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FIG 2. 72 hours after the onset of stroke symptoms in a patient with vasculitis.
A, T2-weighted MR image shows bilateral posterior watershed lesions (arrows).
B, The ADC map also shows bilateral posterior watershed lesions (arrowheads), but both lesions are larger than those seen on T2-weighted images (A).
C, The rMTT map shows hypoperfusion (hyperintensity) of both posterior watershed territories (arrowheads).
D, The rCBV map shows only a left-sided lesion (arrow), including posterior watershed and part of the posterior cerebral artery territory (arrowhead).
E, The 16-month follow-up T2-weighted image confirmed small left posterior watershed infarction (arrow) and new infarction at the territory of the left posterior cerebral artery (arrowhead), which was not apparent on initial T2-weighted image (A) or ADC map (B) but was partially visible on rCBV map (D). The abnormality of the right posterior watershed area initially demonstrated on the T2-weighted image (A) and ADC map (B) did not develop into infarction (E). It was accurately predicted by the rCBV map whereas the T2-weighted image and ADC map were falsely positive. The left posterior cerebral artery infarction (arrowhead) was partially diagnosed by the rCBV map, but the ADC map and T2-weighted images were falsely negative.
(Permission granted from the AJNR 20:983–989, June/July 1999.)
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