The Fetus & Developing Brain
Wednesday 22 April 2009
Room 311 13:30-15:30

Moderators:

 Nadine J. Girard and Jeffrey Joseph Neil
 
13:30 488. Optimisation of a Balanced Fast Field Echo Cine Sequence for the Assessment of Human Fetal Motor Function
    Tayyib Hayat1,2, Joanna Allsop1, Amy McGuinness1, Fabrizio Ferrari3, Mary Rutherford1,2, Joseph V. Hajnal1
1Robert Steiner MRI Unit, Imaging Sciences Department, MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, UK; 2Perinatal Imaging Group, MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, UK; 3Department of Pediatrics and Neonatology, Modena University Hospital, Italy
    The analysis of motor function is an important element of the neurological assessment of human neonates, with General Movements (GM) being a recognised pattern that is clinically useful in diagnosing abnormal infants. To assess GM, the whole infant must be observed. Attempts to study fetal GM in utero by ultrasound have been hindered by limitations in the field-of-view, particularly later in pregnancy. We have optimised a MR cine sequence for imaging the whole fetus throughout gestation and performed a pilot study that shows differences in movement quality with age and a neurological condition.
     
13:42 489. The Evolution of Brain Functional Architecture from the Age of 2 Weeks to 2 Years
    Wei Gao1, Hongtu Zhu2, Kelly Giovanello3, Keith Smith4, Dinggang Shen5, John Gilmore6, Weili Lin5
1Department of Biomedical Engineering, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA; 2Department of Biostatistics and BRIC, University of North Carolina-Chapel Hill; 3Department of Psychology and BRIC, University of North Carolina-Chapel Hill; 4Department of Radiology, University of North Carolina-Chapel Hill; 5Department of Radiology and BRIC; 6Department of Psychiatry, University of North Carolina-Chapel Hill
    Human brain is intrinsically organized as a functionally connected network, facilitating efficient information integration, processing and decision making. This study shows the evolution of this network from the age of 2 weeks to 2 years.
     
13:54 490.

Differences in Blood Perfusion Between Extremely Low Birth Weight (ELBW) Pre-Term Infants and Control Term Infants
    Arvind Caprihan1, U. Sakoglu1, J. Pfeuffer2, J. Rael3, J. Stephen1, J. Lowe3, S. Duvall1, C. Gasparovic1, R.K. Ohls3, J P. Phillips1,3
1The Mind Research Network, Albuquerque, NM, USA; 2Siemens Medical Solutions USA, Inc, Charlestown, MA, USA; 3University of New Mexico, Albuquerque, NM, USA
    Reduced blood perfusion is one of the causes of ischemic brain injury in extremely low birth weight (ELBW) infants. One potential new therapy to reduce or prevent brain injury is the use of human recombinant erythropoietin (Epo). We compare neurodevelopmental outcomes with brain blood perfusion distribution in preterm infants who received Epo during their hospitalization, compared to preterm infants who did not, and compared with healthy term controls. This is an ongoing blind study and at present we report on blood perfusion measurements by pulsed arterial spin labeling (PASL) in ELBW infants and healthy term controls.
     
14:06 491. Development of Major White Matter Tracts in Fetal Brains Revealed by DTI
    Hao Huang1, Linda J. Richards2, Paul Yarowsky3, Susumu Mori4,5
1Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, USA; 2Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia; 3Pharmacology and Experimental Therapeutics, University of Maryland, Baltimore, MD, USA; 4Radiology, Johns Hopkins University, Baltimore, MD, USA; 5F.M. Kirby Functional MRI Center, Kennedy Krieger Institute, Baltimore, MD, USA
    The human fetal brain development is characterized with dramatic structural changes. Specifically during the second trimester, some important white matter tracts begin to form and the existing tracts undergo significantly morphological changes. DTI colormap and tractography are capable of revealing the white matter changes. In this study, DTI data of postmortem human fetal brains from 13 to 22 gestational weeks were acquired for structural annotation and tractography. Tracts in brain stem and limbic tracts develop early and before second trimester. During second trimester, corpus callosum, uncinate, inferior fronto-occipital and inferior longitudinal fasciculus begin to form.
     
14:18 492. Following the Development of Corpus Callosum (CC) in the Prenatal Period in Humans Through Diffusion Tensor Tractography (DTT)
    Richa Trivedi1, Sona Saksena1, Shruti Agarwal2, Nuzhat Husain3, Ram K  S Rathore2, Rakesh K. Gupta1
1Department of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India; 2Department of Mathematics and Statistics, Indian Institute of Technology, Kanpur, India; 3Neuropathology, Chhatrapati Sahuji Maharaj Medical University, Lucknow, India
    DTT using FACT Algorithm was performed on 20 normal human fetal brains with age ranging from 16 to 40 weeks of gestational age (GA) to study the normal appearance and development of CC. Quadratic model was considered to examine the trends in callosal FA with increasing GA. A significant positive correlation was observed between callosal bundle FA values and GA. Beyond 19 weeks of GA, CC formed a shape like adult form only in terms of superficial appearance that further showed increment in both fiber length and thickness with age. The ability to noninvasive monitoring of CC development in vivo should greatly improve our understanding of the normal developmental pattern of CC in human fetal brain that may be used as a reference for the diagnosis of developmental defects of the CC.
     
