[Cranioplasty using cryopreserved autogenous bone]

Various materials and methods can be used for cranioplasty following external decompression craniotomy. We generally use cryopreserved autogenous bone for cranioplasty following external decompression. We assessed several factors, including histological changes in the stored bone, postoperative skull X-ray changes, postoperative changes in skull morphology, and the incidence of postoperative infections. The purpose of this study was determined if our materials and preservation methods were appropriate. The subjects were 110 patients who underwent cranioplasty using cryopreserved autogenous bone following external decompression at our hospital. They were followed up for at least one year. Bone fragments removed at the time of external decompression were stored at -40 degrees C an ultra-low temperature freezer and returned to room temperature before using them for cranioplasty. Follow-up skull x-ray films were obtained for 1-10 years postoperatively. Almost all of the 46 patients showed bone union at least one year after cranioplasty, but seven patients (15%) had marked bone resorption and bone atrophy after 3 years or longer. Five of these patients had a concomitant ventriculo-peritoneal shunt. Two of them developed collapse of the skull due to bone resorption, and this was considered to have been influenced by the shunt. Epidural empyema occurred postoperatively in five patients (4.5%), and staphylococci were the causative organisms in all five cases. The infections were completely cured by removal of the bone graft, debridement of the wound, and epidural drainage. Cranioplasty following external decompression craniotomy using cryopreserved autogenous bone fragments is a simple procedure, and the materials are inexpensive. Many of our patients who underwent cranioplasty using cryopreserved autogenous bone experienced no serious complications.(ABSTRACT TRUNCATED AT 250 WORDS)