title: Atlas-free surface reconstruction of the cortical grey-white interface in infants.
abstract: BACKGROUND
  The segmentation of the cortical interface between grey and white matter in magnetic resonance images (MRI) is highly challenging during the first post-natal year. First, the heterogeneous brain maturation creates important intensity fluctuations across regions. Second, the cortical ribbon is highly folded creating complex shapes. Finally, the low tissue contrast and partial volume effects hamper cortex edge detection in parts of the brain.
  
  
  RESULTS
  We present an atlas-free method for segmenting the grey-white matter interface of infant brains in T2-weighted (T2w) images. We used a broad characterization of tissue using features based not only on local contrast but also on geometric properties. Furthermore, inaccuracies in localization were reduced by the convergence of two evolving surfaces located on each side of the inner cortical surface. Our method has been applied to eleven brains of one- to four-month-old infants. Both quantitative validations against manual segmentations and sulcal landmarks demonstrated good performance for infants younger than two months old. Inaccuracies in surface reconstruction increased with age in specific brain regions where the tissue contrast decreased with maturation, such as in the central region.
  
  
  CONCLUSIONS
  We presented a new segmentation method which achieved good to very good performance at the grey-white matter interface depending on the infant age. This method should reduce manual intervention and could be applied to pathological brains since it does not require any brain atlas.
authors: INSERM, Cognitive Neuroimaging Unit, Gif sur Yvette, France. francois.leroy@cea.fr
authors: François
authors: F
authors: Leroy
authors: Jean-François
authors: JF
authors: Mangin
authors: François
authors: F
authors: Rousseau
authors: Hervé
authors: H
authors: Glasel
authors: L
authors: L
authors: Hertz-Pannier
authors: Jessica
authors: J
authors: Dubois
authors: Ghislaine
authors: G
authors: Dehaene-Lambertz
mesh_terms: D002540:Cerebral Cortex; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000379:methods*