title: Diffusion tensor imaging in patients with acute onset of neuropsychiatric systemic lupus erythematosus: a prospective study of apparent diffusion coefficient, fractional anisotropy values, and eigenvalues in different regions of the brain.
abstract: OBJECTIVE
  To investigate whether apparent diffusion coefficient (ADC), fractional anisotropy (FA), and eigenvalues in neuropsychiatric systemic lupus erythematosus (NPSLE) patients differ from those of healthy controls.
  
  
  METHODS
  Eight NPSLE patients (aged 23-55 years, mean 42.9 years) and 20 healthy age-matched controls (aged 22-59 years, mean 44.4 years) underwent conventional brain magnetic resonance (MR) and diffusion tensor imaging (DTI). The ADC, FA, principal eigenvalue (lambda parallel), and the corresponding average perpendicular eigenvalue (lambda perpendicular) (=(lambda2+lambda3)/2) were measured in selected regions of normal appearing gray and white matter brain parenchyma. For statistical evaluation of differences between the two groups, a Student's t-test was used. The P value for statistical significance was set to P=0.0025 after Bonferroni correction for multiple measurements.
  
  
  RESULTS
  Significantly increased ADC values were demonstrated in normal-appearing areas in the insular cortex (P<0.001), thalamus (P<0.001), and the parietal and frontal white matter (P<0.001 and P<0.001, respectively) in NPSLE patients. Significantly decreased FA values were demonstrated in normal-appearing thalamus (P<0.001), corpus callosum (P=0.002), and in the parietal and frontal white matter (P<0.001 and P<0.001, respectively) in NPSLE patients compared to healthy controls. The lambda perpendicular was significantly higher in several of these regions in NPSLE patients compared to healthy controls.
  
  
  CONCLUSIONS
  Our study demonstrates alterations in normal-appearing gray and white matter brain parenchyma of patients with NPSLE by means of abnormal ADC, FA, and eigenvalues. These alterations may be based on loss of tissue integrity in part due to demyelination. It is possible that DTI in the future could assist in the diagnosis of NPSLE and possibly help to further elucidate the pathogenesis of NPSLE.
authors.affiliation: Department of Radiology, School of Public Health, University of Michigan Health Systems, Ann Arbor, Michigan 48109, USA.
authors.forename: M
authors.initials: M
authors.lastname: Hughes
authors.forename: P C
authors.initials: PC
authors.lastname: Sundgren
authors.forename: X
authors.initials: X
authors.lastname: Fan
authors.forename: B
authors.initials: B
authors.lastname: Foerster
authors.forename: B
authors.initials: B
authors.lastname: Nan
authors.forename: R C
authors.initials: RC
authors.lastname: Welsh
authors.forename: J A
authors.initials: JA
authors.lastname: Williamson
authors.forename: J
authors.initials: J
authors.lastname: Attwood
authors.forename: P V
authors.initials: PV
authors.lastname: Maly
authors.forename: T L
authors.initials: TL
authors.lastname: Chenevert
authors.forename: W
authors.initials: W
authors.lastname: McCune
authors.forename: S
authors.initials: S
authors.lastname: Gebarski
mesh_terms: D000208:Acute Disease; D000328:Adult; D016880:Anisotropy; D016022:Case-Control Studies; D003287:Contrast Media / Q000008:administration & dosage; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D020945:Lupus Vasculitis, Central Nervous System / Q000473:pathology*; D008297:Male; D008875:Middle Aged
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA