Hydrogel-induced cervicomedullary compression after posterior fossa decompression for Chiari malformation. Case report.

The use of an absorbable hydrogel dural sealant has been approved for neurosurgical applications with no published reports of complications to date. The authors present the case of a 13-year-old girl with syringomyelia and quadriparesis who underwent posterior fossa decompression and dural augmentation for Chiari malformation Type I. Dural closure was performed with a dural substitute patch, hydrogel dural sealant, and gelatin sponge. Magnetic resonance imaging, performed after initial postoperative improvement in the patient's quadriparesis deteriorated, demonstrated an expanding epidural mass collection causing cervicomedullary compression. Exploration on postoperative Day 15 revealed an expanded layer of hydrogel underlying a layer of gelatin sponge. The authors conclude that hydrogel dural sealants should be used cautiously in spaces that cannot tolerate significant mass effect.