Foam sclerotherapy techniques: different gases and methods of preparation, catheter versus direct injection

Modified Tessari Tourbillon technique for making foam sclerotherapy with silicone-free syringes

The longevity of foam made using sodium tetradecyl sulphate and gas (air or a CO2:O2 mixture) is increased significantly if silicone-free syringes are used over the normal syringes containing silicone oil lubrication. However, the plungers in silicone-free syringes start sticking after several passages when making foam for sclerotherapy, preventing the smooth injection of the resulting foam. We describe a three syringe technique which allows foam to be made using the Tessari Tourbillon 'three-way stopcock' principle between two syringes, but with the foam ending up in a third syringe which has not undergone multiple passages of the plunger. This allows a smoother injection of the resultant foam, which is particularly useful when injecting small diameter veins under ultrasound control.

Role of interventional radiologists in the management of lower extremity venous insufficiency

Lower extremity venous insufficiency affects over half of all women. Interventional radiologists should be aware of the clinical evaluation of women with venous insufficiency and classification of disease. Endovascular therapies available for treatment of lower extremity venous insufficiency include: endovenous laser ablation, radiofrequency endovascular ablation, and sclerotherapy. The interventional radiologist should be versed on which therapy to select in each clinical presentation and the procedural techniques. The authors review the role of the interventional radiologist in managing this lower extremity venous disorder.

Blockade of tubal patency following transcervical administration of polidocanol foam: initial studies in rhesus macaques

OBJECTIVE

To demonstrate the feasibility of polidocanol foam (PF) as a nonsurgical method of female permanent contraception using a nonhuman primate model.

STUDY DESIGN

Four groups of adult female rhesus macaques underwent either transcervical treatment with 5% PF directly into the uterine cavity, treatment with inert (methylcellulose, MF) foam or no treatment followed by removal of the reproductive tract for histologic evaluation. Untreated animals were included in Group 1 (n=3). Group 2 animals (n=4) were treated once with MF. Group 3 (n=7) received a single, and Group 4 (n=5) received multiple monthly treatments with PF; in these 2 groups, baseline tubal patency was assessed either laparoscopically by chromopertubation (CP) or by hysterosalpingography.

RESULTS

Group 1 (untreated) and Group 2 (MF) animals had normal tubal histology. In contrast, Group 3 and 4 females treated with PF showed evidence of tubal damage. In Group 4, bilateral tubal blockade was noted on CP after two (n=2) or three (n=3) treatments. Histologic analysis confirmed complete tubal occlusion (loss of epithelium, fibrosis) in three of these animals, and one showed significant tubal damage localized to the intramural segment. Nontarget (cervix, vagina, endometrium, ovary) reproductive tissues were unaffected. While similar tubal changes were observed after a single treatment (Group 3), endometrial hemorrhage was also noted as an acute change.

CONCLUSION

PF is a promising candidate agent for nonsurgical permanent female contraception. The histologic features of PF occlusion are confined to the intramural portion of the tube.

IMPLICATIONS

This study in rhesus macaques supports further development of transcervical administration of PF as a nonsurgical approach to permanent contraception. A nonsurgical method could reduce risks and costs associated with surgical female sterilization and increase access to permanent contraception.

Results from RCTs in Sclerotherapy: European Guidelines for Sclerotherapy in Chronic Venous Disorders*

Aim

Sclerotherapy is the targeted chemical ablation of varicose veins by intravenous injection of a liquid or foamed sclerosing drug. The treated veins may be intradermal, subcutaneous, and/or transfascial as well as superficial and deep in venous malformations. The aim of this guideline is to give evidence-based recommendations for liquid and foam sclerotherapy.

Methods

This guideline was drafted on behalf of 23 European Phlebological Societies during a Guideline Conference on 7th–10th May 2012 in Mainz. The conference was organized by the German Society of Phlebology.

Results

This guideline focuses on the two sclerosing drugs which are licensed in the majority of the European countries, Polidocanol (POL) and Sodium tetradecyl sulphate (STS). Other sclerosants are not discussed in detail. In this paper the results from recent RCTs in sclerotherapy are reviewed.

