Correlation Between Anatomy and MRI

Abstract

This section describes the appearance of the HF as it grows postnatally, relating gross anatomical and microscopic features of the HF to its appearance in MRI images.

One of the main goals of this part of the study was to compare the MRI appearances of the HF structures with neuroanatomical section series, and to ascertain which specific components of the HF correspond to precise and recognizable landmarks in MRI images. In this way, the landmarks described in the gross anatomical chapter can be applied to the images to facilitate their interpretation in terms of specific components of the HF whenever possible. A secondary objective was to verify whether this comparison would allow the calculation of relative distances of landmarks along the medial temporal lobe, and particularly those related to the HF in the MRI series. Our aim was that this correlation should provide a guide for clinical MRI studies in the postnatal period of development of the human HF. To assess the longitudinal distances at which relevant structures of the HF were located, we chose to use the limen insulae or frontotemporal junction as a fixed starting point, as the temporal poles were not always available. Distances to the limen insulae of anatomical structures that are capable establishing the location and extent of the HF, amygdala and surrounding cortex (PHR) were calculated. Only those pertaining strictly to the HF are presented. For the MRI segmentation we applied our own previously described criteria and segmentation procedure to volumetric evaluation of the temporal pole, EC and PRC in MRI images in adults (Insausti et al. 1998b).