Recurrence of symptoms after Chiari decompression and duraplasty with nonautologous graft material.

Nonautologous material is commonly used for dural grafting. Although good results have been reported with the use of some of these materials in cranial surgery, there is a paucity of information regarding their use in craniocervical decompressive surgery. We report three cases of patients with Chiari malformation type I who experienced recurrent or new-onset Chiari symptoms after surgical decompression and duraplasty with bovine pericardium, Gore-Tex or cadaveric dura. We review the use of these materials and propose possible mechanisms by which a reaction to a nonautologous graft could cause recurrent Chiari symptoms. The preferential use of autologous material for dural grafts during posterior fossa decompressive surgery should prevent this cause of symptom recurrence.