Anatomical variants of Arnold – Chiari type II malformation and methods of surgical interventions

The formation of hydrocephalus in Arnold – Chiari type II anomaly has an obstruction mechanism, which consists in disconnecting the cerebrospinal fluid system of the brain and the cerebrospinal fluid space, turning off the damper function. Having considered the pathogenetic foundations and anatomical variants of the relationship between the structures of the posterior cranial fossa, it was revealed that endoscopic third ventriclostomy does not restore the communication of two liquor compartments and, as a result, cannot be a method of treating hydrocephalus in this pathology. Decompression of the posterior cranial fossa has extremely limited use. Ventriculo-peritoneal shunting is a universal and effective method of treating hydrocephalus in Arnold-Chiari type II malformation. Intrauterine correction myelomeningocele is the only method of preventing hydrocephalus in children with open forms of spinal dysraphism.

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