PMC5473085_01
T2-weighted MRI at initial presentation (a) showed silent microbleed in the genu of corpus callosum (arrow). AP (b) and lateral views (c) of preoperative right internal carotid angiography showed severe stenosis in the terminal portion of the right internal carotid artery (ICA) associated with the development of basal moyamoya vessels (arrow). Note the development of collateral pathway to the anterior cerebral artery through the ophthalmic artery
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F1
MRI demonstrated no lesion, T2-weighted MRI revealed a microbleed in the genu of corpus callosum [Figure 1a]. MRA showed the occlusion of left ICA and severe stenosis of the terminal portion of right ICA and its branches. The terminal portion of the right ICA and its main branches were severely stenotic, associated with basal moyamoya vessels (stage 3; Figure 1b and c). 15O-gas positron emission tomography (PET) detected no hemodynamic insufficiency.
T2-weighted MRI taken 6 months later demonstrated two de novo microbleeds in the right deep temporal lobe adjacent to the temporal horn and the right frontal lobe (arrows)
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F2
Although she developed no cerebrovascular episodes, T2-weighted MRI revealed two de novo microbleeds in the right deep temporal lobe adjacent to the temporal horn and the right frontal lobe [Figure 2].
AP (a) and lateral views (b) of postoperative right common carotid angiography showed well developed collaterals through the external carotid system. Note a marked deminishment of basal moyamoya vessels after surgery
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F3
Right common carotid angiogram demonstrated well-developed surgical collaterals through both direct and indirect bypass and significant diminishment of moyamoya vessels [Figure 3a and b].
T2-weighted MRI taken 7 years after right superficial temporal artery to middle cerebral artery anastomosis and indirect bypass showed no newly developed microbleeds
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F4
She has been free from any cerebrovascular events, and serial MR examinations have shown no de novo microbleeds for the last 7 years after surgery [Figure 4].