Callosal thickness profiles for prognosticating conversion from mild cognitive impairment to Alzheimer’s disease: A classification approach

Abstract

IntroductionAlzheimer's disease (AD) is the most common form of dementia. Finding biomarkers to prognosticate transition from mild cognitive impairment (MCI) to AD is important to clinical medicine. Promising imaging biomarkers of AD conversion identified so far include atrophy of the cerebral cortex and subcortical gray matter nuclei.MethodsThis study introduces thickness and bending angle of the corpus callosum as a putative white matter marker of MCI to AD conversion. The corpus callosum is computationally less demanding to segment automatically compared to more complicated structures and a subject can be processed in a few minutes. We aimed to demonstrate that callosal shape and thickness measures provide a simple, effective, and accurate prognostication tool in ADNI dataset. Using longitudinal datasets, we classified MCI subjects based on conversion to AD assessed via cognitive testing. We evaluated the classification accuracy of callosal shape features in comparison with the existing “gold standard” cortical thickness and subcortical gray matter volume measures.ResultsThe callosal thickness measures were less accurate in classifying conversion status by cognitive scores compared to gray matter measures for AD.ConclusionsWhile this paper presented a negative result, this method may be more suitable for a disease of the white matter.

Plasma Transthyretin as a Predictor of Amnestic Mild Cognitive Impairment Conversion to Dementia

“…Other studies have also shown that absent APOE4 alleles may predict MCI stability for at least 3 years 36 , plasma homocysteine and serum brain-derived neurotrophic factor may predict MCI-to-AD conversion in patients with the APOE ε4 genotype 37 , and plasma beta-secretase 1 activity is significantly increased in MCI converters 38 . Some neuroimaging approaches have provided other ways to predict MCI-to-AD conversion 39,40 . However, MCI is a diverse group, and the progression from MCI to AD is dynamic.…”