Objective: This study aims to explore whether early-phase ¹⁸F-N-(3-fluoropropyl)-2β-carboxymethoxy-3β-(4-iodophenyl) nortropane (¹⁸F-FP-CIT) positron emission tomography (PET) images can predict β-amyloid positivity on ¹⁸F-florbetaben (¹⁸F-FBB) PET scans in patients with dementia with Lewy bodies (DLB).

Background: Early-phase ¹⁸F-FP-CIT PET images (i.e., images acquired within the first 10 min after ¹⁸F-FP-CIT injection in a single PET session when diagnosing PD) reflect cerebral perfusion that may have significant associations with brain β-amyloid load.

Method: We reviewed the medical records of 78 patients with DLB who underwent dual-phase ¹⁸F-FP-CIT PET scans and ¹⁸F-FBB PET scans upon initial diagnosis. Patients were divided into two groups based on ¹⁸F-FBB PET images: amyloid-positive group (n = 49) and amyloid-negative group (n = 29). We compared regional uptake in the early-phase ¹⁸F-FP-CIT PET images between the two groups. We further performed a linear discriminant analysis (LDA) to predict β-amyloid deposition based on the standard uptake value ratios (SUVRs) of each region of interest on the Desikan–Killiany atlas.

Results: The amyloid-positive group exhibited decreased uptake in the superior parietal, supramarginal, inferior parietal, precuneus, middle temporal, and inferior temporal cortices and increased uptake in the pallidum and amygdala compared to the amyloid-negative group. The LDA prediction model demonstrated that SUVRs of the precuneus and pallidum optimally distinguished the amyloid-positive group from amyloid-negative group.

Conclusions:

Conclusion: The present study demonstrated that decreased regional uptake in the precuneus and increased regional uptake in the pallidum on the early-phase ¹⁸F-FP-CIT PET images were associated with β-amyloid deposition in patients with DLB.

« Back to 2024 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/prediction-of-amyloid-positivity-in-dementia-with-lewy-bodies-using-the-early-phase-18f-fp-cit-pet-images/