Sterile Inflammatory Response Mimicking Infection after DuraGen Duraplasty: A Case Report.

DuraGen, a collagen matrix-based artificial dura mater, is widely used in neurosurgery because of its biocompatibility and ease of use. Although generally considered safe, we present a rare case of a foreign body reaction to DuraGen presenting as a sterile inflammatory response. A 40-year-old woman underwent total resection of a right convexity meningioma, with dural repair using DuraGen. On postoperative day 31, she developed headache, nausea, and vomiting. Imaging revealed significant cerebral edema around the surgical cavity with midline shift but no signs of infection on diffusion-weighted imaging. To rule out infection, reoperation was performed. Intraoperatively, there was no purulence or necrosis, but DuraGen was found adherent to the cortical surface. The artificial dura was removed and replaced with Gore-Tex. Microbiological cultures were negative. Histopathology showed inflammatory granulation tissue with eosinophilic infiltration, indicating a foreign body reaction. The patient's symptoms resolved immediately after surgery, and follow-up imaging at 5 months confirmed complete radiological resolution. This case highlights a rare but significant complication of DuraGen, demonstrating that foreign body reactions can mimic infectious processes and lead to severe cerebral edema and intracranial hypertension. Awareness of this potential complication is important for neurosurgeons, especially when infection is suspected but not clearly supported by imaging or intraoperative findings. Timely recognition and removal of the offending material can lead to rapid clinical and radiological improvement. This case underscores the importance of considering foreign body reaction in the differential diagnosis of delayed deterioration after duraplasty, particularly when infection is not definitively confirmed.