Abstract TP575: Amyloid Accumulation Evaluated With Pib Pet in Patients With Cerebral Amyloid Angiopathy

Abstract

Purpose: Cerebral amyloid angiopathy (CAA) is a disease with deposition of amyloid beta protein to meninges or intracerebral vessel walls. CAA is known as a cause of cerebral hemorrhage or subarachnoid hemorrhage occurring most frequently in the occipital lobe. CAA is usually accompanied with Alzheimer's disease, which shows specific pattern of amyloid accumulation. In this study we evaluated the distribution of the amyloid deposition in CAA patients using PIB-PET. Methods: Five patients, 3 males and 2 females, who developed cerebral hemorrhage or subarachnoid hemorrhage and clinically diagnosed as CAA were evaluated. Age of the patients was 28 - 74 years old. To detect amyloid accumulation, we injected 250-350mBq or 400-500mBq of [11C]PiB, followed by 60 minutes or 70 minutes dynamic scan using Eminence B PET camera (Shimadzu Corporation). Results: PIB accumulation was detected predominantly in the frontal lobe, parietal lobe, and lateral temporal lobe, but much less in the occipital lobe. The distribution of PIB accumulation was mostly similar to that in patients with Alzheimer disease. Little accumulation in the occipital lobe may reflect apparent effects of intracerebral hemorrhage. Conclusion: In most CAA patients, the examination by PIB-PET fails to detect amyloid deposition in the vessel walls of the occipital lobes. Instead, it more frequently reflect intracerebral amyloid deposition of accompanying Alzheimer's disease.