Repetitive subarachnoid hemorrhage caused by fracture of titanium mesh used in cranioplasty in the posterior cranial fossa: illustrative case.

Background: Cranioplasty is more than cosmetic repair for cranial defects; it is vital for patient rehabilitation after neurological injury. Despite its benefits, cranioplasty is associated with significant complications and requires careful planning. This report details the first reported case of subarachnoid hemorrhage (SAH) caused by failure and migration of titanium mesh used in suboccipital cranioplasty.

Observations: A 49-year-old male experienced recurrent SAH over 4 years, presenting every 2 years. Three years prior, the patient underwent suboccipital decompression craniotomy with titanium mesh implantation at another hospital. Imaging revealed mesh fracture with fragments migrating into the cervical spine at C3 and C4-5. The fractured edge of the mesh penetrated the dura and injured the cerebellar surface. A two-stage surgery removed the fractured mesh and migrated fragments successfully.

Lessons: Suboccipital cranioplasty using titanium mesh and involving the posterior margin of the foramen magnum is at risk of mechanical failure. Stress on the implanted titanium mesh from cervical movement can lead to metal fatigue and injury to the brain, nerves, and blood vessels. https://thejns.org/doi/10.3171/CASE24836.