European guidelines for sclerotherapy in chronic venous disorders

Aim

Sclerotherapy is the targeted chemical ablation of varicose veins by intravenous injection of a liquid or foamed sclerosing drug. The treated veins may be intradermal, subcutaneous, and/or transfascial as well as superficial and deep in venous malformations. The aim of this guideline is to give evidence-based recommendations for liquid and foam sclerotherapy.

Methods

This guideline was drafted on behalf of 23 European Phlebological Societies during a Guideline Conference on 7–10 May 2012 in Mainz. The conference was organized by the German Society of Phlebology. These guidelines review the present state of knowledge as reflected in published medical literature. The regulatory situation of sclerosant drugs differs from country to country but this has not been considered in this document. The recommendations of this guideline are graded according to the American College of Chest Physicians Task Force recommendations on Grading Strength of Recommendations and Quality of Evidence in Clinical Guidelines.

Results

This guideline focuses on the two sclerosing drugs which are licensed in the majority of the European countries, polidocanol and sodium tetradecyl sulphate. Other sclerosants are not discussed in detail. The guideline gives recommendations concerning indications, contraindications, side-effects, concentrations, volumes, technique and efficacy of liquid and foam sclerotherapy of varicose veins and venous malformations.

Catheter-directed foam sclerotherapy for insufficiency of the great saphenous vein: occlusion rates and patient satisfaction after one year

OBJECTIVES

This study aims to describe a technique for catheter-directed foam sclerotherapy (CDS) of great saphenous vein (GSV) insufficiency and report occlusion rate and patient satisfaction after a single treatment.

METHODS

About 100 patients were included. The GSV was accessed at knee level. With the method of Tessari 10 mL sclerosant foam was made (2 mL 3% polidocanol and 8 mL air) and delivered along the GSV while the catheter was withdrawn. At two weeks and at one year after treatment the patients were evaluated.

RESULTS

CDS was successfully performed in 94 of the 100 patients. After one year, 84% of the patients were satisfied. Seventy percent of the GSV were completely occluded, 14% were partly occluded and 15% were recanalized. No serious side-effects occurred.

CONCLUSIONS

CDS is safe. Patient satisfaction is very satisfying and the occlusion rate is promising after a single treatment. Repeated treatments and technical development may achieve higher occlusion rates.

[Foam sclerotherapy. Uses and indications in dermatology and phlebology]

Foam sclerotherapy is a minimally invasive, effective technique for the treatment of varicoses up though venous malformations. This efficient therapy can be easily integrated in daily clinical practice and shows only minor side effects. It provides an alternative to invasive therapies like vein stripping, endovenous laser therapy or endovenous radiofrequency ablation, but without the need for anesthesia. The treatment can be performed in an outpatient setting and the patient is able to return quickly to everyday life.

An investigation of side-effects and efficacy of foam-based sclerotherapy with carbon dioxide or room air in the treatment of reticular leg veins: a pilot study

OBJECTIVES

In sclerotherapy, carbon dioxide (CO(2)) or room air can be employed by phlebologists for foam creation. We compared room air (RA) and carbon dioxide in treating reticular leg veins with foam sclerotherapy.

METHODS

Twenty patients were randomly treated with RA- or CO(2)-created sodium tetradecyl sulphate (STS) foam. Concentration and volume of STS, side-effects and efficacy were determined.

RESULTS

There was no difference in the efficacy, local side-effects or distant side-effects between RA and CO(2) foam in the treatment of reticular leg veins. The total volume of foam sclerosant required for treatment was greater with CO(2) compared with RA (P value = 0.01).

CONCLUSION

No differences were found in efficacy or side-effects between RA- and CO(2)-foam sclerotherapy for reticular leg veins. CO(2) foam's shorter half-life was hypothesized to be responsible for larger total volumes of CO(2) foam sclerosant.

Paradoxical embolism, stroke and sclerotherapy

Sclerotherapy has been associated with 13 published cases of stroke since 1994. Four earlier reports implicated liquid sclerosants while nine recent cases have followed foam sclerotherapy. This adverse event represents a very rare complication of a very popular procedure. Ten of the 13 reported patients recovered completely with no long-term sequelae. A right-to-left shunt and in particular a patent foramen ovale (PFO) was the most consistent risk factor. Paradoxical gas emboli were observed in the brain-supplying or the intra-cranial arteries of five patients with an immediate onset of stroke after foam sclerotherapy. Paradoxical clot embolism was suspected in three patients with a delayed onset of stroke and concurrent venous thrombosis. In the remaining five cases, which included two cases with an immediate onset after liquid sclerotherapy, no specific cause was identified. Patients with a past history of cryptogenic stroke or a long life history of recurrent classic migraine attacks (with aura) have a higher risk of neurological adverse events and may benefit from preoperative screening and percutaneous closure of PFO.

