Chiari malformations in children: An overview

Figure 1 Chiari type 1 and associated holocord syringomyelia.

Figure 2 Chiari type 2 is characterized by a herniation of the tonsils, brainstem, vermis and also by corpus callosum agenesia, vermian agenesia, small posterior fossa, hydrocephalus and many other malformation of the central nervous system. The arrow indicates a low-lying torcular, which impeded a wide occipital craniectomy at surgery.

Figure 3 Basilar invagination associated to Chiari type 1. In these cases, surgical treatment must take into account, beyond a craniocervical decompression, also a craniocervical fixation.

Figure 4 Chiari type 1 associated to a syndromic craniosynostosis (Pfeiffer syndrome). There is also severe hydrocephalus, related to an intracranial venous hypertension.

Figure 5 Two cases of syringomyelia caused by Chiari type 1 and limited to a limited segment of the spinal cord. A and B: Cerebellar signs and symptoms are not present in Chiari type 1, since no eloquent neurological functions are located in the tonsils.

Figure 6 Hydromyelia, which indicated just a mild dilatation of the central spinal canal.

Figure 7 Mild or severe forms of scoliosis can be often found in Chiari malformations.

Figure 8 A case of successfully treated Chiari type 1 with craniocervical decompression. A: A large syringomyelia before surgery; B: A large syringomyelia disappeared after the craniocervical decompression.

Figure 9 Another case of successful treatment of Chiari type 1 with craniocervical decompression. A: The syringomyelia in the cervical spinal cord; B: A procedure that results in cervical spinal cord syringomyelia.

Figure 10  Two cases of craniocervical decompression. A and B: There is a dural patch implanted in both cases. This allows an enlargement of the diameter of the dural sac at the craniocervical junction and consequently a larger space for cerebrospinal fluid circulation and rhomboencephalic structures.

Figure 11  Images show a pseudomeningocele, caused by a leak of cerebrospinal fluid in the epidural space. A and B: The most common complications include injury to the vascular and neural structures, pseudomeningocele. This is a frequent complication of craniocervcal decompression.