Figure 1. Cerebrospinal Fluid (CSF) Alzheimer Disease (AD) Biomarkers and Flutemetamol F 18–Labeled Positron Emission Tomography (PET).

A, Concordance between visual and quantitative amyloid PET analysis. Composite standardized uptake value ratio (SUVR) of [¹⁸F]flutemetamol data in patients who were classified as negative (n = 149) or positive (n = 113) for amyloid findings with visual PET assessment are shown. The dotted line represents a cutoff of greater than 1.42 SUVR. Data points indicate individuals. B-F, Correlation of CSF AD biomarkers with [¹⁸F]flutemetamol PET status according to visual analysis. Levels of CSF β-amyloid (Aβ) 42 were analyzed with the classic INNOTEST (INC), modified INNOTEST (INM), EUROIMMUN (EI) and Meso Scale Discovery (MSD) assays. To calculate the CSF Aβ42:Aβ40 ratio, we used Aβ40 kits from the assay vendors Fujirebio (INC and INM), EUROIMMUN (EI), and Meso Scale Discovery (MSD). Levels of CSF total tau (T-tau) and phosphorylated tau (P-tau) were measured with the EI and INNOTEST assays, respectively. Receiver operating characteristic (ROC) curves were generated for Aβ42 level (B-F), the Aβ42:Aβ40 ratio (C [INC] and D [INM, EI, and MSD]), the Aβ42:T-tau ratio (C [INC] and E [INM, EI, and MSD]), and the Aβ42:P-tau ratio (C [INC] and F [INM, EI, and MSD]) to determine their accuracy in differentiating Aβ-negative (n = 149) and Aβ-positive (n = 113) visual readings. AUC indicates area under the ROC curve.