Morfometría de la fosa posterior durante el desarrollo postnatal temprano

VALLEJO AZAR MARIANA; ZURDO L; GARZON NICOLAS; HILGUERA FELIPE; BLANCO YENY; JAIMOVICH R; RUGILO C; BENDERSKY M; GONZALEZ, PAULA N.

Revista Argentina de Anatomía on line.

Sociedad Argentina de Anatomia

Año: 2018

Introduction: Defects in the normal development of the posterior fossa can give rise to numerous pathologies. However, no comprehensive studies of the morphometric variation of the fossa during early postnatal development have been performed yet. The posterior fossa is delimited in its upper part by the cerebellar tentorium and in its lower part by the foramen magnum. Between the two limits the following are found: the cerebellum, the bridge, the upper part of the medulla, the cranial pairs V to XII from their apparent origin andcisternal portions until their exit from the base of the skull. The cranialpart of the posterior fossa is formed in the inferior and posterior portion by the occipital bone and the clivus (formed by the union of the sphenoid with the occipital) which constitutes the anterior limit. Our objective is to characterize the metric variation of anatomical features of the posterior fossa and associated structures in individuals from 0 to 24 months of age without pathologies that affect the skull or the brain in a sample from Argentina.Materials and methods: A sample of 185 computer tomography images of normal skulls of individuals of both sexes between 0 and 24 months was retrospectively analyzed. We measured the area of the posterior fossa, tentorial angle, magna cistern area, clivus lenght,angle of the occipital segment and bulb-protuberance length on sagittal section. Descriptive statistics was applied to each variable, and then the degree of association between these variables and age was estimated. Finally, we assessed the existence of differences betweenmales and females.Results: The area of the posterior fossa, clivus length and the angle of the occipital segment showed significant changes with age. With the exception of cisterna magna area, all measurements taken on the posterior fossa resulted in significant sexual differences.Conclusions: In the range of 0 to 2 years, the tentorial angle and the cisterna magna area do not vary with age. The opposite occurs with the values of the area of the posterior fossa, which increased with the age of the individuals, indicating that the growth of the same continues during the postnatal period. After 7 months, a marked sexual dimorphism is observed in the area of the posterior fossa and the tentorial angle.