Contributions
Abstract: P504
Type: Poster Sessions
Abstract Category: Pathology and pathogenesis of MS - MRI and PET
Background: While white-matter (WM) lesions have been well-characterized in multiple sclerosis, cortical grey-matter (GM) lesions remain largely unexplored because they are usually non-conspicuous on conventional MRI (FLAIR). The aim of our study is to use double-inversion recovery (DIR) MRI to better identify MS lesions in cortical GM, determine their prevalence, and characterize their contrast-enhancement and diffusion. Comparisons were made with WM lesions and correlated with atrophy.
Methods: Relapsing remitting multiple sclerosis (RRMS) patients (N=44) with DIR data were identified. 3T MRI pre- and post-contrast, fluid-attenuated inversion recovery (FLAIR), diffusion weighted imaging (DWI) and DIR were acquired. Lesion segmentation was based on DIR into cortical GM, subcortical WM and periventricular WM, and whether they were enhancing and not, and hyper- or hypo-intense on apparent diffusion coefficient (ADC).
Results: Most (86%) RRMS patients had cortical GM lesions. Compared to WM lesions, GM lesions were fewer in count (328 versus 1604) and volume (32,831 versus 511,125). Of the 328 GM lesions, 97% were not enhanced of which 89% had high ADC. Of the 1095 subcortical WM lesions, 98% were not enhanced, of which only 40% had high ADC. Of the 509 periventricular lesions, 97% were not enhanced, of which 82% showed high ADC. These findings indicate that GM and WM have similar prevalence of enhancement. GM lesions showed similar susceptibility to cytotoxicity as periventricular WM lesions but differed from subcortical WM lesions.
GM lesion count was correlated with GM atrophy (p=0.004) and total brain atrophy (p=0.005), but not with WM atrophy. GM lesion-volume correlated with GM, WM and total brain atrophy (p=0.01, 0.04, 0.006, respectively).
Conclusion: This study identified the prevalence of GM lesions based on DIR, described diffusion changes and contrast-enhancement and compared them with WM lesions. GM and WM had similar percentage of contrast-enhanced lesions. Most enhanced lesions showed higher ADC, suggesting more oedema and/or atrophy. GM lesion count and GM lesion volume, correlated with total brain, WM and GM atrophy. Improved understanding of grey-matter multiple sclerosis pathology is important because it could be better correlated with cognitive and physical disability.
Disclosure: M. Andrea Parra: nothing to disclose. Sindhuja Tirumalai Govindarajan: nothing to disclose. Lev Bangiyev: nothing to disclose. Patricia K. Coyle: nothing to disclose. Olga Syritsyna: nothing to disclose.Tim Q. Duong: nothing to disclose
Abstract: P504
Type: Poster Sessions
Abstract Category: Pathology and pathogenesis of MS - MRI and PET
Background: While white-matter (WM) lesions have been well-characterized in multiple sclerosis, cortical grey-matter (GM) lesions remain largely unexplored because they are usually non-conspicuous on conventional MRI (FLAIR). The aim of our study is to use double-inversion recovery (DIR) MRI to better identify MS lesions in cortical GM, determine their prevalence, and characterize their contrast-enhancement and diffusion. Comparisons were made with WM lesions and correlated with atrophy.
Methods: Relapsing remitting multiple sclerosis (RRMS) patients (N=44) with DIR data were identified. 3T MRI pre- and post-contrast, fluid-attenuated inversion recovery (FLAIR), diffusion weighted imaging (DWI) and DIR were acquired. Lesion segmentation was based on DIR into cortical GM, subcortical WM and periventricular WM, and whether they were enhancing and not, and hyper- or hypo-intense on apparent diffusion coefficient (ADC).
Results: Most (86%) RRMS patients had cortical GM lesions. Compared to WM lesions, GM lesions were fewer in count (328 versus 1604) and volume (32,831 versus 511,125). Of the 328 GM lesions, 97% were not enhanced of which 89% had high ADC. Of the 1095 subcortical WM lesions, 98% were not enhanced, of which only 40% had high ADC. Of the 509 periventricular lesions, 97% were not enhanced, of which 82% showed high ADC. These findings indicate that GM and WM have similar prevalence of enhancement. GM lesions showed similar susceptibility to cytotoxicity as periventricular WM lesions but differed from subcortical WM lesions.
GM lesion count was correlated with GM atrophy (p=0.004) and total brain atrophy (p=0.005), but not with WM atrophy. GM lesion-volume correlated with GM, WM and total brain atrophy (p=0.01, 0.04, 0.006, respectively).
Conclusion: This study identified the prevalence of GM lesions based on DIR, described diffusion changes and contrast-enhancement and compared them with WM lesions. GM and WM had similar percentage of contrast-enhanced lesions. Most enhanced lesions showed higher ADC, suggesting more oedema and/or atrophy. GM lesion count and GM lesion volume, correlated with total brain, WM and GM atrophy. Improved understanding of grey-matter multiple sclerosis pathology is important because it could be better correlated with cognitive and physical disability.
Disclosure: M. Andrea Parra: nothing to disclose. Sindhuja Tirumalai Govindarajan: nothing to disclose. Lev Bangiyev: nothing to disclose. Patricia K. Coyle: nothing to disclose. Olga Syritsyna: nothing to disclose.Tim Q. Duong: nothing to disclose