Vol.:(0123456789) 1 3 Annals of Nuclear Medicine https://doi.org/10.1007/s12149-020-01453-y ORIGINAL ARTICLE Relationships between amyloid levels, glucose metabolism, morphologic changes in the brain and clinical status of patients with Alzheimer’s disease Tanyaluck Thientunyakit 1  · Chakmeedaj Sethanandha 1  · Weerasak Muangpaisan 2  · Orasa Chawalparit 1  · Kuntarat Arunrungvichian 3  · Tossaporn Siriprapa 1  · Yudthaphon Vichianin 4  · Swatabdi Kamal 5  · Chaiyawat Suppasilp 1  · Thonnapong Thongpraparn 1  · Rujaporn Chanachai 1  · Juri G. Gelovani 1,5 Received: 10 November 2019 / Accepted: 22 February 2020 © The Japanese Society of Nuclear Medicine 2020 Abstract Objective The current study was conducted to improve the understanding of relationships between regional cortical amyloid load, glucose metabolism, cortical morphology (volume), and severity of clinical symptoms in patients with AD, MCI, and age-matched controls. Methods To objectivize the radiological evaluation of patients with suspected AD, head-to-head multi-modality imaging studies were conducted using MRI and PET/CT with [ 18 F]FDG and [ 18 F]AV45 for visualization and quantitation of brain morphology, glucose metabolism, and amyloid levels, respectively. A total of 84 subjects was studied, including 33 patients with AD, 31 patients with MCI, and 20 age-matched healthy controls (HC). A new quantitative index was calculated as a ratio of regional SUV of [ 18 F]AV45 (normalized to cerebellar cortex) over the corresponding regional SUV of [ 18 F]FDG, divided by the corresponding regional volume, measured from the co-registered MRI and normalized to the normal age- matched control group (AV45/FDG/NVol index). Relationships between clinical scores (TMSE, ADAS) and AV45/FDG/ NVol indices for diferent structures of the brain in study groups were determined using linear regression analyses. Results A signifcant direct linear correlation was observed between the AV45/FDG/NVol index and ADAS-Cog test score and an inverse correlation with TMSE score at baseline and with the degree of changes in ADAS and TMSE scores assessed one year later (disease progression). The observed correlations between AV45/FDG/NVol index and clinical scores were higher than those with MRI-based cortical volumes, FDG SUV, or cerebellum-normalized AV45 SUV alone. Conclusions Current study demonstrated that AV45/FDG/NVol index mapping of the brain is a novel quantitative molecular imaging biomarker that correlates with clinical neurocognitive status and may facilitate more accurate diagnosis, staging, and prognosis of AD. Additional larger scale clinical studies are required to further evaluate the efcacy of this new quantitative index as a diagnostic and prognostic biomarker of AD as well as for the evaluation of safety and efcacy of novel agents undergoing clinical trials for therapy of AD. Keywords Alzheimer’s disease · Mild cognitive impairment · MRI · FDG · AV45 · Amyloid Electronic supplementary material The online version of this article (https://doi.org/10.1007/s12149-020-01453-y) contains supplementary material, which is available to authorized users. * Tanyaluck Thientunyakit stanyalu@hotmail.com 1 Department of Radiology, Her Majesty’s Cardiac Center, Division of Nuclear Medicine, Faculty of Medicine, Siriraj Hospital, Building Fl.12th, 2 Wanglang Road Bangkoknoi, Bangkok 10700, Thailand 2 Department of Preventive and Social Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand 3 Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand 4 Department of Radiological Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand 5 Departments of Neurosurgery, Oncology, OBGYN, Biomedical Engineering, School of Medicine, College of Engineering, and Karmanos Cancer Institute, Wayne State University, Detroit, MI, USA