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Lifespan normative data on rates of brain volume changes
Marco Battaglini1, Giordano Gentile1, Ludovico Luchetti1
1Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy.
Neurobiology of Aging
|June 18, 2019
Summary
This study establishes normative values for yearly brain volume change in healthy adults, revealing age and scanner field strength influence. A new calculator aids in distinguishing normal aging from neurological disease progression.
Area of Science:
- Neuroimaging
- Radiology
- Biostatistics
Background:
- Brain volume change is a key indicator in neurological disorders.
- Quantifying normal brain volume change across the adult lifespan is crucial for clinical assessment.
- Existing methods for measuring brain volume change lack comprehensive normative data.
Purpose of the Study:
- To establish normative values for yearly percentage brain volume change (PBVC/y) in healthy adults.
- To develop a calculator for assessing deviations from expected PBVC/y in neurological conditions.
- To investigate the influence of age, sex, and MRI parameters on PBVC/y.
Main Methods:
- Utilized multicenter MRI data from 720 healthy participants (16-90 years).
- Calculated PBVC/y using Structural Imaging Evaluation, using Normalization, of Atrophy (SIENA) software.
- Employed mixed-effects models to analyze associations between PBVC/y and demographic/imaging variables.
Main Results:
- PBVC/y significantly increases with age, with individuals aged 60-70 showing twice the volume decrease compared to those aged 30-40.
- Higher brain volume decrease was observed with 1.5T scanners compared to 3T scanners.
- Longer interscan intervals reduced the variability of PBVC/y normative percentiles.
Conclusions:
- Normative PBVC/y data and a freely available calculator can aid in differentiating pathological from physiological brain volume changes.
- Age and MRI field strength are critical factors influencing brain volume loss.
- These findings support improved diagnostic accuracy in neurological disorders.
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