Assessing Early Brain Development in Neonates by Segmentation of High-Resolution 3T MRI
1,2G Gerig, 2M Prastawa, 3W Lin, 1John Gilmore Departments of 1Psychiatry, 2Computer Science, 3Radiology
University of North Carolina, Chapel Hill,NC 27614, [email protected] / http://www.cs.unc.edu/~gerig
SUMMARY
METHODS
• It is feasible to study brain development in unsedated newborns using 3T MRI
• Study will likely provide a vastly improved understanding of early brain development and its relationship to neuropsychiatric disorders.
• Novelty: Tissue model for segmentation of myelinated/nonmyel. white matter.
CONCLUSIONS
RESULTS
T1-only segmentation
Building of Atlas Template
MICCAI Nov. 2003
• Research: Quantitative MRI to study unsedated newborns at risk for neurodevelopmental disorders.
• Clinical Study: 120 newborns recruited at UNC, age at MRI about 2 weeks
• Motivation: Early detection of abnormalities Possibility for early intervention and therapy.
• Imaging: High field (3T Siemens Allegra), high resolution (T1 1mm3, FSE 0.9x0.9x3mm3), high-speed imaging (12’ for T1, FSE and DTI).
• So far: 20 normal neonates (10 males, 10 females)
• Age 16 ± 4 days• Siemens 3T head-only scanner• Neonates were fed prior to scanning,
swaddled, fitted with ear protection and had their heads fixed in a vac-fix device
• A pulse oximeter was monitored by a physician or research nurse
• Most neonates slept during the scan• Motion-free scans in 13-15 infants
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cases
Brain Tissue Volume Neonates
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csf
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T1 3D MPRage1x1x1 mm3
FSE T2w1x1x3 mm3
FSE PDw1x1x3 mm3
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Template MRI white matter csfgray matter
Tissue Probability Maps
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earlymyelinatedcorticospinaltract
hyper-intensemotor cortex
NeonateAdult
Approach:
• Atlas-moderated EM segmentation (cf. Leemput and Warfield)
• Tissue intensity model for white matter (non-myelinated and myelinated wm form bimodal distribution) (cf. Cocosco, Prastawa)
• Challenge: Very low CNR, heterogeneous tissue, early myelination regions, reverse contrast wm/gm.
• Standard brain tissue segmentation fails.
Preliminary Results UNC Neonate Study
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PD/T2 segmentation
High-resolution PD/T2 data courtesy of Petra Hueppi, Univ. of Geneva.
Supported by NIH Conte Center MH064065, Neurodevelopmental Disorders Research Center HD 03110 and the Theodore and Vada Stanley Foundation
Literature
• Gilmore JH, Gerig G, Specter B, Charles HC, Wilber JS, Hertzberg BS, Kliewer MA (2001a): Neonatal cerebral ventricle volume: a comparison of 3D ultrasound and magnetic resonance imaging. Ultrasound Med and Biol 27:1143-1146.
• Huppi PS, Warfield S, Kikinis R, Barnes PD, Zientara GP, Jolesz FA, Tsuji MK, Volpe JJ (1998b): Quantitative magnetic resonance imaging of brain development in premature and normal newborns. Ann Neurol 43: 224-235.
• Zhai G, Lin W, Wilber K, Gerig G, Gilmore JH (2003): Comparisons of regional white matter fractional anisotrophy in healthy neonates and adults using a 3T head-only scanner. Radiology (in press).
• Warfield, S., Kaus, M., Jolesz, F., Kikinis, R.: Adaptive template moderated spa-tially varying statistical classification. In Wells, W.M.e.a., ed.: Medical Image Computing and Computer-Assisted Intervention (MICCAI’98). Volume 1496 of LNCS., Springer 1998
• Van Leemput, K., Maes, F., Vandermeulen, D., Suetens, P.: Automated model-based tissue classification of MR images of the brain. IEEE Transactions on Medical Imaging 18 (1999) 897–908
• Cocosco, C.A., Zijdenbos, A.P., Evans, A.C.: Automatic generation of training data for brain tissue classification from mri. In Dohi, T., Kikinis, R., eds.: Medical Image Computing and Computer-Assisted Intervention MICCAI 2002. Volume 2488 of LNCS., Springer Verlag (2002) 516–523
• Prastawa, M., Bullitt, E., Gerig, G., Robust Estimation for Brain Tumor Segmentation, MICCIA 2003, Nov. 2003