The method we have developed to extract and label
from 3-D MRI the
cortical topography is divided in three steps :
**a)** extraction of the exterior trace of the
sulci and detection of the connections between
these entities. At this level, we extract the
superficial structural component of the cortical
topography ;
**b)** modelling of the deeper cortical infolding
by tracking the median surface of each cortical fold ( *fig 1.a*). As a
result, we obtain a parametric surface representing
the 3-D shape of the buried part of each sulcus [2].
Finally, a set of parameters are associated
with each extracted fold and junction, and the
result is encoded in a graph structure.
**c)** labelling
of these graphs were then performed by an anatomist through
an iteractive display interface for 51 subjects
in order to study the spatial distributions of the cortical
sulci. Data expressed with respect to
a standardized brain coordinate system (i.e Talairach-like coordinate system)
permits the creation of SP_AMs (Statistical Probability
Anatomy Map)[1] of the main sulci (*fig 1.b*).
These SP_AMs, representing the normal
spatial variability
of the neuroanatomy are then used
to perform the recognition of these
anatomical structures on a new subject (*fig 1.c*)