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Microvascular Decompression: Salient Surgical Principles and Technical Nuances
Published on: July 5, 2011
Delayed tentorial herniation after crainoplasty with polymethylmethacrylate: a rare complication
Hitoshi Yamahata1, Hiroshi Tokimura, Jun-ichi Kuratsu
1Department of Neurosurgery, Faculty of Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshim-shi, Kagoshima 890-8520, Japan. yamahata-nsu@umin.net
Summary
A rare complication of polymethylmethacrylate cranioplasty, tentorial herniation, caused neurological symptoms five years post-surgery. Revision surgery with a ceramic implant resolved the patient's symptoms by relieving brain compression.
Area of Science:
- Neurosurgery
- Neurology
- Biomaterials
Background:
- Cranioplasty is a common procedure following craniectomy to restore skull integrity.
- Polymethylmethacrylate (PMMA) is a frequently used material for custom bone flaps in cranioplasty.
- Late complications of cranioplasty are uncommon but can significantly impact patient outcomes.
Observation:
- A 49-year-old male developed delayed neurological symptoms including diplopia and hemiparesis five years after PMMA cranioplasty.
- Magnetic resonance imaging (MRI) identified tentorial herniation without a distinct space-occupying lesion.
- The initial PMMA graft exhibited unevenness with inner surface protrusions causing cerebral compression.
Findings:
- Uneven PMMA cranioplasty can lead to delayed tentorial herniation and neurological deficits.
- Surgical revision with a ceramic implant successfully alleviated the patient's symptoms.
- Cerebrospinal fluid dynamics were likely restored upon release of compression from the initial graft.
Implications:
- Tentorial herniation is a previously undocumented late complication of PMMA cranioplasty.
- Careful contouring and material selection are crucial in cranioplasty to prevent delayed complications.
- This case highlights the importance of considering graft-related compression in late-onset neurological symptoms after cranioplasty.
