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

An Optical Method for Immediate Evaluation of Microfoam Stability in Foam Sclerotherapy

OBJECTIVES

The objective of our study was to develop an optical method that instantly evaluates the stability of sclerosing foam, which would enable early predictions of the clinical performance of the foam and reduce the occurrence of clinical side effects.

METHODS

Based on the principle of light scattering, we developed a method to optically test foam stability and verified it experimentally using sodium morrhuate (2 mL; 0.05 g/mL) and carbon dioxide. A self-made foam preparation instrument was used to achieve a preparation speed of 275 mm/s. The liquid-gas ratios were considered as 1:3, 1:4, and 1:5. Curves of illuminance with respect to the drainage rate and decay time were obtained. By fitting the curve, the relationship between foam half-life time (FHT) and foam decay was obtained. Thus, foam stability was evaluated using the initial illuminance value; the foam transfer time was approximately 3 s.

RESULTS

The experimental FHT varies between 205 and 232 s. Illuminance is exponentially related to drainage rate and linearly related with time. FHT can be expressed by the initial illuminance and illuminance curve fitting coefficients. The half-life of the foam decreases as the initial illuminance value increases, for the same sclerosing drug. The suitability of foam stability is determined by the position of the initial value in the chart.

CONCLUSION

Optical methods are feasible for evaluating foam stability over a short period of time. Clinically predicting the stability of freshly prepared foam can reduce number of incidences of further complications. This will promote the development of foam sclerotherapy and provide a basic understanding of the internal mechanical properties of foam.

A Modiied 3-Way Tap to Enhance the Stability and Uniformity of Sclerosant Foam

BACKGROUND

The Tessari method, mixing air with the sclerosant through a 3-way tap and 2 syringes, is the most widely used method to prepare foam in foam sclerotherapy. Uniform foam with smaller bubbles has great clinical significance for venous insufficiency. We aim to modify the traditional 3-way tap to produce more uniform and stable foam with smaller bubbles.

METHODS

The traditional 3-way tap was modified by inserting a porous film within its channel.

EXPERIMENT DESIGN

the foam was prepared with 2 mL polidocanol plus 8 mL air plus 0.05 mL hyaluronic acid; group 1, foam prepared with 20 quick passes through a traditional 3-way tap; and groups 2-7, foam prepared using the modified 3-way tap, with 10, 12, 14, 16, 18, and 20 quick passes, respectively. The uniformity of the foam was observed under optical microscopy, and the size of bubbles quantified using the Nano measurement software. The stability of the foam was evaluated using the foam half-life time.

RESULTS

The foam half-life times of groups 1-7 were 306.4, 257.4, 285.6, 304.4, 318.6, 330.2, 331.3 sec, respectively. The modified tap also produced a more uniform distribution of smaller bubbles (group 7) compared with traditional tap (group 1).

CONCLUSIONS

Modified 3-way tap enhanced the stability of the sclerosant foam, with a more uniform distribution of smaller bubbles.

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.

Consensus statement of the Italian society of colorectal surgery (SICCR): management and treatment of hemorrhoidal disease

Hemorrhoidal disease (HD) is the most common proctological disease in the Western countries. However, its real prevalence is underestimated due to the frequent self-medication.The aim of this consensus statement is to provide evidence-based data to allow an individualized and appropriate management and treatment of HD. The strategy used to search for evidence was based on application of electronic sources such as MEDLINE, PubMed, Cochrane Review Library, CINAHL, and EMBASE.These guidelines are inclusive and not prescriptive.The recommendations were defined and graded based on the current levels of evidence and in accordance with the criteria adopted by American College of Chest Physicians. The recommendations were graded A, B, and C.