Resolution of tension pseudomeningocele complicating foramen magnum decompression for Chiari I malformation after ventriculoperitoneal shunt: A case report

Int J Surg Case Rep. 2025 Jun 20:133:111510. doi: 10.1016/j.ijscr.2025.111510. Online ahead of print.

Abstract

Introduction: Tension pseudomeningocele is a rare complication that arose after foramen magnum decompression in a patient with Chiari I malformation and syringomyelia. This article presents a case that was effectively managed through cerebrospinal fluid diversion methods, highlighting the mechanisms involved and the treatment option used.

Case report: A 15-year-old girl came to our clinic with allodynia in the right anterior chest wall that had lasted for six months. An MRI showed a type 1 Chiari malformation along with syringomyelia from C2 to C6. After performing foramen magnum decompression and duraplasty, there was an improvement in the syringomyelia; however, the patient developed a tension pseudomeningocele in the posterior fossa. She then had a ventriculoperitoneal shunt placed, which successfully resolved the tension pseudomeningocele and the cerebrospinal fluid leakage.

Discussion: Pseudomeningocele is a significant postoperative complication that can occur following foramen magnum decompression, potentially worsening neurological outcomes through mechanisms such as cord edema and the progression of syringomyelia. This condition may arise from a sustained craniospinal pressure gradient at the foramen magnum, which promotes the accumulation of cerebrospinal fluid within the pseudomeningocele cavity. As a result, cerebrospinal fluid diversion techniques, such as pseudomeningocele-peritoneal shunts or ventriculoperitoneal shunts, may be employed to reduce pressure within the cavity and restore balance to the craniospinal pressure gradient, thereby enhancing the patient's clinical status.

Conclusion: The implementation of cerebrospinal fluid diversion procedures may be pivotal in addressing tension pseudomeningocele in patients with Chiari I malformation.

Keywords: Chiari I malformation; Foramen magnum decompression; Hydrocephalus; Pseudomeningocele; Ventriculo-peritoneal shunt.

Publication types

  • Case Reports