Here we outline the main findings from two recent FTD center publications. Learn more about our research in easy to digest terms!
Imaging techniques can help distinguish different pathologies in corticobasal syndrome
Adapted from “Multimodal imaging evidence of pathology-mediated disease distribution in corticobasal syndrome”, McMillan et al., 2016
What we know: For individuals with neurodegenerative disease, a confident diagnosis is not available until a postmortem autopsy, when the underlying pathological protein can be revealed. However, neuroimaging can provide clues to the underlying pathology during a patient’s life. Atrophy, or tissue loss caused by cell death, can be detected by structural magnetic resonance imaging (MRI). Different pathologies can cause different patterns of atrophy, and by examining where the brain is atrophied we can guess at the underlying cause. For example, both Alzheimer’s disease (AD) and frontotemporal lobar degeneration (FTLD) are pathologies associated with degeneration of grey matter, the brain cell bodies, but degeneration of white matter, the connection between brain cells, is more severe in FTLD than AD.
What we didn’t know: Corticobasal syndrome (CBS) can occur due to underlying FTLD or AD pathology. In this study, the authors use MRI to detect both grey and white matter atrophy and to distinguish patients with AD pathology from patients without AD pathology.
What this study shows: CBS patients with AD pathology showed greater grey matter atrophy, while CBS patients with non-AD pathology showed greater white matter atrophy. Specifically, CBS patients with AD pathology had less grey matter in the left parietal cortex, the top central part of the brain important for sensory and motor integration. In addition, these patients had degraded white matter connections in the “information highways” of the brain, including the superior longitudinal fasciculus (connecting the front and back of the brain), corpus callosum (connecting the right and left lobes of the brain), and corticospinal tracts (connecting the brain and spinal cord).
What we can do in the future because of this study: The results of this study allow us to use noninvasive MRI techniques in order to predict what pathology is responsible for a patient’s CBS diagnosis during his or her lifetime. However, most of the patient’s pathologies were inferred based on levels of proteins in the cerebrospinal fluid, and only 5 CBS patients were autopsy-confirmed. Future studies using data from our Brain Bank program can help to further confirm the findings reported here.
Why should you care? By knowing the pathology underlying disease, clinicians can better anticipate an individual’s disease course and work to develop targeted treatment strategies.
The influence of education and occupation on disease course in frontotemporal dementia
Adapted from “Cognitive reserve in frontotemporal degeneration: neuroanatomic and neuropsychological evidence”, Placek et al., 2016
What we did know: Theories of cognitive reserve suggest that lifestyle factors such as education and occupation influence an individual’s ability to withstand neurodegenerative disease. A recent study by Dr. Lauren Massimo at the FTDC shows that in patients with FTD, more demanding occupations are associated with a longer survival period.
What we didn’t know: While occupation may prolong survival with FTD, we do not yet know how lifestyle factors influence cognitive performance and brain integrity of FTLD patients during life.
What this study shows: Placek and colleagues studied structural brain images of 55 patients with FTLD, and found that patients with higher education and occupation had greater grey matter density (GMD) in right frontal brain regions. GMD is a quantitative measure of brain cell integrity and greater density indicates less cell loss. Furthermore, greater grey matter in right frontal brain regions was related to superior performance on a higher-level cognitive skill referred to as executive functioning. Importantly, executive functioning is essential for everyday cognitive tasks such as reasoning, decision-making, and planning, which decline during the disease course of FTLD.
What we can do in the future because of this study: This research suggests that the assessment of an individual’s education and occupation may help determine FTLD disease prognosis in regards to cognitive functioning and brain integrity.
Why should you care? This study indicates that individuals with higher education and occupation have less severe cognitive and brain changes associated with FTLD. Understanding how these and other lifestyle factors may contribute to differences in FTLD disease course is important for patient prognosis and caregiver planning.