Kim SE, Lee B, Park S, et al. - Via involving 310 patients (125 cognitively unimpaired, 125 mild cognitive impairment, and 60 Alzheimer disease dementia) from nine referral centers, researchers sought to investigate the clinical significance of focal Aß deposition in terms of cognition as well as Aß and tau cerebrospinal fluid (CSF) levels. Through visual assessment, they further assessed the order of Aß accumulation. All participants had neuropsychological tests and ¹⁸F-flutemetamol (FMM) PET. According to results, focal Aß deposition was found to have unique clinical features that differ from those of patients with no or diffuse Aß deposition and should be considered as an intermediate stage between no Aß and diffuse Aß deposition. In addition, those who have Aß to a greater extent and striatal involvement exhibit clinical features close to diffuse Aß deposition among patients with focal Aß deposition. In order to assess the progression of disease in patients with focal Aß deposition, more longitudinal studies are required.