .001). BPF with 3% polidocanol and 0.1% bleomycin recorded the highest half life (246 ± 1.6 sec), and this group also achieved the smallest bubble diameter and wall thickness (69.9 μm and 5.80 μm) among the experimental groups. For the same polidocanol concentration, the bubble diameter and wall thickness increased when bleomycin was added.

CONCLUSION

Bleomycin concentrations account for different BPF stability. BPF stability mainly increased significantly with the addition of a small amount of bleomycin but this advantage was no longer apparent with increasing bleomycin dose.

Recent developments on foaming mechanical and electronic techniques for the management of varicose veins

Introduction: Varicose veins are a common disease, causing significant impairment of quality of life to afflicted individuals. Conventional surgery has represented the traditional treatment for years, with significant post-operative complications. By the end of the 20^th century, novel approaches had been developed to induce biochemical sclerosis into the treated vein in order to exclude it from blood circulation.Areas covered: Foaming techniques for treatment of varicose veins, both clinically-approved methods and those under experimental studies. A brief description of cavitation, which is the basis of microbubbles formation, and an overview of foam properties have been also provided, including a discussion on clinical efficacy and safety profile.Expert commentary: Foam sclerotherapy has rapidly gained popularity since it represents the most minimally invasive and cost-effective procedure in the short term. Several different methods of foam preparation have been described in literature. In general, the foam generation method may affect characteristics such as stability and bubble size distribution, which in turn affect the therapeutic action of foam itself. Therefore, the selection of a suitable foaming technique is of importance for treatment success. Future developments on foaming techniques are expected to make sclerotherapy, already an effective treatment, even safer and more versatile therapeutic procedure.

Global guidelines trends and controversies in lower limb venous and lymphatic disease: Narrative literature revision and experts' opinions following the vWINter international meeting in Phlebology, Lymphology & Aesthetics, 23-25 January 2019

Guidelines are fundamental in addressing everyday clinical indications and in reporting the current evidence-based data of related scientific investigations. At the same time, a spatial and temporal issue can limit their value. Indeed, variability in the recommendations can be found both among the same nation different scientific societies and among different nations/continents. On the other side, Garcia already published in 2014 data showing how, after three years in average, one out of five recommendations gets outdated (Martinez Garcia LM, Sanabria AJ, Garcia Alvarez E, et al. The validity of recommendations from clinical guidelines: a survival analysis. CMAJ 2014;186(16):1211–1219). The present document reports a narrative literature revision on the major international recommendations in lower limb venous and lymphatic disease management, focusing on the different countries’ guidelines, trends and controversies from all the continents, while identifying new evidence-based data potentially influencing future guidelines. World renowned experts’ opinions are also provided. The document has been written following the recorded round tables scientific discussions held at the vWINter international meeting (22–26 January 2019; Cortina d’Ampezzo, Italy) and the pre- and post-meeting literature search performed by the leading experts.

Efficacy Assessment of Ultrasound Guided Lauromacrogol Injection for Ablation of Benign Cystic and Predominantly Cystic Thyroid Nodules

Background

To assess the efficacy and safeness of ultrasound guided lauromacrogol injection for ablation of benign cystic and predominantly cystic thyroid nodules.

Methods

From July 2016 to July 2018, 102 patients with 107 nodules were treated with ultrasound guided lauromacrogol injections for ablation and 43 nodules completed at least 12 months follow-up. Nodules sonographic characteristics, volume changes before and after USG-LIA, and complications were evaluated.

Results

Mean nodule volume decreased from 17.27 ± 20.51 ml to 5.35 ± 14.68ml (P < 0.05), and the overall resolution rate (volume reduction rate > 50%) was 91.67% in purely cysts and 75.90% in predominantly cystic nodules at the last follow-up. Within 6 months after treatment, the volume of the target nodule at each follow-up was smaller than the previous one (P < 0.001 for all). However, there was no significant difference of volume change between the 6th month and the 12th month. No severe complications occurred in this study.

