Alzheimer’s Disease: Preserved Brain Volume & MRI Outcomes

Researchers are increasingly utilizing magnetic resonance imaging (MRI) to aid in the diagnosis of Alzheimer’s disease, moving beyond its initial role in excluding other potential causes of dementia. While historically used to rule out conditions like subdural hematomas, intracranial tumors, and normal pressure hydrocephalus, MRI is now capable of identifying specific patterns associated with neurodegenerative diseases, including Alzheimer’s.

A key focus of MRI analysis is the assessment of volume change in the brain, particularly in the medial temporal lobe. According to Radiopaedia.org, MRI and computed tomography (CT) scans are used to assess these changes. The Radiology Assistant notes that a high medial temporal lobe atrophy (MTA) score is highly sensitive for diagnosing Alzheimer’s disease and is present in the majority of patients with the condition.

Early diagnosis is a critical area of focus, with researchers seeking to identify prodromal stages like Mild Cognitive Impairment (MCI). Early detection allows for timely intervention with current and potential future therapeutic strategies. MRI also plays a role in monitoring disease progression and is utilized in clinical trials focused on MCI and Alzheimer’s.

Beyond assessing the medial temporal lobe, MRI can also reveal parietal lobe atrophy, particularly in the posterior regions, which is indicative of Alzheimer’s. In other forms of dementia, such as vascular dementia, MRI can identify generalized cerebral atrophy, confluent white matter hyperintensities, lacunar infarcts, and strategic infarcts. Still, in Dementia with Lewy Bodies, MRI often does not reveal specific abnormalities.

Recent advancements, detailed in a study published by Nature in September 2025, demonstrate the potential of advanced MRI techniques to improve Alzheimer’s diagnosis through ensemble methods. These methods leverage the ability of MRI to detect brain atrophy in the hippocampus, a key indicator of the disease.

The role of neuroimaging in dementia assessment has evolved significantly, according to The Radiology Assistant, and is no longer limited to simply excluding structural lesions. Systematic evaluation of MRI studies involves excluding treatable conditions, assessing for global and focal atrophy, and evaluating for vascular disease.