Sclerotherapy with Adjunctive Stasis of Efflux (STASE) in Venous Malformations: Techniques and Strategies

Abstract

Venous malformations are very commonly encountered in interventional radiologic practice. Indications for therapy are clearly defined based on the lesion's impact on patient's quality of life. Screening laboratory coagulation studies in patients with historical or lesion morphologic risk factors often reveal abnormal coagulation parameters consistent with localized intravascular coagulation or more severe coagulopathic states. These may require chronic or periprocedural medical management to avoid potentially life-threatening disseminated intravascular coagulation or other thromboembolic phenomena. Once a multidisciplinary decision to treat a venous malformation is made, one must decide between percutaneous and/or surgical techniques. Sclerotherapy with adjunctive stasis of efflux (STASE) techniques have become the mainstay of therapy for most venous malformations as they are well-tolerated and effective. STASE techniques work primarily by (i) the administration of sclerosant(s) exerting an inhibitory and/or endotheliocidal effect on venous malformation endothelium leading to thrombosis, involution, and fibrosis, and secondarily via adjunctive outflow occlusion using any combination of local compression, balloons, gelatin, coils, laser, radiofrequency, or adhesives to improve sclerosant penetration and dwell-time in the lesion. Adhesives alone can fill the lesion to facilitate surgical resection in some cases. Common sclerosants in modern practice include sodium tetradecyl sulfate, bleomycin, polidocanol, ethanol, and hypertonic saline. Most agents can be given directly in unmodified or "neat" form or can be mixed with a gas to form a sclerofoam or embolic such as gelatin to form a sclerogel. Choice and method of sclerosant delivery in each patient is based on the intraluminal lesion volume, architecture, vital structure proximity, agent toxicity, viscosity, and level of experience of the interventional radiologist with that particular agent. Multi-session STASE therapy usually reduces symptoms of chronic pain or mass with low risk of known complications of skin or nerve impairment, compartment syndrome, hemoglobinuria, deep venous thrombosis, or pulmonary phenomena.

Management of Venous Malformations

“…Such methods include external compression (manually or by use of a sterile tourniquet, endovascular balloon occlusion, injection of glue, percutaneous ligation, and/or deployment of plugs or coils). 25 Endovascular coils or plugs are commonly placed in large outflow veins with appropriate landing zones (►Fig. 5a-c).…”

Vascular anomalies: special considerations in children

“…In these cases, venous outflow obstruction during the procedure should be considered. This may simply be manual by extrinsically placing pressure over the outflow tract or it may be more sophisticated by using glue or coils to internally obstruct the outflow vessels (Legiehn 2019;Chewning et al 2018) (Fig. 6).…”

Image-Guided Percutaneous Injection Sclerotherapy of Venous Malformations

“…Increasing the "dwell time" is desirable here [4,5,111], by using foam [11,42], mixing the drug with lipiodol [112,113], and using ethibloc [102], ethylcellulose [48], or ethanol-gel [49]. Tourniquet, pneumatic cuff, US probe pressure, or manual compression can be used to compress the veins, however, with the risk of overdistension of the VM and extravasation and/or sudden release of sclerosant bolus or thrombus into circulation after the release of the tourniquet [112].…”

“…Tourniquet, pneumatic cuff, US probe pressure, or manual compression can be used to compress the veins, however, with the risk of overdistension of the VM and extravasation and/or sudden release of sclerosant bolus or thrombus into circulation after the release of the tourniquet [112]. New tools like nBCA, EVOH, pushable or detachable coils, Amplatzer plugs, and intravenous balloon occlusion can all be used alone or in combination [4,5,29,93,111,112]. nBCA is a highly versatile tool; however, multiple punctures and delivery catheters may be needed.…”

“…nBCA is a highly versatile tool; however, multiple punctures and delivery catheters may be needed. In VMs, nBCA may be used to block the connecting veins and the dysplastic channels, and to cause an intralesional partial embolic occlusion of the venous channels which are subsequently filled with ethanol or foam [111] (Fig. 18).…”