Clinical and radiological features of patients with congenital basal encephaloceles involving functionally important structures: a series of observations

Relevance of the problem. In congenital transsphenoidal and sphenoethmoidal encephaloceles, several functionally important structures may be included in the hernial sac, such as the anterior cerebral artery, pituitary gland, optic nerve, and walls of the third ventricle. Our aim is to analyze a series of patients with these types of congenital basal encephaloceles in order to better understand the involvement of these structures and improve the accuracy of diagnosis and treatment planning. Material and methods. Clinical and radiological data of six patients who were treated at the Burdenko National Medical Research Center for Neurosurgery were analyzed. Craniometric analysis was used to determine characteristic concomitant deformities of the structures of the facial skeleton and the base of the skull. Results. All patients had impaired nasal breathing. No endocrine disorders, gross ophthalmological symptoms, or nasal liquorrhea, were recorded. Recurrent meningitis was not reported. Concomitant malformations were identified in four out of six patients. During an MRI scan, a hernial sac was observed, consisting of a protrusion from the anterior wall of the third ventricle, which is the area of the terminal plate. This anterior wall corresponded to the anterior commissure, while the posterolateral walls formed the optic nerves and chiasm. The pituitary gland was located on the posterior wall. Craniometric analysis revealed characteristic changes indicative of a concomitant dysmorphism. Discussion. The cause of encephalocele may be a failure of the closure of the primary neuropore, which requires further investigation. Unlike other types of encephalocele, patients with this condition often have bilateral nasal breathing problems, and a high incidence of associated malformations. The findings from our study are consistent with the literature [1]. Conclusion. The structure of the encephalocele is represented by the bulging of the anterior sections of the third ventricle (the region of the terminal plate). Functionally important structures, such as the chiasm, cerebral vessels and the bottom of the III ventricle, were located in the upper sections of the encephalocele, which makes it possible to consider the possibility of gentle surgical treatment in the volume of reduction of the hernial sac. However, difficulties in visualizing the pituitary gland have been identified, and these should be taken into account when planning surgery due to the risk of damage to this important structure.