Constructive interference in steady state imaging of moyamoya disease.

The diagnostic accuracy of three-dimensional constructive interference in steady state (CISS) magnetic resonance (MR) imaging was evaluated for the assessment of idiopathic moyamoya disease. Six consecutive patients underwent MR angiography, CISS imaging, and digital subtraction angiography. MR angiography and CISS imaging visualization of the steno-occlusive changes in the distal internal carotid arteries and the development of moyamoya vessels in the basal cistern were compared to the results obtained by digital subtraction angiography. MR angiography revealed the steno-occlusive changes correctly in nine and overestimated the changes in three of 12 hemispheres examined. CISS imaging showed the steno-occlusive changes defined as decreased caliber of the internal carotid artery correctly in two, underestimated the changes in nine, and overestimated the changes in one of the 12 hemispheres. MR angiography detected moyamoya vessels correctly in five and underestimated the vessels in seven of the 12 hemispheres. CISS imaging revealed the moyamoya vessels correctly in 10, underestimated the vessels in one, and overestimated the vessels in one of the 12 hemispheres. CISS imaging can supplement MR angiography in the non-invasive diagnosis of moyamoya disease, especially for the evaluation of moyamoya vessels.