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Usefulness of an Osteotomy Template for Skull Tumorectomy and Simultaneous Skull Reconstruction
Tomito Oji1, Yoshiaki Sakamoto, Tomoru Miwa
1*Department of Plastic and Reconstructive Surgery †Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.
Background:
Simultaneous tumor resection and cranioplasty with hydroxyapatite osteosynthesis are sometimes necessary in patients of skull neoplasms or skull-invasive tumors. However, the disadvantage of simultaneous surgery is that mismatches often occur between the skull defect and the hydroxyapatite implant. To solve this problem, the authors developed a customized template for designing the craniotomy line.
Methods:
Before each operation, the craniotomy design was discussed with a neurosurgeon. Based on the discussion, 2 hydroxyapatite implants were customized for each patient on the basis of models prepared using computed tomography data. The first implant was an onlay template for the preoperative cranium, which was customized for designing the osteotomy line. The other implant was used for the skull defect. Using the template, the osteotomy line was drawn along the template edge, osteotomy was performed along this line, and the implant was placed in the skull defect.
Results:
This technique was performed in 3 patients. No implant or defect trimming was required in any patient, good cosmetic outcomes were noted in all patients, and no complications occurred.
Conclusion:
Use of predesigned hydroxyapatite templates for craniotomy during simultaneous skull tumor resection and cranioplasty has some clinical advantages: the precise craniotomy line can be designed, the implant and skull defect fit better and show effective osteoconduction, trimming of the implant or defect is minimized, and the operation time is shortened.

