Q Amyloid: an open platform for quantitative Aβ PET imaging

Brain amyloid-beta (Aβ) deposition is an early neuropathological hallmark of Alzheimer’s Disease (AD), detectable in vivo using PET with radiotracers such as [ 11 C]PiB (PiB), [ 18 F]Florbetaben (FBB), [ 18 F]Florbetapir (FBP), and [ 18 F]Flutemetamol (FTM). As Aβ-targeting therapies advance, accurate, replicable and scalable methods for localising and quantifying brain amyloid burden are becoming crucial. In response to this need, we present Q Amyloid, an open-access platform for the automated quantification of brain Aβ burden. Q Amyloid is based on the Centiloid (CL) framework. Consistently with official guidelines from the Global Alzheimer’s Association Interactive Network (GAAIN), Q Amyloid’s CL scale was defined on PiB data ( subjects) and calibrated for FBB ( subjects), FBP ( subjects), and FTM ( subjects). We performed a large-scale external validation on 7,230 subjects from six public datasets to evaluate Q Amyloid’s performance in differentiating Aβ-negative and Aβ-positive subjects. Q Amyloid’s CL scale met GAAIN criteria for PiB data ( , slope , intercept ). The calibration for 18 F-radiotracers demonstrated similar performances ( ). During external validation, all subjects were successfully analysed, showing good-to-excellent amyloid classification consistency with reference values ( Cohen's κ : ; accuracy: ; overall specificity: ; overall sensitivity: ). Q Amyloid provides a standardised, cloud-based solution for Aβ quantification across multiple radiotracers, enabling automatic quantification of any Aβ-PET scans acquired with GAAIN-compliant protocols. Its open-access nature ensures methodological consistency and reproducibility across studies and centres, supporting early AD diagnosis, the development of Aβ-targeting therapies, and large-scale clinical data analysis. • Q Amyloid addresses the growing need for standardised benchmarks in brain amyloid quantification. • •It implements the Centiloid scale calibrated for [ 11 C]PiB, [ 18 F]Florbetaben, [ 18 F]Florbetapir, and [ 18 F]Flutemetamol scans acquired with EMA-compliant protocols. • •Q Amyloid is validated on a large dataset of 7,230 subjects across six independent cohorts. • •The platform delivers a scalable, transparent tool to democratise amyloid quantification.