Abstract
ObjectiveTo determine whether reliable brain atrophy measures can be obtained from post-contrast 3D T1-weighted images in patients with multiple sclerosis (MS) using FreeSurfer.MethodsTwenty-two patients with MS were included, in which 3D T1-weighted MR images were obtained during the same scanner visit, with the same acquisition protocol, before and after administration of gadolinium-based contrast agents (GBCAs). Two FreeSurfer versions (v.6.0.1 and v.7.1.1.) were applied to calculate grey matter (GM) and white matter (WM) volumes and global and regional cortical thickness. The consistency between measures obtained in pre- and post-contrast images was assessed by intra-class correlation coefficient (ICC), the difference was investigated by paired t-tests, and the mean percentage increase or decrease was calculated for total WM and GM matter volume, total deep GM and thalamus volume, and mean cortical thickness.ResultsGood to excellent reliability was found between all investigated measures, with ICC ranging from 0.926 to 0.996, all p values < 0.001. GM volumes and cortical thickness measurements were significantly higher in post-contrast images by 3.1 to 17.4%, while total WM volume decreased significantly by 1.7% (all p values < 0.001).ConclusionThe consistency between values obtained from pre- and post-contrast images was excellent, suggesting it may be possible to extract reliable brain atrophy measurements from T1-weighted images acquired after administration of GBCAs, using FreeSurfer. However, absolute values were systematically different between pre- and post-contrast images, meaning that such images should not be compared directly. Potential systematic effects, possibly dependent on GBCA dose or the delay time after contrast injection, should be investigated.Trial registrationClinical trials.gov. identifier: NCT00360906.Key Points• The influence of gadolinium-based contrast agents (GBCAs) on atrophy measurements is still largely unknown and challenges the use of a considerable source of historical and prospective real-world data.• In 22 patients with multiple sclerosis, the consistency between brain atrophy measurements obtained from pre- and post-contrast images was excellent, suggesting it may be possible to extract reliable atrophy measurements in T1-weighted images acquired after administration of GBCAs, using FreeSurfer.• Absolute values were systematically different between pre- and post-contrast images, meaning that such images should not be compared directly, and measurements extracted from certain regions (e.g., the temporal pole) should be interpreted with caution.
Highlights
Grey matter (GM) atrophy measured on MRI in persons with multiple sclerosis (MS) reflects irreversible neuroaxonal loss and neurodegenerative changes in the CNS [1]
Absolute values were systematically different between pre- and post-contrast images, meaning that such images should not be compared directly, and measurements extracted from certain regions should be interpreted with caution
This is in agreement with previous studies investigating the whole brain [36], upper cervical cord area [37], and GM and white matter (WM) measurements [23] using SIENAX [23, 36], volBrain, and FMRIB Software Library (FSL)-Anat [23] and may imply that reliable atrophy measurements acquired from post-contrast images are possible across segmentation techniques
Summary
Grey matter (GM) atrophy measured on MRI in persons with multiple sclerosis (MS) reflects irreversible neuroaxonal loss and neurodegenerative changes in the CNS [1]. The degree of GM atrophy has been shown to consistently correlate with physical [2, 3] and cognitive [4] disability, and is regarded as a promising neurodegenerative biomarker. There are a number of available methods and software to measure GM atrophy. FreeSurfer is publicly available and widely validated [8,9,10,11,12], and in the body of literature on GM atrophy in MS, many key papers have used FreeSurfer [13,14,15]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
