"Demineralized Bone Matrix and Resorbable Mesh Bilaminate Cranioplasty is Ineffective for Secondary Reconstruction of Large Pediatric Cranial Defects".

Replacement of the autologous bone flap after decompressive craniectomy can be complicated by significant osteolysis or infection with large defects over scarred dura. Demineralized bone matrix (DBM) is an alternative to autologous reconstruction, effective when reconstructing large defects using a resorbable mesh bilaminate technique in primary cranioplasty, but this technique has not been studied for revision cranioplasty and the setting of scarred dura.Retrospective review was performed of patients receiving DBM and resorbable mesh bilaminate (DRMB) cranioplasty for post-decompressive craniectomy defects. Seven patients (mean age 4.2 years) were identified with mean follow up of 4.0 years. Computed tomography before the DRMB cranioplasty and at least one year postoperative were compared. Defects were characterized and need for revision were assessed.All patients had craniectomy with associated hemi-dural scarring. Five patients had autologous bone flap cranioplasty associated with near-total osteolysis and two patients had deferral of bone flap prior to DRMB cranioplasty. DRMB cranioplasty demonstrated unpredictable and poor ossification with bony coverage unchanged at post-operative follow-up. All patients required major revision cranioplasty at mean time 2.5 years. Porous polyethylene was successfully utilized in six of the revisions while exchange cranioplasty was used in the remaining patient, with mean follow up of 1.4 years.Although DBM and resorbable mesh bilaminate is appropriate for primary cranioplasty, it should be avoided in the setting of scarred or infected dura in favor of synthetic materials or exchange cranioplasty.