To determine the correspondence between uptake of Pittsburgh Compound B (PiB) in life and measures of β-amyloid (Aβ) in postmortem tissue analysis.Patient
A 76-year-old man with a clinical diagnosis of dementia with Lewy bodies underwent fluorodeoxyglucose 18F and PiB positron emission tomographic brain scans. Imaging revealed marked region specific binding of PiB and abnormal fluorodeoxyglucose uptake.Intervention
Autopsy was performed 3 months after the PiB scan.Results
Autopsy confirmed the clinical diagnosis; in addition, there was severe cerebral amyloid angiopathy and only moderate numbers of parenchymal Aβ plaques. Biochemical measures revealed a positive correlation between Aβ levels and regional PiB binding.Conclusion
This report confirms that PiB detects Aβ in the living patient and demonstrates that amyloid deposited as cerebral amyloid angiopathy can be the dominant source of signal.