P05.72 Single-step resection of spheno-orbital meningiomas and orbital reconstruction using customized CAD/CAM implants

Abstract

Computer-aided design and manufacturing (CAD/CAM) implants are fabricated based on volumetric analysis of computed tomography (CT) scans and are routinely used for the reconstruction of orbital fractures. We present three cases of patients with spheno-orbital meningiomas that underwent tumor resection, orbital decompression and orbital reconstruction with patient specific porous titanium or acrylic implants in a single procedure. The extent of bone resection of the spheno-orbital meningiomas was planned in a virtual three-dimensional (3D) environment using preoperative thin-layer CT data. The anatomy of the orbital wall in the resection area was reconstructed by superimposing the contralateral unaffected orbit and by using the information of the neighboring bony structures. The customized implants were designed in the desired size and shape using computer-aided manufacturing. Furthermore, a corresponding craniotomy template in the form of a frame was produced for precise craniotomy. All patients presented with a spheno-orbital meningioma and an exophthalmus. After osteoclastic craniotomy with the drilling template orbital decompression was performed. The cranioplasty implant fitted tightly in all three cases and could be easily fixated with mini-plates and screws, although in one case a reoperation was necessary for additional resection, as well as drilling and repositioning of the implant. The postoperative CT scans showed an accurate reconstruction of the orbital wall. After surgery, exophthalmos was substantially reduced and a satisfying cosmetic result was achieved in all patients. The concept of preoperative 3D virtual treatment planning and single-step orbital reconstruction with CAD/CAM-implants after tumor resection involving the orbit is well feasible and can lead to good cosmetic results.