The histology of bone and dura mater following cranial reconstruction in a rabbit model

Cranioplasty following skull base surgery is considered the standard of care. Postoperative difficulties such as cerebrospinal leak, aseptic meningitis and headache may be related to substances used in reconstruction. Substances commonly used in cranial reconstruction such as; adipose tissue, muscle, and methyl methacrylate are associated with a significant inflammatory response. Hydroxyapatite cement (BoneSource, Leibinger) has recently received PDA approval for use in humans. Initial reports show good biocompatability but information concerning its interaction with the dura mater is lacking. Data regarding osseointegration in humans is not available. A rabbit model for cranioplasty was used to compare methyl methacrylate, adipose tissue, titanium mesh, muscle and hydroxyapatite cement. Histopathologic analysis was performed twelve weeks after reconstruction. Each material was analyzed for inflammation, fibrosis, foreign body reaction and osseointegration. Hydroxyapatite as compared to the other reconstruction modalities showed good osseointegration with no inflammatory response. Radiographie analysis of cranial reconstruction has been performed to determine the degree of osseointegration.