Principles and Technique of Foam Sclerotherapy and Its Specific Use in the Treatment of Venous Leg Ulcers

Invention of foam sclerotherapy has significantly changed the current phlebological practice. Compared with liquid sclerosants, obliterating foam is more efficient, especially for the closure of larger veins. This review discusses clinical aspects of foam sclerotherapy with a focus on its use for the treatment of venous leg ulceration, including the rationale for its use in the treatment of these chronic wounds, physicochemical mechanisms responsible for stability and disintegration of sclerosant foam, pathomechanism of neurologic adverse events seen after foam sclerotherapy, and techniques that can increase efficacy of this procedure and lower frequency of adverse events.

An investigation on the influence of glycerin on sclerosant foam stability

BACKGROUND

Foam sclerotherapy is an increasingly popular modality in the treatment of varicose veins. Foam stability varies according to foam composition, volume and injection technique.

MATERIALS AND METHODS

A disposable plastic connector was used to create foam from 0.50% sodium tetradecyl sulphate (STS) mixed with varying volumes of glycerin. As a measure of foam stability, the half liquid time was defined as the time required for half of the original volume of sclerosing solution to settle. Three recordings were determined for each of the three mixtures of sclerosant foam.

RESULTS

The time for sclerosing solution to settle to half of its initial volume was found to be 89 seconds for 0.50% STS alone, 117.7 seconds with the addition of 0.1 mL of 72% glycerin, and 114.7 seconds with the addition of 0.2 mL of 72% glycerin.

CONCLUSION

The small volumes of glycerin added to STS prolonged the half liquid time of STS foam up to 35%. As glycerin alone is unable to be foamed with the double-syringe system technique there may be a point at which further addition of glycerin has a negative effect on the half-life of foam.

Sodium tetradecyl sulphate foam stability prior to injection: factors affecting liquid reformation

Objective

To study the effect of sclerosant concentration, use of 5-µm filter, use of CO2 versus air and needle size on the stability of sodium tetradecyl sulphate (STS) foam and observe the dynamics of liquid reformation from foam within the syringe prior to injection.

Method

Observations of liquid reformation within the syringe following foam preparation using the Tessari method.

Result

Foam stability varies little with STS concentration between 0.5% and 3%. Needle size has little effect in this study. An in-line filter produces significantly more stable foam, and CO2 foam is significantly less stable than air foam. Liquid reformation is predictable and does not progress at a constant rate.

Conclusion

Regardless of the method and details of the foam produced, sclerotherapists should be aware of the dynamics and speed of foam degradation, and reconstitute foam at the first sign of liquid reformation, as this heralds the onset of rapid degradation of the foam. This is particularly relevant for rapidly deteriorating foam produced from CO2, or without the use of a filter.

Deactivation of sodium tetradecyl sulphate injection by blood proteins

OBJECTIVES

The aim of this work was to quantify the volume of blood required to deactivate 1 ml of 3% sodium tetradecyl sulphate (STS).

DESIGN

A series of experiments were performed where the concentration of STS remaining in a stock solution was measured after adding increasing volumes of blood protein solutions.

MATERIALS AND METHODS

Increasing volumes of bovine serum albumin, bovine erythrocytes and a mixture of both was added to a stock solution of STS. The BP manual titration method was used to measure the assay of the remaining STS.

RESULTS

The method was reproducible and increasing volumes of blood protein lowered the STS concentration in a linear fashion. Approximately 2 ml of a 4% blood protein solution deactivates 1 ml of 3% STS, which means approximately 0.5 ml of whole blood will deactivate 1 ml of 3% STS.

CONCLUSIONS

Sodium tetradecyl sulphate injection is deactivated by a relatively small volume of blood. The practical implication is that changes in technique to reduce the blood volume in larger veins and to introduce fresh aliquots of sclerosant along the length of the vein could improve the efficacy of sclerotherapy.