Evaluation of magnetic resonance angiography with selective maximum intensity projection in patients with childhood moyamoya disease.

To determine whether magnetic resonance angiography with selective maximum intensity projection can facilitate the detection of cerebral moyamoya vessels in patients with childhood moyamoya disease, six patients with moyamoya disease (6 to 9 years old) and ten controls (4 to 16 years old) were evaluated by means of high resolution magnetic resonance angiography (matrix 512x384) with/without selective maximum intensity projection, and conventional angiography. In the patients with moyamoya disease, moderate or marked moyamoya vessels were detected but underestimated in 2/12 hemispheres on magnetic resonance angiography without selective maximum intensity projection. On magnetic resonance angiography with selective maximum intensity projection, moyamoya vessels were correctly assessed in 11/12 hemispheres (92%). In the controls, bilateral mild moyamoya vessels were detected in eight of 20 hemispheres (four of ten patients, under 7 years old), which were compatible with normal lenticulostriate arteries. Magnetic resonance angiography with selective maximum intensity projection is an accurate modality for assessing moyamoya vessels in moyamoya disease.