Acrylic cranioplasty with alginate molding: technical note.

OBJECTIVE: Acrylic cranioplasty for cranial defects is a common neurosurgical procedure that is performed when the original bone flap becomes infected or is unusable for other reasons. We developed a simple technique to produce a complete copy of the original bone flap from acrylic, using alginate impression material as a mold.
METHODS: Alginate impression material was used to form a mold of the patient's original bone flap. Methylmethacrylate was then placed inside the mold to create an exact duplicate of the bone flap. The acrylic flap was sterilized with gamma irradiation and used for cranioplasty. Two patients who had cranial defects secondary to infections of their craniotomy bone flaps underwent cranioplasty with this technique. RESULTS AND
CONCLUSION: A perfect copy of the patient's original bone flap was easily and quickly created with this technique, and excellent cosmetic results were obtained. Operative time was shortened because the prosthesis was preformed before the operation. This technique can also be used to mold large or complex cranial defects as long as the original bone flap is available and there is no major cranial remodeling around the defect.