Analysis of cerebellar changes in shape and size along development by using geometric morphometrics coordinates

Abstract

The cerebellar anlage is subject to a multifactorial process, with intrinsic and extrinsic factors, to acquire a complex adult morphological structure. The spectacular cortical development provokes dramatic changes in shape and size of the initial structure, that course with the formation of folia and fissures. The study of these transformations from a global point of view is the goal of the present study. For this approach, midsagittal sections of chick embryonic cerebella from stages HH36 to HH44 were used to obtain sets of landmarks analyzed by geometric morphometrics. This tool exploits not only the morphology per se, but the spatial relationships of anatomical structures in a quantitative and visual way. Preliminary results indicate that changes in the cerebellum are mainly observed at the transition between stages HH37-HH38, HH39-HH40 and HH40-HH41. The observed changes are summarized: 1)- the cavum ventricularis is progressively reduced to be converted into a cleft; 2)- centrifugal expansion of the folia, specially from HH40 onwards; 3)- fixation of the base of the fissures to the cerebellum core during the centrifugal expansion of the folia.