Histopathological studies on spontaneous vault Moyamoya and revascularized collaterals formed by encephalomyosynangiosis

Two topics concerning the leptomeningeal vessels are discussed. The first portion indirectly proves that angiographic ‘vault Moyamoyaʹ consists of dilated preexisted vessels rather than newly-formed vessels, using morphometric analysis. The second portion presents a 67 year old autopsied case with Moyamoya disease who underwent encephalomyosynangiosis (EMS). Collateral vessels formed by EMS are histopathologically identified.