Efficacy and Safety Analysis of More Stable Foam and Ordinary Foam Based on Polylauricol in the Treatment of Head and Neck Venous Malformations: a Prospective, Randomized and Controlled Study

Foam sclerotherapy is an effective method for the treatment of venous malformations in head and neck, which has been widely used in the world in recent years. The foam hardener is a kind of uniform microfoam formed by the mixture of surfactant liquid hardener and a certain proportion of gas. The microfoam has fluidity and can be injected into the cavity of venous malformation, the foam can replace the blood in the Lacuna, and can expel the blood, the foam occupies the lesion lacuna, makes the hardener be diluted by the blood to the minimum degree, so that the function concentration of the hardener can be guaranteed, the foam can contact the endothelial cells of venous malformations, acting as the contact betthe investigatorsen the liquid hardener and the endothelial cells, and the foam is less mobile than the liquid hardener, so the foam can be replaced by the blood for a longer time than the liquid hardener, sclerosants can affect endothelial cells for a long time. The disadvantage of liquid hardeners is that they are diluted by blood, leading to an insufficient level of desired effect at the injection site and into the normal venous system. In contrast, foam hardeners replace blood rather than mix with it and occupy the interior of blood vessels. The foam blocks blood flow, increasing the time of contact betthe investigatorsen the Hardener and the vessel wall. Foam hardeners are more effective than liquid hardeners in treating VMS. There are many factors that affect the therapeutic effect of foam hardening, such as the types of hardeners and the stability of foam, among which the stability of foam is one of the key factors that affect the therapeutic effect of foam hardening, the stability of the foam is affected by many factors, such as the type, concentration, liquid-gas ratio, gas type and temperature of the Hardener. The half-life, the time it takes for a foam to reduce its volume to half its original volume (half-volume) , is widely used to assess foam stability. According to the study, the half-life of 1% poly (cinnamyl alcohol-RPol(POL) foam with a liquid-to-gas ratio of 1:4 was 142.8(64.32) seconds, in this study, the half-life of the foam made from 1% POL containing 0.05% hyaluronic acid (HA) was 390.4(613.06) seconds, human blood contains a certain amount of HA, according to the literature reported that 0.05% concentration of HA injected into human blood is safe, so this more stable foam preparation method was patented, and published in international journals. Our team used more stable POL foam to treat head and neck VMs, which was found to be safe and effective by retrospective study. The results of this study have been published in international journal. It has also been reported that glycerol added to the sclerosing agent polydocanol or sodium tetradecyl sulfate can enhance the stability of the foam. The foam produced by glycerol has been used in the treatment of VMS of the head and neck for more than 2 years, and that a more stable bubble might work better. Therefore, whether the more stable hardening agent foam will have better therapeutic effect and whether its safety is different from that of ordinary foam, there is only conjecture and no clear evidence to ansthe investigatorsr this question. Therefore, on the basis of the previous research, a prospective randomized clinical trial was conducted to evaluate the efficacy and safety of polycinol foam in the treatment of venous malformations in the head and neck region, this trial may provide better treatment options and evidence for head and neck VMs.