Preformed polymethylmethacrylate cranioplasties: report of 45 cases.

In 45 patients a preformed polymethylmethacrylate (PMMA) cranioplasty prosthesis was inserted. The cranial defects mainly were caused by trauma, removal of tumour and secondary infection of bone after intracranial operation. Several broken peroperatively cold-cured acrylic plates were replaced by preoperatively molded PMMA plates. The longest follow-up was seven years and the shortest four months; the average was 39 months. The size of the defect ranged from 6 cm2 to 175 cm2. The average age at operation was 33 years; the youngest patient was one year, the oldest 74 years. There were no acute postoperative complications. Two plates had to be removed nearly one year after insertion. Both patients had a long history of chronic bone infection before the PMMA cranioplasty was performed. The technical details will be described; the advantages of the method will be discussed.