Cranioplasty using polymethyl methacrylate prostheses

In this retrospective Study we attempted to assess the clinical performance of prefabricated polymethyl methacrylate (PMMA) prostheses and to determine whether they Outperform intra-operatively moulded PMMA prostheses in reducing operating time, blood loss and surgical complications in elective delayed cranioplasty operations, after decompressive craniectomy, to repair large (> 100 cm(2)) cranial defects. Patients (n = 131) were divided into three groups according to the cranioplasty technique used. Group I patients received fresh frozen autograft bone that had been removed at the craniectomy and refrigerated at -80 degrees C. Group 2 included patients whose PMMA prosthesis was moulded intra-operatively. Group 3 patients received a custom-made prefabricated PMMA prosthesis manufactured using computer-aided design/computer-aided manufacturing (CAD/CAM). Group 2 patients required significantly more operating time than both group 1 (p < 0.001) and group 3 (p < 0.001) patients, but operating time did not differ significantly between groups I and 3 (p > 0.05). Mean intra-operative blood loss was significantly higher in group 2 than in group 1 (p = 0.015) but did not differ significantly between group I and group 3 (p > 0.05). The infection rate associated with prefabricated PMMA prostheses was lower than that for intra-operatively moulded PMMA prostheses and was comparable to that for autograft bone flaps. A CAD/CAM PMMA prosthesis is an excellent alternative when 110 autogenous bone graft harvested during craniectomy is available. (c) 2009 Elsevier Ltd. All rights reserved.