title: Brain size and white matter content of cerebrospinal tracts determine the upper cervical cord area: evidence from structural brain MRI.
abstract: BACKGROUND
  Measurement of the upper cervical cord area (UCCA) from brain MRI may be an effective way to quantify spinal cord involvement in neurological disorders such as multiple sclerosis. However, knowledge on the determinants of UCCA in healthy controls (HCs) is limited.
  
  
  METHODS
  In two cohorts of 133 and 285 HCs, we studied the influence of different demographic, body-related, and brain-related parameters on UCCA by simple and partial correlation analyses as well as by voxel-based morphometry (VBM) across both cerebral gray matter (GM) and white matter (WM).
  
  
  RESULTS
  First, we confirmed the known but moderate effect of age on UCCA in the older cohort. Second, we studied the correlation of UCCA with sex, body height, and total intracranial volume (TIV). TIV was the only variable that correlated significantly with UCCA after correction for the other variables. Third, we studied the correlation of UCCA with brain-related parameters. Brain volume correlated stronger with UCCA than TIV. Both volumes of the brain tissue compartments GM and WM correlated with UCCA significantly. WM volume explained variance of UCCA after correction for GM volume, whilst the opposite was not observed. Correspondingly, VBM did not yield any brain region, whose GM content correlated significantly with UCCA, whilst cerebral WM content of cerebrospinal tracts strongly correlated with UCCA. This latter effect increased along a craniocaudal gradient.
  
  
  CONCLUSIONS
  UCCA is mainly determined by brain volume as well as by WM content of cerebrospinal tracts.
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Engl
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany.|Department of Statistics, Ludwig-Maximilians-University München, Munich, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Schmidt
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Milan
authors.initials: M
authors.lastname: Arsic
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Christine C
authors.initials: CC
authors.lastname: Boucard
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Viola
authors.initials: V
authors.lastname: Biberacher
authors.affiliation: Department of Radiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.|Münchner Institut für Neuroradiologie, Munich, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Röttinger
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany.|Department of Neurology, Klinikum Traunstein, Traunstein, Germany.
authors.forename: Thorleif
authors.initials: T
authors.lastname: Etgen
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Nunnemann
authors.affiliation: Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Koutsouleris
authors.affiliation: Department of Radiology, Ludwig-Maximilians-Universität, Munich, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Reiser
authors.affiliation: Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Eva M
authors.initials: EM
authors.lastname: Meisenzahl
authors.affiliation: Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, Munich, Germany. muehlau@lrz.tum.de.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany. muehlau@lrz.tum.de.
authors.forename: Mark
authors.initials: M
authors.lastname: Mühlau
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D001921:Brain / Q000033:anatomy & histology*; D002574:Cervical Vertebrae / Q000033:anatomy & histology*; D015331:Cohort Studies; D019317:Evidence-Based Medicine; D005260:Female; D005858:Germany; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000648:ultrastructure*; D009474:Neurons / Q000166:cytology*; D009929:Organ Size; D011712:Pyramidal Tracts / Q000033:anatomy & histology*; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012737:Sex Factors; D055815:Young Adult