Injectable chitosan hydrogel effectively controls lesion growth in a venous malformation murine model

PURPOSE

The purpose of this study was to evaluate the safety and efficacy of intralesional injection of chitosan hydrogel (CH) combined with sodium tetradecyl sulfate (STS) to sclerose and embolize venous malformations (VMs) by comparison with 3% STS foam and placebo in a mouse model.

MATERIALS AND METHODS

Subcutaneous VMs were created by injecting HUVEC_TIE2-L914F cells, mixed with matrigel, into the back of athymic mice (Day [D] 0). After VM-like lesions were established at D10, 70 lesions were randomly assigned to one of six treatment groups (untreated, saline, 3% STS-foam, CH, 1% STS-CH, 3% STS-CH). For 3% STS-foam, the standard Tessari technique was performed. VMs were regularly evaluated every 2-3 days to measure lesion size until the time of collection at D30 (primary endpoint). At D30, VM lesions including the matrigel plugs were culled and evaluated by histological analysis to assess vessel size, chitosan distribution and endothelial expression. One-way analysis of variance (ANOVA) test was performed to compare quantitative variables with normal distribution, otherwise Kruskal-Wallis test followed by pairwise comparisons by a Wilcoxon rank sum test was performed.

RESULTS

All VMs were successfully punctured and injected. Six VMs injected with 3% STS-CH showed early skin ulceration with an extrusion of the matrigel plug and were excluded from final analysis. In the remaining 64 VMs, skin ulceration occurred on 26 plugs, resulting in the loss of three 3% STS-foam and one 1% STS-CH plugs. Both chitosan formulations effectively controlled growth of VMs by the end of follow-up compared to untreated or 3% STS-foam groups (P < 0.05). Vessel sizes were smaller with both CH formulations compared to untreated and saline groups (P < 0.05). Additionally, there were smaller vascular channels within the 1% STS-CH group compared to the 3% STS-foam group (P < 0.05).

CONCLUSION

Chitosan's ability to control the growth of VMs suggests a promising therapeutic effect that outperforms the gold standard (STS-foam) on several variables.

Postsclerotherapy compression: A systematic review

BACKGROUND

Compression after sclerotherapy is commonly used, although the evidence base for this practice is unclear. This study aims to summarize and assess the evidence for compression therapy after sclerotherapy to inform clinical practice.

METHODS

A systematic review was performed according to PRISMA guidelines via Medline and EMBASE databases (1946 to December 31, 2019) by two reviewers. Full-text, English-language studies comparing compression type and/or duration in adult chronic venous disease patients undergoing liquid or foam sclerotherapy were included.

RESULTS

Nine studies were identified: five using liquid sclerotherapy, three foam sclerotherapy and one using both. Studies had short follow-up periods (6-24 weeks) and reported on clinical outcomes, quality of life, side effects and complications. In C1 patients undergoing liquid sclerotherapy, any duration of stocking use significantly decreased telangiectasia and reticular vein number and size compared with no compression. No significant difference in clinical symptoms or quality of life was seen when comparing compression duration after liquid or foam sclerotherapy in tributary or truncal veins in C2 to C6 patients. Greater superficial vein resolution was seen with stockings compared with bandages in C2 patients undergoing liquid sclerotherapy to tributary veins. A comparison of stockings vs bandaging revealed differing thrombophlebitis rates but no significant difference in pigmentation. In C2 to C6 patients undergoing foam sclerotherapy, use of 35 mm Hg stockings significantly improved post-treatment symptoms compared with 23 mm Hg stockings. This review was limited by heterogeneity of outcome measurements and the variety of comparisons between compression types and durations.

CONCLUSIONS

Postsclerotherapy compression may have beneficial clinical outcomes at short-term follow-up; however, evidence is lacking regarding its type, class, length, and duration. Further trials are required to guide the optimal management of postsclerotherapy patients.

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.