|Title||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.|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Authors||Zhang Y, Gauthier SA, Gupta A, Chen W, Comunale J, Chiang GC-Y, Zhou D, Askin G, Zhu W, Pitt D, Wang Y|
|Journal||AJNR Am J Neuroradiol|
|Date Published||2016 Sep|
|Keywords||Adult, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Multiple Sclerosis, Myelin Sheath, White Matter|
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.
|Alternate Journal||AJNR Am J Neuroradiol|
|PubMed Central ID||PMC5018433|
|Grant List||R01 EB013443 / EB / NIBIB NIH HHS / United States |
R01 NS090464 / NS / NINDS NIH HHS / United States