RT Journal Article
SR Electronic
T1 Quantitative Susceptibility Mapping and R2* Measured Changes during White Matter Lesion Development in Multiple Sclerosis: Myelin Breakdown, Myelin Debris Degradation and Removal, and Iron Accumulation
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1629
OP 1635
DO 10.3174/ajnr.A4825
VO 37
IS 9
A1 Y. Zhang
A1 S.A. Gauthier
A1 A. Gupta
A1 W. Chen
A1 J. Comunale
A1 G.C.-Y. Chiang
A1 D. Zhou
A1 G. Askin
A1 W. Zhu
A1 D. Pitt
A1 Y. Wang
YR 2016
UL http://www.ajnr.org/content/37/9/1629.abstract
AB BACKGROUND AND PURPOSE: Quantitative susceptibility mapping and R2* are sensitive to myelin and iron changes in multiple sclerosis lesions. This study was designed to characterize lesion changes on quantitative susceptibility mapping and R2* at various gadolinium-enhancement stages.MATERIALS AND METHODS: This study included 64 patients with MS with different enhancing patterns in white matter lesions: nodular, shell-like, nonenhancing < 1 year old, and nonenhancing 1–3 years old. These represent acute, late acute, early chronic, and late chronic lesions, respectively. Susceptibility values measured on quantitative susceptibility mapping and R2* values were compared among the 4 lesion types. Their differences were assessed with a generalized estimating equation, controlling for Expanded Disability Status Scale score, age, and disease duration.RESULTS: We analyzed 203 lesions: 80 were nodular-enhancing, of which 77 (96.2%) were isointense on quantitative susceptibility mapping; 33 were shell-enhancing, of which 30 (90.9%) were hyperintense on quantitative susceptibility mapping; and 49 were nonenhancing lesions < 1 year old and 41 were nonenhancing lesions 1–3 years old, all of which were hyperintense on quantitative susceptibility mapping. Their relative susceptibility/R2* values were 0.5 ± 4.4 parts per billion/−5.6 ± 2.9 Hz, 10.2 ± 5.4 parts per billion/−8.0 ± 2.6 Hz, 20.2 ± 7.8 parts per billion/−3.1 ± 2.3 Hz, and 33.2 ± 8.2 parts per billion/−2.0 ± 2.6 Hz, respectively, and were significantly different (P < .005).CONCLUSIONS: Early active MS lesions with nodular enhancement show R2* decrease but no quantitative susceptibility mapping change, reflecting myelin breakdown; late active lesions with peripheral enhancement show R2* decrease and quantitative susceptibility mapping increase in the lesion center, reflecting further degradation and removal of myelin debris; and early or late chronic nonenhancing lesions show both quantitative susceptibility mapping and R2* increase, reflecting iron accumulation.GdgadoliniumGREgradient-echoQSMquantitative susceptibility mapping