Delayed pseudomyelomeningocele: a rare complication after foramen magnum decompression for Chiari malformation
Deniz Belen1, Uygur Er, Levent Gurses
1Ministry of Health, Diskapi Educational and Research Hospital Neurosurgery Department, Ankara 06110, Turkey. denizbelen2000@yahoo.com
Background:
A variety of complications after FMD with or without duraplasty for Chiari malformation have been described. Although cerebellar ptosis through the dural opening and pseudomeningocele are well-known rare complications of this procedure, spinal cord herniation manifesting as pseudomyelomeningocele formation has not previously been cited in the literature. In this report, we present a case of delayed pseudomyleomeningocele after FMD.
Case Description:
A 22-year-old man presented with progressive spinal cord compression symptoms 7 years after undergoing FMD for Chiari malformation. Craniocervical MRI of the patient revealed pseudomyelomeningocele at C1 level together with cord distortion. The patient underwent untethering surgery for spinal cord adhesions; neural tissue was freed microsurgically from the adjacent structures and duraplasty was performed with synthetic graft. In the early postoperative period, his symptoms resolved moderately.
Conclusion:
Neural tissue shift including the spinal cord through the dural opening may occur after a large posterior fossa decompression without duraplasty for Chiari malformation. Postoperative inadequate CSF circulation due to arachnoid scarring around the decompression area may facilitate this type condition. Early diagnosis of such a complication is of vital importance to prevent serious neurologic deficits, and release surgery with proper duraplasty and also restoration of CSF circulation is the choice of treatment.
Insights
A rare complication of Chiari malformation surgery, spinal cord herniation causing pseudomyelomeningocele, is presented. Early diagnosis and surgical release are crucial for preventing neurological deficits after posterior fossa decompression.
Area of Science:
- Neurosurgery
- Neurology
- Medical Case Reports
Background:
- Posterior fossa decompression (FMD) for Chiari malformation can lead to complications.
- Cerebellar ptosis and pseudomeningocele are known risks, but spinal cord herniation is a novel presentation.
Observation:
- A 22-year-old man developed delayed pseudomyelomeningocele 7 years post-FMD for Chiari malformation.
- Craniocervical MRI revealed pseudomyelomeningocele at C1 with spinal cord distortion.
Findings:
- The patient underwent successful untethering surgery with duraplasty, showing moderate symptom resolution.
- Spinal cord shift through the dural opening, potentially due to inadequate CSF circulation and arachnoid scarring, is implicated.
Implications:
- This case highlights spinal cord herniation as a previously undocumented complication of FMD.
- Prompt diagnosis and surgical intervention, including proper duraplasty and CSF circulation restoration, are vital for optimal patient outcomes.