title: Patient-specific 3D FLAIR for enhanced visualization of brain white matter lesions in multiple sclerosis.
abstract: To improve the conspicuity of white matter lesions (WMLs) in multiple sclerosis (MS) using patient-specific optimization of single-slab 3D fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI).
  
  
  
  Sixteen MS patients were enrolled in a prospective 3.0T MRI study. FLAIR inversion time and echo time were automatically optimized for each patient during the same scan session based on measurements of the relative proton density and relaxation times of the brain tissues. The optimization criterion was to maximize the contrast between gray matter (GM) and white matter (WM), while suppressing cerebrospinal fluid. This criterion also helps increase the contrast between WMLs and WM. The performance of the patient-specific 3D FLAIR protocol relative to the fixed-parameter protocol was assessed both qualitatively and quantitatively.
  
  
  
  Patient-specific optimization achieved a statistically significant 41% increase in the GM-WM contrast ratio (P < 0.05) and 32% increase in the WML-WM contrast ratio (P < 0.01) compared with fixed-parameter FLAIR. The increase in WML-WM contrast ratio correlated strongly with echo time (P < 10-11). Two experienced neuroradiologists indicated substantially higher lesion conspicuity on the patient-specific FLAIR images over conventional FLAIR in 3-4 cases (intrarater correlation coefficient ICC = 0.72). In no case was the image quality of patient-specific FLAIR considered inferior to conventional FLAIR by any of the raters (ICC = 0.32).
  
  
  
  Changes in proton density and relaxation times render fixed-parameter FLAIR suboptimal in terms of lesion contrast. Patient-specific optimization of 3D FLAIR increases lesion conspicuity without scan time penalty, and has potential to enhance the detection of subtle and small lesions in MS.
  
  
  
  1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:557-564.
authors.affiliation: Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Refaat E
authors.initials: RE
authors.lastname: Gabr
authors.affiliation: Philips Healthcare, Cleveland, Ohio, USA.
authors.forename: Amol S
authors.initials: AS
authors.lastname: Pednekar
authors.affiliation: Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Koushik A
authors.initials: KA
authors.lastname: Govindarajan
authors.affiliation: Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Roy F
authors.initials: RF
authors.lastname: Riascos
authors.affiliation: Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: María G
authors.initials: MG
authors.lastname: Ramírez
authors.affiliation: Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Khader M
authors.initials: KM
authors.lastname: Hasan
authors.affiliation: Department of Neurology, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Lincoln
authors.affiliation: Department of Neurology, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Flavia
authors.initials: F
authors.lastname: Nelson
authors.affiliation: Department of Neurology, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Jerry S
authors.initials: JS
authors.lastname: Wolinsky
authors.affiliation: Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA.
authors.forename: Ponnada A
authors.initials: PA
authors.lastname: Narayana
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D002555:Cerebrospinal Fluid; D003287:Contrast Media / Q000737:chemistry; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D015203:Reproducibility of Results; D066127:White Matter / Q000000981:diagnostic imaging*
chemical_list: D003287:Contrast Media
keywords: image analysis; lesion contrast; personalized imaging; precision MRI; real-time; relaxation times