title: Epiphyseal marrow in infancy: MR imaging.
abstract: Hypointense epiphyseal marrow on T1-weighted magnetic resonance images often suggests disease. To determine whether hypointense marrow sometimes represents normal red marrow in a recently ossified epiphyseal center, the authors studied 38 infants without known marrow disease. Patients with hypointense epiphyseal marrow on T1-weighted images were younger (3.9 months +/- 3.2) than those with hyperintense marrow (9.6 months +/- 3.9) (P less than .001). T1-weighted imaging and histologic correlation were also performed in animals. The signal was hypointense and the marrow was red in the epiphyseal centers of all newborn animals, while all 6-week-old animals had hyperintense signal and yellow marrow. The authors conclude that hypointense marrow on T1-weighted images represents normal red marrow in a recently formed ossification center in newborn rabbits and lambs, and the same is probably true in humans. Epiphyseal marrow becomes hyperintense within a few months of development of the secondary center of ossification.
authors.affiliation: Department of Radiology, Children's Hospital, Boston, MA 02115.
authors.forename: D
authors.initials: D
authors.lastname: Jaramillo
authors.forename: T
authors.initials: T
authors.lastname: Laor
authors.forename: F A
authors.initials: FA
authors.lastname: Hoffer
authors.forename: D J
authors.initials: DJ
authors.lastname: Zaleske
authors.forename: R H
authors.initials: RH
authors.lastname: Cleveland
authors.forename: B R
authors.initials: BR
authors.lastname: Buchbinder
authors.forename: T K
authors.initials: TK
authors.lastname: Egglin
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000033:anatomy & histology; D001853:Bone Marrow / Q000033:anatomy & histology*; D004838:Epiphyses / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D010012:Osteogenesis; D011817:Rabbits; D012016:Reference Values; D012756:Sheep