Magnetic resonance imaging. (A) Axial diffusion-weighted image showing an acute infarction in the territory of the right paramedian pontine artery that extends to the basal surface. (B) Sagittal digital subtraction angiography image showing moderate stenosis (<50%) in the basilar artery. Axial (C) and sagittal (D) non-contrast-enhanced three-dimensional fast spin-echo T1 imaging with variable flip angles (Cube T1) showing a plaque in the dorsal wall of the basilar artery (arrow). The orifice of the paramedian pontine artery is shown by the arrowhead. Sagittal (E) and coronal (F) three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) showing the right paramedian pontine artery (arrowhead). The ischemic lesion appears as a hypointense signal on the Cube T1 (C and D) and a hyperintense signal on the 3D-FIESTA (E).