Translational MRI Volumetry with NeuroQuant: Effects of Version and Normative Data on Relationships with Memory Performance in Healthy Older Adults and Patients with Mild Cognitive Impairment

Article type: Research Article

Authors: Stelmokas, Julija^a | Yassay, Lance^{a; b} | Giordani, Bruno^{b; c; d} | Dodge, Hiroko H.^{d; e} | Dinov, Ivo D.^{f; g; h} | Bhaumik, Arijit^d | Sathian, K.^{i; j} | Hampstead, Benjamin M.^{a; b; *}

Affiliations: [a] Veterans Affairs Ann Arbor Healthcare System, Mental Health Service, Ann Arbor, MI, USA | [b] Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA | [c] Departments of Neurology, and Psychology and School of Nursing, University of Michigan, Ann Arbor, MI,  USA | [d] Michigan Alzheimer’s Disease Core Center, University of Michigan, AnnArbor, MI, USA | [e] Department of Neurology and Layton Aging and Alzheimer’s Disease Center, Oregon Health and Science University, Portland, OR, USA | [f] Statistics Online Computational Resource, School of Nursing, Michigan Institute for Data Science, University of Michigan, Ann Arbor, MI, USA | [g] Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, CA, USA | [h] Udall Center of Excellence for Parkinson’s Disease Research, University of Michigan, Ann Arbor, MI, USA | [i] Departments of Neurology, Rehabilitation Medicine, and Psychology, Emory University, Atlanta, GA, USA | [j] Rehabilitation R&D Center for Visual and Neurocognitive Rehabilitation, Atlanta VAMC, Decatur, GA, USA

Correspondence: [*] Correspondence to: Benjamin M. Hampstead, PhD, 2101 Commonwealth Blvd Suite C, Ann Arbor, MI 48105, USA. Tel.: +1 734 763 9259; Fax: +1 734 936 8262; E-mail: bhampste@med.umich.edu.

Abstract: NeuroQuant (NQ) is a fully-automated program that overcomes several existing limitations in the clinical translation of MRI-derived volumetry. The current study characterized differences between the original (NQ1) and an updated NQ version (NQ2) by 1) replicating previously identified relationships between neuropsychological test performance and medial temporal lobe volumes, 2) evaluating the level of agreement between NQ versions, and 3) determining if the addition of NQ2 age-/sex-based z-scores hold greater clinical utility for prediction of memory impairment than standard percent of intracranial volume (% ICV) values. Sixty-seven healthy older adults and 65 mild cognitive impairment patients underwent structural MRI and completed cognitive testing, including the Immediate and Delayed Memory indices from the Repeatable Battery for the Assessment of Neuropsychological Status. Results generally replicated previous relationships between key medial temporal lobe regions and memory test performance, though comparison of NQ regions revealed statistically different values that were biased toward one version or the other depending on the region. NQ2 hippocampal z-scores explained additional variance in memory performance relative to % ICV values. Findings indicate that NQ1/2 medial temporal lobe volumes, especially age- and sex-based z-scores, hold clinical value, though caution is warranted when directly comparing volumes across NQ versions.

Keywords: Alzheimer’s disease, amygdala, hippocampus, memory, neuroimaging

DOI: 10.3233/JAD-170306

Journal: Journal of Alzheimer's Disease, vol. 60, no. 4, pp. 1499-1510, 2017