Sunday 15 July 2012

Moyamoya Disease MRI

A 31 yo known case of recurrent episodes of ishemia under evaluation.MRI study brain Axial FLAIR image of brain with non contrast 3 D TOF MR Angiography shows:
Bilateral cortical border zone infarcts.
Severe stenosis involving intra cranial portions of both the ICAs. MCAs not visualised along with its cortical branches. Distal portion of PCAs not visualised along with its cortical branches. Multiple vessels from proximal portion of PCAs are the thalamo striate perforators giving is so called Puff of Smoke appearance contributing to basal cerebral anastomotic or collateral network.

Moyamoya disease 

A bilateral steno occlusive disease of the intra cranial internal carotid artery.
Moyamoya is a Japanese word for a "puff" or "cloud of smoke" , and it has been used to refer to an extensive basal cerebral network of small anastomotic vessels at the base of the brain around and distal to the circle of Willis secondary to segmental stenosis or occlusion of the terminal parts of both internal carotid arteries.  The basal vascular network is contributed by lenticulostriate, chorioidal, thalamoperforating, premammilary and thalamogeniculate arteries, as well by to unnamed branches arising directly from the circle of Willis and meningeal arteries via ECA.
Pseudo aneurysms and micro aneurysm are well reported along these collaterals and circle of Willis. Pathogenesis of MD is not well understood. Various theories of inflammatory and immunologic mechanisms remain unproven. Very high concentration of basic fibroblast growth factor (bFGF) with high angiogenic activity in Csf samples of patients typical imaging findings of Moyamoya disease. There are strong evidences to support hereditary and familial factors especially among the Japanese.

Clinical manifestations of MD includes secondary to ischemia and or bleed. Ischemic symptoms common in children. Infarcts are more common along cortical border zones. Intracranial bleed in the form of subarachnoid bleed,  intra parenchymal or intraventricular bleed common in adults. Causes of intracranial haemorrhage in MD are rupture of dilated fragile collaterals or rupture of aneurysms along the circle of Willis and basal cerebral network of collaterals.

Reference: MOYAMOYA DISEASE: CLINICAL AND ANGIOGRAPHIC FEATURES Dragan Stojanov ,  Petar Bošnjaković,  Zoran Milenković, Nebojša Stojanović CLINICAL FEATURES OF MOYAMOYA DISEASE yong seung Hwang,

Other cases of Moya moya disease:
Moyamoya disease DSA 

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