title: Right arcuate fasciculus abnormality in chronic fatigue syndrome.
abstract: OBJECTIVE
  To identify whether patients with chronic fatigue syndrome (CFS) have differences in gross brain structure, microscopic structure, or brain perfusion that may explain their symptoms.
  
  
  METHODS
  Fifteen patients with CFS were identified by means of retrospective review with an institutional review board-approved waiver of consent and waiver of authorization. Fourteen age- and sex-matched control subjects provided informed consent in accordance with the institutional review board and HIPAA. All subjects underwent 3.0-T volumetric T1-weighted magnetic resonance (MR) imaging, with two diffusion-tensor imaging (DTI) acquisitions and arterial spin labeling (ASL). Open source software was used to segment supratentorial gray and white matter and cerebrospinal fluid to compare gray and white matter volumes and cortical thickness. DTI data were processed with automated fiber quantification, which was used to compare piecewise fractional anisotropy (FA) along 20 tracks. For the volumetric analysis, a regression was performed to account for differences in age, handedness, and total intracranial volume, and for the DTI, FA was compared piecewise along tracks by using an unpaired t test. The open source software segmentation was used to compare cerebral blood flow as measured with ASL.
  
  
  RESULTS
  In the CFS population, FA was increased in the right arcuate fasciculus (P = .0015), and in right-handers, FA was also increased in the right inferior longitudinal fasciculus (ILF) (P = .0008). In patients with CFS, right anterior arcuate FA increased with disease severity (r = 0.649, P = .026). Bilateral white matter volumes were reduced in CFS (mean ± standard deviation, 467 581 mm(3) ± 47 610 for patients vs 504 864 mm(3) ± 68 126 for control subjects, P = .0026), and cortical thickness increased in both right arcuate end points, the middle temporal (T = 4.25) and precentral (T = 6.47) gyri, and one right ILF end point, the occipital lobe (T = 5.36). ASL showed no significant differences.
  
  
  CONCLUSIONS
  Bilateral white matter atrophy is present in CFS. No differences in perfusion were noted. Right hemispheric increased FA may reflect degeneration of crossing fibers or strengthening of short-range fibers. Right anterior arcuate FA may serve as a biomarker for CFS.
authors.affiliation: From the Department of Radiology, Lucas Center for Imaging, Stanford University School of Medicine, 1201 Welch Rd, Room P271, Stanford, CA 94305-5488.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Zeineh
authors.forename: James
authors.initials: J
authors.lastname: Kang
authors.forename: Scott W
authors.initials: SW
authors.lastname: Atlas
authors.forename: Mira M
authors.initials: MM
authors.lastname: Raman
authors.forename: Allan L
authors.initials: AL
authors.lastname: Reiss
authors.forename: Jane L
authors.initials: JL
authors.lastname: Norris
authors.forename: Ian
authors.initials: I
authors.lastname: Valencia
authors.forename: Jose G
authors.initials: JG
authors.lastname: Montoya
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000002:abnormalities*; D056324:Diffusion Tensor Imaging; D015673:Fatigue Syndrome, Chronic / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009415:Nerve Net; D012189:Retrospective Studies; D013113:Spin Labels; D066127:White Matter; D055815:Young Adult
chemical_list: D013113:Spin Labels