One-stage Surgery for Malignant Skull and Scalp Tumor: Navigation-guided Tumor Resection and Cranioplasty Using Custom-made Implants: Technical Note.

One-stage tumor resection and cranioplasty for skull tumors using custom-made implants are beneficial for reducing patient burden, minimizing complications, and improving cosmetic outcomes. However, accurately determining the craniotomy line remains challenging. This technical note describes a method for integrating implant design data into a navigation system to facilitate accurate 1-stage surgery for skull and scalp tumors. Merged images of the implant design data and preoperative computed tomography scans were created. The craniotomy line was determined using a navigation system with merged images. After tumor resection, cranioplasty was performed using a custom-made implant. We applied this technique in 2 patients with metastatic skull tumors and 2 with primary scalp sarcomas with skull invasion. Gross total resection was achieved in all patients. The resection area was expanded beyond the preplanned margins in 2 cases because of tumor progression; the bone defects were filled or covered with bone cement or titanium plates, with positive cosmetic results. The alignment between the implants and skull was satisfactory, and no postoperative complications were observed. This technique enables accurate, efficient, and safe 1-stage surgery by ensuring precise osteotomy and optimal implant fitting in skull and scalp tumors.