Advances in molecular imaging for the diagnosis of dementia.

Tohoku University, Pharmacology, Sendai, Japan.
Expert Opinion on Medical Diagnostics 11/2009; 3(6):705-16. DOI: 10.1517/17530050903133790
Source: PubMed

ABSTRACT Background: There is an urgent need for early diagnosis and treatment of dementia to ease caregiver burden and medical costs associated with the increasing number of affected patients. Molecular imaging with target-specific ligands is contributing to the early diagnosis of dementia and the evaluation of anti-dementia therapy. Objective: This article reviews recent advances in the molecular imaging field applied to dementia. To illustrate the utility of molecular imaging in the clinical management of dementia, results from recently published papers using new imaging probes are compared with those from conventional imaging strategies. Conclusion: The recent development of β-sheet binding agents including FDDNP, PIB, SB-13, BF-227 and BAY94-9172 enables the non-invasive detection of amyloid deposition in the brain. These agents would be useful for the early and accurate diagnosis of Alzheimer's disease, patient selection for disease-modifying therapeutic trials and monitoring the effect of anti-amyloid therapy. Also, monitoring neurotransmitter function contributes to the differential diagnosis of dementia and refinement of treatment protocols. New targets for molecular imaging are focusing on protein misfolding diseases associated with the neurotoxic deposition of aggregated tau, α-synuclein and prion proteins.

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