Abstract
BACKGROUND AND PURPOSE: CBR imaging is highly susceptible to a PVE produced by morphologic changes in the brain related to aging and brain laterality. We assessed the influence of PVE produced by regional age-related changes in gray matter volume on I-123 iomazenil SPECT and elucidated the age-related changes in human CBR binding by using PVE-corrected SPECT images.
MATERIALS AND METHODS: Nineteen right-handed healthy volunteers (range, 25–82 years; mean, 55 ± 21 years) underwent MR imaging and quantitative I-123 iomazenil SPECT imaging. The influence of age-related changes in rGMC on SPECT images before PVE correction was assessed. PVE correction of the SPECT images was performed by using an MR imaging–based method. Voxel-based linear regression analyses of the PVE-corrected SPECT images were performed by using SPM5.
RESULTS: The age-related reductions in rGMC and BP without PVE correction revealed a significant direct proportional correlation. Voxel-based statistical analysis with PVE correction showed no significant age-related changes in BP.
CONCLUSIONS: PVE correction was indispensable for the analysis of I-123 iomazenil SPECT images. PVE-corrected quantitative I-123 iomazenil SPECT images revealed no age-related changes in CBR binding in right-handed healthy humans.
Abbreviations
- AAL
- automated anatomic labeling
- BP
- binding potential
- CBR
- central benzodiazepine receptor
- FWHM
- full width at half maximum
- I-123
- iodine 123
- PSF
- point-spreading function
- PVE
- partial volume effect
- rGMC
- regional gray matter concentration
- SPM
- statistical parametric mapping
- VBM
- voxel-based morphometry
- © 2012 American Society of Neuroradiology
Indicates open access to non-subscribers at www.ajnr.org