ABSTRACT
In 2003, Puig proposed a modified phlebographic classification system. Type I venous malformation (VM) was defined as an isolated malformation without peripheral venous drainage. Type II was a VM that drains into normal veins. Type III was a VM that drains into dysplastic veins. Type IV was a VM that represents a venous dysplasia. Puig classification is well correlated with percutaneous sclerotherapy results. Types I and II show good therapeutic response to sclerotherapy because the sclerosing agent can be confined within VM for a sufficient time, and the sclerosant washout into the normal venous system can be minimized. Type I and II VMs showed higher cure rates with a lower number of treatment sessions. However, it is difficult for enough sclerosing agent to stay in type III and IV VMs, which leads to less therapeutic response. Furthermore, type III and IV VMs have risks for embolic material spillage into the normal venous system, which gives rise to systemic complications. Therefore, the rate of exclusion from sclerotherapy is higher (up to half of patients) in type III and IV VMs. This phlebographic classification system can be applied to simple VMs on International Society for the Study of Vascular Anomalies classification 2014 but not for the combined types.
