Cerebral amyloid angiopathy presenting as nonhemorrhagic diffuse encephalopathy: neuropathologic and neuroradiologic manifestations in one case

Abstract

A case of cerebral amyloid angiopathy is presented with MR imaging findings of high intense signal on T2-weighted sequences at the level of the white and gray matter of both hemispheres in the absence of neuroradiologic signs of cerebral hemorrhage. The biopsy specimen revealed deposition of amyloid in the walls of the intracranial arterial branches and focal ischemic changes and gliosis in the gray and white matter. We consider this presentation to be very unusual in patients affected by cerebral amyloid angiopathy.

fig 1.

Images obtained at the time of the first hospital admission. Axial view turbo spin-echo T2-weighted sequence. A, and B, Diffuse high intensity signal involving the cortex and the white matter of the right temporo-parieto-occipital region. Note also the involvement of the right frontal and left parieto-occipital regions. C, High intense signal can be seen in the occipital lobes bilaterally, involving both the gray and white matter.

fig 2.

Histopathologic examinations of the lesions. A, Hematoxylin and eosin stain. Vessel walls are thickened by an amorphous eosinophilic substance, and the lumen of the vessel is partially occluded. B, Immunohistochemistry for glial fibrillary acidic protein shows perivascular gliosis. C, Immunohistochemistry for β-amyloid shows the presence of amyloid deposits in the vessel walls.

fig 3.

Images obtained at the 1-year follow-up examination. A, and B, Axial view spin-echo T2-weighted sequence. High intense signal is present in the gray and white matter of the right frontal lobe and of both parietal lobes. Note that compared with figure 1, there is progression of the disease in the left parietal lobe. The right parietal lobe, on the contrary, looks less involved. C, Axial view spin-echo T2-weighted sequence. The lesion on the left is involving also the temporal lobe. D, Axial view fluid-attenuated inversion recovery sequence obtained at the same level as that shown in A. The parietal lobes are diffusely hyperintense. High intensity signal is also present in the right frontal lobe. The right parietal lobe appears less involved than on the previous MR image. E, Axial view fluid-attenuated inversion recovery sequence obtained at the same level as that shown in B. The parietal lobes are diffusely hyperintense. High intensity signal is also present in the right frontal lobe. The right parietal lobe appears less involved than on the previous MR image. F, Axial view fluid-attenuated inversion recovery sequence obtained at the same level as that shown in C. The parietal lobes are diffusely hyperintense. High intensity signal is also present in the right frontal lobe. The right parietal lobe appears less involved than on the previous MR image. G, Infused axial view spin-echo T1-weighted sequence. There is no evidence of abnormal contrast enhancement in the diseased regions. H, Infused axial view spin-echo T1-weighted sequences. There is no evidence of abnormal contrast enhancement in the diseased regions.