Infarctions and non-invasive diagnosis in moyamoya disease: two case reports.

An 31-year-old female and a 32-year-old male had clinical signs and angiographical confirmation of adult Moyamoya disease (MMD). Bilateral carotid siphon (C1), middle cerebral artery (M1), and anterior cerebral artery (A1) stenoses were diagnosed by means of transcranial Doppler sonography (TCD) and visualized during angio Magnetic Resonance Imaging (angio-MRI). In the woman, a 'rete mirabile' of dilated and tortuous lenticulostriate arteries could be visualized during proton weighted and T1-weighted MRI sequences. CO2-dependent vasomotor reactivity was bilaterally reduced and completely exhausted in the territory of right middle cerebral artery in both patients. Cerebral perfusion reserve, defined as the ratio of cerebral blood flow (CBF) to cerebral blood volume (CBV) was assessed by SPECT, and was found to be dramatically reduced in the anterior region of the male patient. Both patients had bilateral small subcortical infarctions in the corona radiata. TCD and MRI are important noninvasive techniques for a preliminary diagnosis of Moyamoya disease. Infarctions in Moyamoya disease may be hemodynamically produced low-flow infarctions.