Regional white matter decreases in Alzheimer's disease using optimized voxel-based morphometry
1Department of Bioengineering, Beijing University of Aeronautics and Astronautics, Beijing, China.
Acta Radiologica (Stockholm, Sweden : 1987)
|January 23, 2008
Summary
Alzheimer's disease (AD) patients exhibit reduced white matter volume, particularly in the posterior corpus callosum and temporal lobes. These white matter abnormalities may underlie functional disconnection in AD.
Area of Science:
- Neuroimaging
- Neurology
- Alzheimer's Disease Research
Background:
- Cortical gray matter changes are often studied in Alzheimer's disease (AD).
- White matter fiber abnormalities may also contribute to AD-related functional disconnection.
Purpose of the Study:
- To investigate regional white matter volume changes in AD patients compared to healthy controls.
- To identify specific areas of white matter affected in Alzheimer's disease.
Main Methods:
- Optimized voxel-based morphometry (VBM) applied to whole-brain MRI scans.
- Analysis included 19 AD patients and 20 healthy subjects.
- Manual outlining and normalization of the corpus callosum (CC) in midsagittal slices.
Main Results:
- AD patients showed significantly reduced white matter volume in the posterior CC and temporal lobes (bilateral).
- The peak statistical difference in white matter reduction was observed in the left posterior CC.
- All five subdivisions of the corpus callosum were significantly smaller in AD patients.
Conclusions:
- White matter abnormalities, especially in the posterior CC and temporal lobes, are present in Alzheimer's disease.
- These structural changes in white matter may contribute to the functional disconnections observed in AD.
- Findings highlight the importance of white matter integrity in Alzheimer's disease pathogenesis.
Related Concept Videos
01:23Alzheimer Disease ll: Pathophysiology
Alzheimer disease involves structural changes in the brain that begin long before symptoms appear. The most distinctive features are extracellular neuritic plaques and intracellular neurofibrillary tangles.Neuritic plaques form in the cerebral cortex and around blood vessels. These plaques contain a dense core of beta-amyloid (Aβ)—a toxic protein fragment that clumps outside neurons. The core is surrounded by damaged neuronal extensions, as well as reactive astrocytes and microglia. Abnormal...
01:26Alzheimer's Disease: Overview
Alzheimer's Disease (AD) is a continually advancing neurodegenerative disorder, distinguished by escalating memory loss, cognitive dysfunction, and dementia. The disease unfolds in three stages: preclinical, mild cognitive impairment (MCI), and dementia. Its onset is insidious, and the progression gradual, with the cause not well explained by other disorders.
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ and tau...
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ and tau...
01:29Alzheimer Disease l: Introduction
Alzheimer disease is a chronic, progressive, and irreversible neurodegenerative disorder and the most common cause of dementia in older adults. It leads to gradual neuronal loss, causing cognitive decline, behavioral changes, and loss of functional independence.Risk Factors and EtiologyThe disease is multifactorial. Age is the strongest risk factor, with prevalence doubling every 5 years after age 65. Genetic factors include mutations in genes such as APP, PSEN1, and PSEN2, which are associated...
01:22Alzheimer's Disease: Treatment
Alzheimer's Disease (AD), a neurodegenerative disorder, is pathologically identified by amyloid plaques and neurofibrillary tangles composed of tau protein. AD pharmacotherapy aims to manage cognitive symptoms, delay disease progression, and treat behavioral symptoms. The treatment is primarily symptomatic and palliative, with no definitive disease-modifying therapy available. Cholinesterase inhibitors, including donepezil (Aricept), rivastigmine (Exelon), and galantamine (Razadyne), are...
01:22Dementia l: Introduction
Dementia is an acquired, progressive syndrome characterized by a decline in multiple cognitive domains severe enough to impair daily functioning and reduce independence. Although memory loss is a central feature, the diagnosis requires additional deficits involving language, executive function, visuospatial skills, judgment, calculation, or abstract reasoning. These cognitive impairments reflect underlying neurodegenerative or vascular processes that gradually disrupt neuronal networks...