2021 CMSC Annual Meeting

Compliance of a Real-World Dataset with the CMSC 2018 Guidelines


Acquiring brain magnetic resonance images (MRI) in a standardized way, following CMSC guidelines, increases image consistency and quality, supporting accurate diagnosis and follow-up of multiple sclerosis (MS) patients.
This study evaluated MRI acquisition parameters in a real-world dataset acquired from MS patients and compared them with the CMSC brain MRI guidelines (2018 revision).
According to the 2018 CMSC brain MRI protocol guidelines, sagittal and axial fluid-attenuated inversion recovery (FLAIR) scans acquired preferably 3D (or 2D if 3D not available) and a 3D inversion-recovery prepared (IR-prep) gradient-echo T1 without contrast should be acquired. For every scan, in-slice pixel resolution ? 1mm x 1mm and slice thickness ? 3mm with no slice gap are required.
The real-world dataset consisted of 140 sessions from 83 patients, acquired with 58 different scanners in the period January 2016 to November 2019. There were 66 T1 non-contrast scans and 128 FLAIR scans.
In the considered data, 45% of the T1 non-contrast scans were 2D acquisitions and therefore did not comply with the CMSC 2018 acquisition guidelines. All 3D T1 scans without contrast complied. Of the 128 FLAIR scans, 56% were 3D acquired. For the remaining 44% FLAIR scans which were acquired 2D, none had both the sagittal and axial acquisitions, with 75% having only an axial and 25% only a sagittal scan. No coronal 2D images were acquired. All 3D acquired FLAIR images fully complied with the guidelines. For the 2D FLAIR acquired scans, only 4% were acquired contiguous without a slice gap and 77% had a slice thickness greater than 3mm, however the in-plane resolution of all images was under 1mmx1mm. When considering all parameters, all 2D FLAIR scans were non-compliant, leading to a total of 44% of all FLAIR scans that did not comply.
In this real-world dataset, only half of the scans acquired (55% 3D T1 and 56% FLAIR) satisfied the 2018 CMSC Standardized Brain MRI recommendations and these were primarily those acquired 3D. While the guidelines allowed for 2D FLAIR acquisitions when 3D acquisition was not available, these 2D acquired scans did not comply with the recommended imaging parameters of slice thickness ? 3mm with no slice gap. A higher compliance with the guidelines would provide more confidence in the use of brain MRI for diagnosis and follow-up of MS patients.