Fully Automated Atlas-Based Hippocampal Volumetry for Detection of Alzheimer's Disease in a Memory Clinic Setting

Abstract

Hippocampal volume is a promising biomarker to enhance the accuracy of the diagnosis of dementia due to Alzheimer's disease (AD). However, whereas hippocampal volume is well studied in patient samples from clinical trials, its value in clinical routine patient care is still rather unclear. The aim of the present study, therefore, was to evaluate fully automated atlas-based hippocampal volumetry for detection of AD in the setting of a secondary care expert memory clinic for outpatients. One-hundred consecutive patients with memory complaints were clinically evaluated and categorized into three diagnostic groups: AD, intermediate AD, and non-AD. A software tool based on open source software (Statistical Parametric Mapping SPM8) was employed for fully automated tissue segmentation and stereotactical normalization of high-resolution three-dimensional T1-weighted magnetic resonance images. Predefined standard masks were used for computation of grey matter volume of the left and right hippocampus which then was scaled to the patient's total grey matter volume. The right hippocampal volume provided an area under the receiver operating characteristic curve of 84% for detection of AD patients in the whole sample. This indicates that fully automated MR-based hippocampal volumetry fulfills the requirements for a relevant core feasible biomarker for detection of AD in everyday patient care in a secondary care memory clinic for outpatients. The software used in the present study has been made freely available as an SPM8 toolbox. It is robust and fast so that it is easily integrated into routine workflow.

Structural imaging of hippocampal subfields in healthy aging and Alzheimer’s disease

“…Brewer et al, 2009;Chupin et al, 2009;Fischl et al, 2002;Leung et al, 2010;Morra et al, 2008;Patenaude et al, 2011), enabling less time-consuming and more reproducible segmentations of the structure. From this perspective, major efforts have been made to provide fully automated methods that could be used in clinical routine (Suppa et al, 2015a(Suppa et al, , 2015b.…”

The anteroposterior and primary-to-posterior limbic ratios as MRI-derived volumetric markers of Alzheimer's disease

“…Many authors, using manual methods, automated methods or visual scales, have shown a significant reduction of the volumes of the hippocampus and the entorhinal cortex in both AD and MCI patients [28–56]. The atrophy of the hippocampus has been directly related to neuronal loss, and thus can be considered a marker of neurodegeneration [57].…”

“…High-resolution MRI studies have shown significant differences in the pattern of hippocampal atrophy in patients with AD compared to normal controls, opening the door to new-generation methods based on the hippocampal subfields [58] or the hippocampal shape [59]. In a previous work, Suppa et al described a scaling method quite similar to ours, and also based on taking a gray matter volume as reference [56]. In particular, they used a set of standard masks for the computation of the gray matter volumes of the left and right hippocampus, which then were scaled to the patient's total gray matter volume.…”

Structural Image Analysis of the Brain in Neuropsychology Using Magnetic Resonance Imaging (MRI) Techniques

“…The examples shown thus far for automated image analyses have been mainly discussed in terms of whole brain analyses, but analyses may also be directed to a specific region, when for example there is an a priori hypothesis for a particular ROI, like the basal ganglia, cerebellum or hippocampus (Glatz et al 2015;Suppa et al 2015;Wu et al 2012). In such circumstances a Bmask^is placed over the ROI, so that comparisons are focused just within the ROI, reducing some of the restrictiveness of family wise error.…”