Preliminary Results Longitudinal Change

1
Preliminary Results Longitudinal Change
The most striking result of the longitudinal
growth analysis between 2 and 4 years is the
apparent cerebral asymmetry and brain torque.
There is a consistent right frontal gt left
frontal and a left posterior parietal/occipital gt
right posterior parietal/occipital pattern,
commonly called torque or brain torsion. The
temporal lobes show a similar pattern as the
frontal lobes, with right temporal gt left
temporal growth. Local growth is mostly evident
in cortical gray, which seems to account for the
major brain growth. Lateral ventricles are
stable, but the third ventricle illustrates a
significant width reduction, along with a closing
of the ascending ramus of the Sylvian fissure.
Brain surface illustration of local brain growth
between 2yrs and 4yrs. Growth is most apparent in
right frontal and left occipital cortex and in
general in cortical gray.
growth
shrinkage
Preliminary Results Group Tests
Cross-sectional group difference analysis between
Typ and Aut
Typ gt Aut
Typ lt Aut
Group tests between TYP and AUT subjects at age 2
(left) and age 4 (right) reveal a strong group
difference of the cerebellum, which is much more
pronounced at age 2 and lessens towards age 4.
Design of cross-sectional and longitudinal group
tests. Atlases are created for the autism and
control groups at age 2 and 4yrs. We used 5
images in each group for this preliminary
feasibility study.
Conclusions
Our preliminary findings indicate that the new
methodology shows excellent potential to explore
longitudinal change, difference between groups,
and differences between growth trajectories
between groups. The simultaneous analysis of the
whole volumetric brain is a major strength, as it
will reveal morphometric changes of structures
with embedding context, e.g. studying cortical
growth in relationship to adjacent white matter,
and examining groups of subcortical structures
and even whole circuits. We are currently
confirming these exploratory findings with larger
samples. Gender differences could not yet be
explored due to the small sample size.
Literature

• Sarang Joshi, Brad Davis, Matthieu Jomier, and
  Guido Gerig, "Unbiased Diffeomorphic Atlas
  Construction for Computational Anatomy,"
  NeuroImage Supplement issue on Mathematics in
  Brain Imaging, (PM Thompson, MI Miller, T
  Ratnanather, RA Poldrack, and TE Nichols, eds.),
  vol. 23, no. Supplement1, pp. S151-S160,
  Elsevier, Inc, 2004.
• Peter Lorenzen, Marcel Prastawa, Brad Davis,
  Guido Gerig, Elizabeth Bullitt, and Sarang Joshi,
  Multi-Modal Image Set Registration and Atlas
  Formation, Medical Image Analysis MEDIA,
  Elsevier, in press
• Peter Lorenzen, Brad Davis, Guido Gerig,
  Elizabeth Bullitt and Sarang Joshi, "Multi-class
  Posterior Atlas Formation via Unbiased
  Kullback-Leibler Template Estimation", Lecture
  Notes in Computer Science LNCS 3216, Springer
  Verlag, pp. 95-102, 2004.
• B Davis, P Lorenzen, and S Joshi, "Large
  Deformation Minimum Mean Squared Error Template
  Estimation for Computational Anatomy," in
  International Symposium on Biomedical Imaging
  (ISBI) Proceedings, (Piscataway, NJ), pp.
  173-176, Apr. 2004.

Acknowledgements
Supported by the NIH Conte Center MH064065, the
Neurodevelopmental Disorders Research Center HD
03110, the NIH RO1 MH61696, and NIBIB grant P01
EB002779