title: Vigabatrin-associated reversible MRI signal changes in patients with infantile spasms.
abstract: OBJECTIVE
  To evaluate the magnetic resonance imaging (MRI) of pediatric patients with infantile spasms (IS) treated with vigabatrin (VGB) in order to investigate whether VGB affects the brain.
  
  
  METHODS
  One hundred seven pediatric patients diagnosed with IS and treated with (n = 95) >or=120 mg/kg/day VGB or without (n = 12) VGB were included. MRI and diffusion-weighted imaging (DWI) were retrospectively analyzed.
  
  
  RESULTS
  Of the patients who had MRI scans during, but not before, VGB treatment (n = 81), 25 (30.9%) exhibited abnormal MRI signal intensity and/or restricted DWI in the deep gray nuclei and brainstem. Follow-up scans (performed in 15 of the 25 patients) revealed that these changes were reversible upon withdrawal of the medication. Analysis of patients undergoing scans before, during, and after VGB treatment (n = 14) revealed that four patients had abnormal MRI signal during treatment with VBG, two of whom reversed with cessation of VGB, one reversed without cessation of VGB, and another had persistent abnormal signal while being weaned from the VGB. Patients who had not received VGB treatment (n = 12) displayed normal imaging. Younger infants (<or=12 months) and those with cryptogenic IS were more likely to develop abnormal signal changes on MRI during VGB treatment.
  
  
  CONCLUSIONS
  In pediatric patients, VGB induces reversible MRI signal changes and reversible diffusion restriction in the globi pallidi, thalami, brainstem, and dentate nuclei. The risk for this phenomenon was greater in younger infants and patients with cryptogenic IS.
authors.affiliation: Department of Ophthalmology & Vision Sciences, The Hospital for Sick Children, Toronto, Ontario, Canada. aphrodite.dracopoulos@gmail.com
authors.forename: Aphrodite
authors.initials: A
authors.lastname: Dracopoulos
authors.forename: Elysa
authors.initials: E
authors.lastname: Widjaja
authors.forename: Charles
authors.initials: C
authors.lastname: Raybaud
authors.forename: Carol A
authors.initials: CA
authors.lastname: Westall
authors.forename: O Carter
authors.initials: OC
authors.lastname: Snead
mesh_terms: D002648:Child; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies; D013036:Spasms, Infantile / Q000175:diagnosis* / Q000188:drug therapy*; D020888:Vigabatrin / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D020888:Vigabatrin