Conclusion

Ultrasound guided lauromacrogol injection for ablation is an effective and safe treatment modality in both purely cystic and predominantly cystic thyroid nodules.

Physical Vein Models to Quantify the Flow Performance of Sclerosing Foams

Foam sclerotherapy is clinically employed to treat varicose veins. It involves intravenous injection of foamed surfactant agents causing endothelial wall damage and vessel shrinkage, leading to subsequent neovascularization. Foam production methods used clinically include manual techniques, such as the Double Syringe System (DSS) and Tessari (TSS) methods. Pre-clinical in-vitro studies are conducted to characterize the performance of sclerosing agents; however, the experimental models used often do not replicate physiologically relevant physical and biological conditions. In this study, physical vein models (PVMs) were developed and employed for the first time to characterize the flow behavior of sclerosing foams. PVMs were fabricated in polydimethylsiloxane (PDMS) by replica molding, and were designed to mimic qualitative geometrical characteristics of veins. Foam behavior was investigated as a function of different physical variables, namely (i) geometry of the vein model (i.e., physiological vs. varicose vein), (ii) foam production technique, and (iii) flow rate of a blood surrogate. The experimental set-up consisted of a PVM positioned on an inclined platform, a syringe pump to control the flow rate of a blood substitute, and a pressure transducer. The static pressure of the blood surrogate at the PVM inlet was measured upon foam administration. The recorded pressure-time curves were analyzed to quantify metrics of foam behavior, with a particular focus on foam expansion and degradation dynamics. Results showed that DSS and TSS foams had similar expansion rate in the physiological PVM, whilst DSS foam had lower expansion rate in the varicose PVM compared to TSS foam. The degradation rate of DSS foam was lower than TSS foam, in both model architectures. Moreover, the background flow rate had a significant effect on foam behavior, enhancing foam displacement rate in both types of PVM.

The leaves of Crataeva nurvala Buch-Ham. modulate locomotor and anxiety behaviors possibly through GABAergic system

Background

Crataeva nurvala Buch-Hum is an indigenous herb, extensively used in traditional medicines of the South Asian countries to treat inflammation, rheumatic fever, gastric irritation, and constipation. Despite this wide range of uses, very little information is known regarding its effects on the central nervous system (CNS). Therefore, this study evaluated the neuropharmacological properties of methanolic extract of Crataeva nurvala leaves (MECN) using a number of behavioral models in animals. This study also identified potentially active phytochemicals in MECN.

Methods

Following MECN administration (at 50, 100 and 200 mg/kg; b.w.) the animals (male Swiss albino mice) were employed in hole-cross test (HCT), open field test (OFT), and rota-rod test (RRT) to evaluate sedative properties, where anxiolytic activities were investigated using elevated plus maze (EPM), light dark box (LDB), and marble burying test (MBT). The involvement of GABAergic system was evaluated using thiopental sodium (TS)-induced sleeping time determination test. Moreover, colorimetric phytochemical tests as well as GC/MS-MS were also conducted to define the phytochemical constituents of MECN.

Results

MECN possesses sedative properties indicated through the dose-dependent inhibition of locomotor activities of the animals in HCT and OFT and motor coordination in RRT. MECN also exhibited prominent anxiolytic properties through decreased burying behavior in MBT, increased time spent and transitions in open arm of EPM, and increased time spent in light compartment of LDB. In addition, the treatments potentiated TS-mediated hypnosis indicating a possible participation of GABAergic system in the observed sedative and anxiolytic activities. Phytochemical screening of MECN revealed 48 different compounds in it. We reviewed and conceive that the sedative and anxiolytic effects could be due to the presence of neuroactive compounds such as phytol, D-allose, and α-Tocopherol in MECN.

Conclusion

The present study showed that MECN possesses sedative and anxiolytic potential which could be beneficial in treatment of anxiety and insomnia associated with different psychological disorders.