Eosinophilic meningitis following suboccipital craniotomy without bovine dural graft: illustrative case

BACKGROUND: Eosinophilic meningitis is a rare known complication after brain surgery associated with duraplasty using artificial bovine graft. However, eosinophilic meningitis after craniotomy without bovine dural graft has not been reported. OBSERVATIONS: A 48-year-old female presented with lateral medullary infarction caused by a vertebral artery dissecting aneurysm incorporating the posterior inferior cerebellar artery (PICA). The authors performed occipital artery–PICA anastomosis and repaired the dura by primary suture without bovine graft. Thereafter, endovascular internal trapping using coils was conducted. Severe headache developed at postoperative day 17, and the patient was diagnosed with eosinophilic meningitis. After administration of a high-dose corticosteroid for 2 weeks, her symptoms and laboratory findings were improved. LESSONS: Postoperative eosinophilic meningitis is rarely related to craniotomy without using bovine graft. Neurosurgeons should consider the possibility of eosinophilic meningitis after craniotomy without a xenogeneic dural material.