Aims: The purpose of the study was to evaluate the reliability of our new visual scale for a
quick atrophy assessment of parietal lobes on brain Magnetic Resonance Imaging (MRI) among
different professionals. A good agreement would justify its use for differential diagnosis of
neurodegenerative dementias, especially early-onset Alzheimer’s Disease (AD), in clinical settings.
Methods: The visual scale named the Parietal Atrophy Score (PAS) is based on a semi-quantitative
assessment ranging from 0 (no atrophy) to 2 (prominent atrophy) in three parietal structures (sulcus
cingularis posterior, precuneus, parietal gyri) on T1-weighted MRI coronal slices through the whole
parietal lobes. We used kappa statistics to evaluate intra-rater and inter-rater agreement among four
raters who independently scored parietal atrophy using PAS. Rater 1 was a neuroanatomist (JM), rater 2
was an expert in MRI acquisition and analysis (II), rater 3 was a medical student (OP) and rater 4 was a
neurologist (DS) who evaluated parietal atrophy twice in a 3-month interval to assess intra-rater
agreement. All raters evaluated the same 50 parietal lobes on brain MRI of 25 cognitively normal
individuals with even distribution across all atrophy degrees from none to prominent according to the
Results: Intra-rater agreement was almost perfect with the kappa value of 0.90. Inter-rater agreement
was moderate to substantial with kappa values ranging from 0.43-0.86.
Conclusion: The Parietal Atrophy Score is the reliable visual scale among raters of different professions
for a quick evaluation of parietal lobes on brain MRI within 1-2 minutes. We believe it could be used as
an adjunct measure in differential diagnosis of dementias, especially early-onset AD.