Fig 1.

Imaging of CAA/ACNS at presentation and after 9 months of therapy with pathologic correlation.

A, FLAIR coronal image shows increased signal intensity with mass effect on the adjacent sulci and lateral ventricles in the right occipitotemporal region.

B, Diffusion-weighted axial image shows no restricted diffusion.

C, T1-weighted axial contrast-enhanced image shows decreased signal intensity without contrast enhancement.

D, Probe-press, single voxel (2 cm³ [TE = 135]) centered on the region of abnormality shows normal spectra and ratios.

E, Hematoxylin and eosin slide shows a blood vessel (arrow) with surrounding inflammation and multinucleated giant cells (arrowheads).

F, Immunohistochemistry with a beta-amyloid specific antibody demarcates the vessel wall (arrowheads). Both vessels are surrounded by a mononuclear inflammatory infiltrate (hematoxylin counter-stain).

G, FLAIR coronal image obtained 9 months after presentation shows significant resolution of previously seen tumafactive lesion in the right occipitotemporal region.

H, FLAIR axial image obtained 9 months after presentation shows increased signal intensity in the right and left temporal regions (arrows).