Identifying Alzheimer’s disease with NeuroQuant

By: Marilyn Maes MS, RA, RT (R), (MR) 

Overview:

Physicians use several evaluation tools to make accurate assessments of memory loss in patients, one of them is a magnetic resonance imaging (MRI) scan of the patient’s brain. A NeuroQuant analysis can be used with the routine MRI brain scan to provide additional insight.  

NeuroQuant, the first FDA 510(k) cleared medical software for quantitative analysis of brain MRI, provides brain structure volumetrics to assist physicians in fast and accurate diagnoses of neurodegenerative diseases. 

When assessing dementia, NeuroQuant uses images from the MRI scan to measure the volume of brain structures relevant in memory loss pathologies. The software allows physicians to identify particular areas of concern, such as the hippocampus, entorhinal cortex, and inferior lateral ventricles. 

NeuroQuant provides reference percentiles for structures using an extensive covariate modulated normative database with ages from 3 – 100 years of age, both genders and ethnicities from around the globe. The structure volumes are compared to healthy subjects of the same age and sex, then normalized by intracranial volume (ICV) to provide a normal percentile between 1 and 99. Structure volumes falling outside of the 5th-95th percentile are typically of diagnostic importance. 

AD is one of the most notorious and the most common forms of dementia, accounting for 60% to 90% of the dementing disorders with progressive memory loss often with personality changes and impaired cognition. 

AD brains demonstrate specific patterns of atrophy predominantly in regions mediating cognitive functions such as the temporal lobes. In most AD pathologies the atrophy distribution follows this pattern, hippocampus initially, with the entorhinal cortex first. Then, hippocampal and amygdala atrophy and global atrophy. Late stages are generally bilateral, symmetric, and diffuse. The disease advancement is from the entorhinal cortex to the hippocampus to the neo-cortex as a rule. 

NeuroQuant was used part of an AD work up on a 79-year-old, female patient and demonstrates an early AD pattern of atrophy. 

Alzheimer’s Disease in NeuroQuant

Results:

Head MRI: Revealed cortical atrophy and periventricular white matter changes. No tumor, hemorrhage, subdural hematoma, or large cerebral infarct.

PET: Neuronal injury (FDG PETQuant, structural MRI)

Neuropsychologic: Confirmed mild dementia, with deficits in memory, language, visuospatial skills, and frontal/executive function.

NeuroQuant: Analysis demonstrates statistically significant hippocampal atrophy in the 1st percentile and statistically significant compensatory inferior lateral ventricle enlargement in the 99th percentile. There is also statistically significant reduction of the HOC in the 1st percentile, and borderline low entorhinal cortex volume in the 6th percentile. Suggestive of early dementia due to Alzheimer’s disease.

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