Inversion Recovery Susceptibility Weighted Imaging with Enhanced T2Weighting at 3 T Improves Visualization of Subpial Cortical Multiple Sclerosis Lesions

Erin S. Beck, Neville Gai, Stefano Filippini, Josefina Maranzano, Govind Nair, Daniel S. Reich

Research output: Contribution to journalArticlepeer-review

22 Scopus citations

Abstract

Objectives Cortical demyelination is common in multiple sclerosis (MS) and can be extensive. Cortical lesions contribute to disability independently from white matter lesions and may form via a distinct mechanism. However, current magnetic resonance imaging methods at 3 T are insensitive to cortical, and especially subpial cortical, lesions. Subpial lesions are well seen on T2∗-weighted imaging at 7 T, but T2∗-weighted methods on 3 T scanners are limited by poor lesion-to-cortex and cerebrospinal fluid-to-lesion contrast. We aimed to develop and evaluate a cerebrospinal fluid-suppressed, T2∗-weighted sequence optimized for subpial cortical lesion visualization. Materials and Methods We developed a new magnetic resonance imaging sequence, inversion recovery susceptibility weighted imaging with enhanced T2 weighting (IR-SWIET; 0.8 mm × 0.8 mm in plane, 0.64 mm slice thickness with whole brain coverage, acquisition time 5 minutes). We compared cortical lesion visualization independently on IR-SWIET (median signal from 4 acquisitions), magnetization-prepared 2 rapid acquisition gradient echoes (MP2RAGE), double inversion recovery (DIR), T2∗-weighted segmented echo-planar imaging, and phase-sensitive inversion recovery images for 10 adults with MS. We also identified cortical lesions with a multicontrast reading of IR-SWIET (median of 2 acquisitions), MP2RAGE, and fluid-attenuated inversion recovery (FLAIR) images for each case. Lesions identified on 3 T images were verified on "gold standard"7 T T2∗ and MP2RAGE images. Results Cortical, and particularly subpial, lesions appeared much more conspicuous on IR-SWIET compared with other 3 T methods. A total of 101 true-positive subpial lesions were identified on IR-SWIET (average per-participant sensitivity vs 7 T, 29% ± 8%) versus 36 on MP2RAGE (5% ± 2%; comparison to IR-SWIET sensitivity, P = 0.07), 17 on FLAIR (2% ± 1%; P < 0.05), 28 on DIR (6% ± 2%; P < 0.05), 42 on T2∗-weighted segmented echo-planar imaging (11% ± 5%; P < 0.05), and 13 on phase-sensitive inversion recovery (4% ± 2%; P < 0.05). When a combination of IR-SWIET, MP2RAGE, and FLAIR images was used, a total of 147 subpial lesions (30% ± 5%) were identified versus 83 (16% ± 3%, P < 0.01) on a combination of DIR, MP2RAGE, and FLAIR. More cases had at least 1 subpial lesion on IR-SWIET, and IR-SWIET improved cortical lesion subtyping accuracy and correlation with 7 T subpial lesion number. Conclusions Subpial lesions are better visualized on IR-SWIET compared with other 3 T methods. A 3 T protocol combining IR-SWIET with MP2RAGE, in which leukocortical lesions are well seen, improves cortical lesion visualization over existing approaches. Therefore, IR-SWIET may enable improved MS diagnostic specificity and a better understanding of the clinical implications of cortical demyelination.

Original languageEnglish
Pages (from-to)727-735
Number of pages9
JournalInvestigative Radiology
Volume55
Issue number11
DOIs
StatePublished - 1 Nov 2020
Externally publishedYes

Keywords

  • -weighted magnetic resonance imaging
  • T
  • cortical lesions
  • magnetic susceptibility
  • multiple sclerosis
  • neuroimaging

Fingerprint

Dive into the research topics of 'Inversion Recovery Susceptibility Weighted Imaging with Enhanced T2Weighting at 3 T Improves Visualization of Subpial Cortical Multiple Sclerosis Lesions'. Together they form a unique fingerprint.

Cite this