Utility of Venous Outflow Control Techniques in Low-Flow Vascular Malformation Sclerotherapy: A Case-Based Review

The crucial aspects of sclerotherapy are to achieve an adequate dwell time with endothelium and to limit the egress of sclerosant into the circulation: both issues could be addressed if the optimal means to control the venous malformation (VM) venous outflow was known. Medical literature from 1984 to August 2024 about sclerotherapy of vascular malformations was reviewed; all articles adopting and describing in technical details a stop-flow technique were considered and analyzed. Multiple outflow control techniques have been identified and categorized into 4 classes, described in technical details and discussed, illustrating for each a case performed in the authors' center. Lastly, a practical workflow was developed. The choice of venous embolization technique should be tailored to the specific VM type and location to maximize therapeutic effects while minimizing adverse events.