Morphology of the lateral fossa of the brain (sylvian valley): anatomo-radiological aspects and surgical application.

Introduction: The knowledge acquired on the lateral fossa of the brain (LFB) is heterogeneous and incomplete. Our goal was to provide a morphological description of the LFB and analyze the impact of these descriptions on the surgical approach of the region.

Methods: The morphology of LFB was studied on 40 cerebral hemispheres of 20 right-handed subjects aged 18-55 years with an MRI of 1.5 T. The anatomo-radiological identification of the two section levels preceded the description of the shapes of the LFB. From these landmarks, the forms presented by the LFB were identified and described on each of the transverse, sagittal and frontal planes. The comparison of the proportion of shapes made it possible to identify the typical shapes at each section level and on each section plane.

Results: The average age of the subjects was 33 years with extremes of 19 and 54 years including 7 women and 13 right-handed men. According to the plane and the level of section, 6 typical morphologies of the LFB have been described, 2 of which were identical. The forms did not vary according to the cerebral hemisphere or the sex of the subject. The set of typical morphologies made it possible to determine a reference subject called NSK which presented the greatest number of typical morphological characteristics.

Conclusion: Knowledge of LFB anatomical imaging is of paramount importance in the pre-surgical evaluation of pathologies in this region. The reference subject will be used for our future biometric and three-dimensional manual reconstruction work in this region.