title: Age-related distribution of vertebral bone-marrow diffusivity.
abstract: OBJECTIVE
  To determine age-related diffusivity changes of the lumbar bone marrow by measurement of apparent diffusion coefficient (ADC) values.
  
  
  METHODS
  The local ethics committee approved this study and written informed consent was obtained. The study group comprised 88 individuals including 75 healthy volunteers and 13 patients (48 female, 40 male; mean age 36 years, range 0-84 years). The pediatric cases were recruited from patients. Echo-planar diffusion weighted imaging (DWI) was performed with b-values of 50, 400 and 800 s/mm(2). ADC-values were calculated and measured in the 1st and 2nd vertebral body of the lumbar spine. Correlation between age and ADC-values was analyzed with Spearman's rho test.
  
  
  RESULTS
  The ADC values of the vertebral bone marrow of the lumbar spine showed a significant negative correlation with age (rho=-0.398, p=0.001). The mean ADC values (×10(-3)mm(2)/s) in the age groups 0-29 years (mean age 18.0 years, n=42) and 30-88 years (mean age 51.6 years, n=46) were 0.54 ± 0.07 and 0.47 ± 0.08, respectively (p<0.001, T-test). No significant differences were found between children and young adults.
  
  
  CONCLUSIONS
  Bone marrow ADC values of the lumbar spine show a linear decrease with growing age and thereby reflect the gradual changes of cell composition occurring during marrow conversion.
authors.affiliation: Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg, Germany. j.herrmann@uke.de
authors.forename: Jochen
authors.initials: J
authors.lastname: Herrmann
authors.forename: Nina
authors.initials: N
authors.lastname: Krstin
authors.forename: Bjoern P
authors.initials: BP
authors.lastname: Schoennagel
authors.forename: Marjike
authors.initials: M
authors.lastname: Sornsakrin
authors.forename: Thorsten
authors.initials: T
authors.lastname: Derlin
authors.forename: Jasmin D
authors.initials: JD
authors.lastname: Busch
authors.forename: Kay Uwe
authors.initials: KU
authors.lastname: Petersen
authors.forename: Joachim
authors.initials: J
authors.lastname: Graessner
authors.forename: Gerhard
authors.initials: G
authors.lastname: Adam
authors.forename: Christian R
authors.initials: CR
authors.lastname: Habermann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D001853:Bone Marrow / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007223:Infant; D007231:Infant, Newborn; D008159:Lumbar Vertebrae / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult