title: Reduction of Oxygen-Induced CSF Hyperintensity on FLAIR MR Images in Sedated Children: Usefulness of Magnetization-Prepared FLAIR Imaging.
abstract: Oxygen-induced CSF hyperintensity on FLAIR MR imaging is often observed in sedated children. This phenomenon can mimic leptomeningeal pathology and lead to a misdiagnosis. The purpose of this study was to investigate whether magnetization-prepared FLAIR MR imaging can reduce oxygen-induced CSF hyperintensity and improve image quality compared with conventional (non-magnetization-prepared) FLAIR MR imaging.
  
  
  
  Bloch simulation for magnetization-prepared and non-magnetization-prepared FLAIR sequences was performed for tissue contrast. We retrospectively reviewed 85 children with epilepsy who underwent MR imaging under general anesthesia with supplemental oxygen (41 with non-magnetization-prepared FLAIR and 44 with magnetization-prepared FLAIR). CSF hyperintensity was scored from 0 to 3 points according to the degree of CSF signal intensity and was compared between the 2 sequences. The contrast-to-noise ratios among GM, WM, and CSF were evaluated to assess general image quality from both sequences. To assess the diagnostic accuracy for hemorrhage, we reviewed an additional 25 patients with hemorrhage.
  
  
  
  Bloch simulation demonstrated that CSF hyperintensity can be reduced on magnetization-prepared FLAIR compared with non-magnetization-prepared FLAIR. CSF hyperintensity scores were significantly lower in magnetization-prepared FLAIR than in non-magnetization-prepared FLAIR (P < .01). The contrast-to-noise ratios for GM-WM, GM-CSF, and WM-CSF were significantly higher in magnetization-prepared FLAIR than in non-magnetization-prepared FLAIR (P < .05). Hemorrhage was clearly demarcated from CSF hyperintensity in the magnetization-prepared group (100%, 12/12) and non-magnetization-prepared group (38%, 5/13).
  
  
  
  Magnetization-prepared 3D-FLAIR MR imaging can significantly reduce oxygen-induced CSF artifacts and increase the tissue contrast-to-noise ratio beyond the levels achieved with conventional non-magnetization-prepared 3D-FLAIR MR imaging.
authors.affiliation: From Philips Korea (H.-K.J.), Seoul, Republic of Korea Korea Basic Science Institute (H.-K.J.), Chungcheongbuk-do, Republic of Korea.
authors.forename: H-K
authors.identifier: 0000-0002-6037-8342
authors.initials: HK
authors.lastname: Jeong
authors.affiliation: Department of Radiology (S.W.O), Soonchunhyang University Cheonan Hospital, Cheonan, Chungnam, Korea.
authors.forename: S W
authors.identifier: 0000-0003-1336-4498
authors.initials: SW
authors.lastname: Oh
authors.affiliation: Department of Radiology (J.K., S.-K.L., S.J.A.), Yonsei University College of Medicine, Seoul, Korea.
authors.forename: J
authors.identifier: 0000-0002-9978-4356
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Radiology (J.K., S.-K.L., S.J.A.), Yonsei University College of Medicine, Seoul, Korea.
authors.forename: S-K
authors.identifier: 0000-0001-5646-4072
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Department of Radiology (J.K., S.-K.L., S.J.A.), Yonsei University College of Medicine, Seoul, Korea. aahng77@yuhs.ac.
authors.forename: S J
authors.identifier: 0000-0003-0075-2432
authors.initials: SJ
authors.lastname: Ahn
mesh_terms: D000328:Adult; D016477:Artifacts; D002555:Cerebrospinal Fluid / Q000000981:diagnostic imaging* / Q000187:drug effects*; D002648:Child; D016292:Procedural Sedation; D054810:Deep Sedation; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008578:Meninges / Q000000981:diagnostic imaging; D008875:Middle Aged; D010100:Oxygen; D012189:Retrospective Studies
chemical_list: D010100:Oxygen