title: Magnetic Susceptibility from Quantitative Susceptibility Mapping Can Differentiate New Enhancing from Nonenhancing Multiple Sclerosis Lesions without Gadolinium Injection.
abstract: OBJECTIVE
  Magnetic susceptibility values of multiple sclerosis lesions increase as they change from gadolinium-enhancing to nonenhancing. Can susceptibility values measured on quantitative susceptibility mapping without gadolinium injection be used to identify the status of lesion enhancement in surveillance MR imaging used to monitor patients with MS?
  
  
  METHODS
  In patients who had prior MR imaging and quantitative susceptibility mapping in a current MR imaging, new T2-weighted lesions were evaluated for enhancement on conventional T1-weighted imaging with gadolinium, and their susceptibility values were measured on quantitative susceptibility mapping. Receiver operating characteristic analysis was used to assess the diagnostic accuracy of using quantitative susceptibility mapping in distinguishing new gadolinium-enhancing from new nonenhancing lesions. A generalized estimating equation was used to assess differences in susceptibility values among lesion types.
  
  
  RESULTS
  In 54 patients, we identified 86 of 133 new lesions that were gadolinium-enhancing and had relative susceptibility values significantly lower than those of nonenhancing lesions (β = -17.2; 95% CI, -20.2 to -14.2;P< .0001). Using susceptibility values to discriminate enhancing from nonenhancing lesions, we performed receiver operating characteristic analysis and found that the area under the curve was 0.95 (95% CI, 0.92-0.99). Sensitivity was measured at 88.4%, and specificity, at 91.5%, with a cutoff value of 11.2 parts per billion for quantitative susceptibility mapping-measured susceptibility.
  
  
  CONCLUSIONS
  During routine MR imaging monitoring to detect new MS lesion activity, quantitative susceptibility mapping can be used without gadolinium injection for accurate identification of the BBB leakage status in new T2WI lesions.
authors.affiliation: From the Department of Radiology (Y.Z., W.C., W.Z.), Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.|Department of Radiology (Y.Z., C.A.S., Y.W.), Weill Cornell Medical College, New York, New York.
authors.forename: Y
authors.identifier: http://orcid.org/0000-0002-2251-3777
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Departments of Neurology (S.A.G.).
authors.forename: S A
authors.identifier: http://orcid.org/0000-0002-4015-1781
authors.initials: SA
authors.lastname: Gauthier
authors.affiliation: Radiology (A.G., J.C., G.C.-Y.C.), Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York.
authors.forename: A
authors.identifier: http://orcid.org/0000-0003-2816-0340
authors.initials: A
authors.lastname: Gupta
authors.affiliation: School of Applied and Engineering Physics (L.T.).
authors.forename: L
authors.identifier: http://orcid.org/0000-0002-0969-9300
authors.initials: L
authors.lastname: Tu
authors.affiliation: Radiology (A.G., J.C., G.C.-Y.C.), Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York.
authors.forename: J
authors.identifier: http://orcid.org/0000-0001-6063-0109
authors.initials: J
authors.lastname: Comunale
authors.affiliation: Radiology (A.G., J.C., G.C.-Y.C.), Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York.
authors.forename: G C-Y
authors.identifier: http://orcid.org/0000-0001-9925-0816
authors.initials: GC
authors.lastname: Chiang
authors.affiliation: From the Department of Radiology (Y.Z., W.C., W.Z.), Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: W
authors.identifier: http://orcid.org/0000-0001-8014-2364
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Radiology (Y.Z., C.A.S., Y.W.), Weill Cornell Medical College, New York, New York.|Department of Biomedical Engineering (Y.W.), Cornell University, Ithaca, New York.
authors.forename: C A
authors.identifier: http://orcid.org/0000-0001-9580-8499
authors.initials: CA
authors.lastname: Salustri
authors.affiliation: From the Department of Radiology (Y.Z., W.C., W.Z.), Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: W
authors.identifier: http://orcid.org/0000-0002-0254-6563
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Department of Radiology (Y.Z., C.A.S., Y.W.), Weill Cornell Medical College, New York, New York yiwang@med.cornell.edu.|Department of Biomedical Engineering (Y.W.), Cornell University, Ithaca, New York.
authors.forename: Y
authors.identifier: http://orcid.org/0000-0003-1404-8526
authors.initials: Y
authors.lastname: Wang