Ependymoma Dedifferentiated

"Differentiated ependymoma": description of the pathology

Ependymomas belong to a group of tumors of the central nervous system (CNS) that arise from glial cells or ependyma (vascular endothelium). They are characterized by slow growth, usually occur in the third decade of life, and rarely metastasize. Classically, ependymoid tumors are benign, but rarely can

Ependymomas are tumors mainly of ependyma (cells that form the wall ventricles of the spinal cord and brain), growing both expansively and infiltratively in the brain or spinal cord. Ependymoblastoma (intracerebral mature) and schwannomas (the most common neuroma of the basilar part of the auditory nerve) are not as widespread. However, depending on the location, complications may arise due to the spread of the process to the cranial nerves. These lesions are the result of the direct impact of tumor tissue on the sensory organs.

Clinically: ependymoma is usually detected in the third or fourth decade of life. The topography of the tumor is usually limited to the middle and lateral parts of the third ventricle. The clinical picture is dominated by symptoms associated with impaired circulation of cerebrospinal fluid.

Diagnosis: X-ray of the skull in the lateral projection reveals ovoid darkening of the hemisphere adjacent to the tumor with displacement of the median structures; Contrast enhancement reveals a clear boundary between the tumor, which displaces adjacent structures, and the membranes. Computed tomography scans help in diagnosis. If the tumor compresses the optic nerve, a decrease in visual acuity is determined in one eye (usually on the affected side). The appearance of bilateral paretic strabismus is caused by compression of the corresponding nerves. In the fundus, swelling of the papillary membrane and hemorrhages are detected. The development of spontaneous nystagmus is characteristic of the meningoradicomyelolytic type of tumors; if the cerebral component is involved in the formation of hydrocephalic syndrome, horizontal nystagmus is determined. When the tumor is located caudally, Venel syndrome or Todd-Lacuesta syndrome develops. Clinical diagnosis becomes more reliable after neuroimaging studies. MRI and CT largely complement each other, making it possible to differentiate ependymoma from other space-occupying formations of the third ventricle; MRI examination allows solving issues of differential diagnosis.

Treatment is surgical. The radical method is removal of the tumor with wedge-shaped resection of the skull bones and cranioplasty surgery. Removal of both intraventricular and subdural tumors to ensure complete removal is especially important in dedifferentiated ependymomas. In the case of ependymomas of the anterior horn (resectable volume), osteoplastic craniopharyngioplasty is indicated, accompanied by removal of the medial parts of the frontal lobes in the area of ​​the interhemispheric fissure. In case of severe disturbances in liquorodynamics, it is necessary to simultaneously perform decompressive trepanation of the bottom of the third ventricle, and if the lateral part of the third ventricle is damaged, plastic surgery of its lateral walls is performed. Sometimes it is necessary to begin the operation immediately without additional preoperative examination, which is necessary in case of severe clinical manifestations. After surgery, two-stage treatment is performed. Usually, to relieve ventriculoperitoneal complications, they resort to intragastric installation of shunt systems that provide connection to the lateral stomachs.