Abstract 166: 34‐Year‐Old Male with Moyamoya Syndrome and Occipital AVM and Possible Wyburn‐Mason Syndrome

Moyamoya Syndrome (MMS) is believed to be caused by the formation of angiogenic factors and hemodynamic stress leading to a development of neovascularization. While there is typically no association between MMS and AVMs, there have been unique instances of simultaneous occurrences. Here, we present a 34 year‐old male with a known history of a left parieto‐occipital AVM who was stroke activated for right face and arm numbness and tingling. DSA found L‐ICA terminus occlusion affecting the L‐MCA M1 segment; this was accompanied by neovascularization of the L‐M2 segment by means of collateral flow from the L‐ophthalmic artery and L‐internal maxillary via the L‐ECA.