engleski

Spatial and temporal parameters of selective vulnerability of cerebrum in preterm infant (MRIi-histological correlation)

The goal of this review was to discuss the evidence related to the basic hypothesis which is: the vulnerability of the cerebrum in preterms is determined by transient cellular elements and transient patterns of laminar organization. It was found that the most important spatial factors of vulnerability are periventricular crossroads of projection, commissural and associative pathways, growing axonal strata in periventricular zone and growing axonal front in the transient subplate zone. The new, hitherto neglected element at extracellular-cellular level is sulfated proteoglycan matrix, adhesion molecules and axonal guidance molecules transiently expressed in periventricular crossroads and the subplate zone. The crucial temporal factors (developmental windows) are playing role during 22-26 weeks of gestation for thalamocortical and 28-32 weeks of gestation for callosal fibers, when structural plasticity (rerouting and detouring) can change projection to cortex. It was concluded that abnormalities in ECM and disturbances of axonal guidance molecules needed for growth of pathways together with the topography of crossroads of periventricular projection, associative and commissural fibres correlate well with the distribution of focal periventricular leukomalacia, while the distribution of ECM, adhesion and guidance molecular markers in the subplate correlates with the distribution of DEHSI. Although the cellular targets are not known, it is obvious that products of ischemic and inflammatory insults damage both oligodendrocytes and growing axons, leading ultimately to the reduction of the periventricular white matter.

axonal strata; subplate zone; periventricular leukomalacia; white matter injury; high-signal intensity

nije evidentirano