14:30 493. Quantitative Diffusion Tensor Tractography (DTT) of Motor and Sensory White Matter Pathways in Cerebral Palsy
    Richa Trivedi1, Shruti Agarwal2, Vipul Shah3, Vimal K. Paliwal4, Ram K  S Rathore2, Rakesh K. Gupta1
1Department of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India; 2Department of Mathematics and Statistics, Indian Institute of Technology, Kanpur, India; 3Pediatric Orthopedic Surgery unit, Bhargava Nursing Home, Lucknow, India; 4Department of Neurology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India
    DTT using FACT Algorithm was performed on 39 children with cerebral palsy (CP) (8 years mean age) as well as 14 age/ sex matched healthy controls. Free hand ROIs for FA and MD quantitation were drawn on axial T2 image near the brain’s vertex on the precentral and postcentral gyri, and were defined as motor or sensory tracts, respectively. Based on the present study, it appears that patients with CP with normal imaging on conventional MRI have microstructural damage predominately in the sensory pathway. In conclusion, this quantitative DTT characterizes the trends in spatially averaged diffusivity and FA for the CP patients with normal as well as abnormal imaging in motor and sensory tracts.
     
14:42 494. Early White Matter Maturation: A Longitudinal Study of Normal Pediatric Subjects from the Age of 2 Weeks to 4 Years
    Yasheng Chen1, Hongtu Zhu2, Dinggang Shen1, Hongyu An1, John Gilmore3, Weili Lin1
1Radiology, UNC-CH, Chapel Hill, NC, USA; 2Biostatistics, UNC-CH, Chapel Hill, NC, USA; 3Psychiatry, UNC-CH, Chapel Hill, NC, USA
    This is a longitudinal study to quantify early white matter maturation patterns via diffusion tensor imaging (DTI). Twenty nine full-term, healthy babies were longitudinally scanned for a total of 71 data sets spanning from 2wks after birth to four-year-old. The changing patterns in four DTI parameters including fractional anisotropy, mean, radial and axial diffusivities were quantified through a generalized estimating equation based longitudinal analysis framework. We found that the genu of the corpus callosum has a more rapid myelination process when compared to the internal capsule and the splenium and body of the corpus callosum. The external capsule has a slower maturation pace compared to the corpus callosum and internal capsule.
     
14:54 495. White Matter Maturation in Healthy Children and Patients Treated with Brain Radiation: A Longitudinal DTI Study
    Firouzeh Tannazi1, Todd R. McNutt2, Siamak Ardekani3, Moody D. Wharam2, Alena Horska1
1The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; 2Radiation Oncology & Molecular Radiation Sciences, Johns Hopkins University, Baltimore, MD, USA; 3Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA
    A longitudinal DTI study with 3 follow-up examinations (over a 27 month period) was conducted to examine brain maturation of selected white matter regions in healthy children and adolescents, and pediatric patients who received radiation therapy for brain malignancies. Healthy children demonstrated regional age-related decrease in ADC and increase in FA. In children who received radiation therapy, regional increase in ADC, decline in FA, and increase in radial diffusivity was detected consistent with radiation-induced demyelination.
     
15:06 496. Voxel Based Analysis of Diffusion Indices and Deformation Based Volumetric Alterations in Late Childhood and Adolescence
    Siamak Ardekani1, Firouzeh Tannazi2, Alena Horska2
1Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA; 2The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
    Changes in white matter microstructure and brain tissue volume during late childhood and early adolescence were studied using voxel-based analysis of diffusion parameters and deformation-based volumetric measures, utilizing a non-linear registration algorithm. Fifteen healthy children were examined longitudinally, at baseline and a 15 month follow-up. Statistical analyses revealed significant ADC decrease and FA increase, and axial and radial diffusivity decline in several regions (internal and external capsule, forceps minor, and corona radiata). A trend to increased tissue volume was also detected in several regions. These results suggest continuation of regional brain maturation and increase in fiber density during late childhood.
     
15:18 497. Multimodality Neuroimaging to Study Tourette Syndrome: Correlating AMT-PET and DT-MRI
    Anita SD Saporta1, Malek I. Makki2, Benjamin J. Wilson1, Michael E. Behen1, Otto Muzik1, Csaba Juhasz1, Harry T. Chugani1
1Pediatrics, Wayne State University, Detroit, MI, USA; 2Radiology, Wayne State University, Detroit, MI, USA
    To study serotonin-metabolism and microstructure associations in caudate nucleus (CN) and thalamus (TH), components of cortico-striato-thalamic-circuit affected in Tourette-Syndrome (TS), 15 children with TS underwent AMT-PET and DT-MRI scans. Eigenvalues, FA, ADC, linear, planar, and spherical (Cs) indices were obtained. Coregistration of both scans was performed to delineate those structures. Pearson-correlation analyses of the asymmetry index (AI) of AMT and DTI showed negative correlation between AMT and FA (r= -0.744;p=0.001) and positive correlation between AMT and Cs (r=0.594;p=0.019) in CN, but none in TH. Our findings will help to track neuronal/axonal/dendritical changes and to obtain a better understanding of TS.