In Situ Cranioplasty for Renal Cell Skull Metastasis: Technical Note

Treatment of a large, symptomatic skull metastasis requires surgical excision and in many cases postoperative radiation therapy. Immediate reconstruction of the skull for cerebral protection usually involves cranioplasty with titanium mesh and/or methyl methacrylate. Preoperative synthetic cranioplasty technology is yet to evolve sufficiently to allow computer-generated prostheses to precisely fit a defined craniectomy defect created at the time of tumor removal. We document the techniques used for simultaneous craniectomy and composite cranioplasty in the setting of a large occipital renal cell skull metastasis. Preoperative computed tomography (CT) and magnetic resonance (MR) imaging identified the pathological anatomy of an occipital skull metastasis presenting as an exophytic scalp mass. Preoperative angiography and embolization was performed followed by craniectomy in the semi-sitting position and composite cranioplasty using titanium mesh and methyl methacrylate. A series of steps in the surgical procedure are outlined to assist with safely and accurately performing the craniectomy and cranioplasty to guarantee the best surgical and cosmetic outcome. Postoperative CT imaging confirmed excellent contours of the cranioplasty. The method described herein allows for a single-step surgical procedure to excise a large skull metastasis and create a structurally sound and cosmetically acceptable composite cranioplasty. This method can also be used for the excision and repair of other skull tumors or anomalies requiring excision.