Three-dimensional imaging, surgical planning, and image-guided therapy

Three-dimensional imaging is now widely available and used often to aid in the comprehension and application of volumetric data to diagnosis, planning, and therapy. CAS comprises visualization of complex anatomy, planning of interventions, image-based guidance for diagnosis and therapy, evaluation of results, and follow up. CAS-networked workstations have interactive pointing devices and specialized software that support simulation, navigation, and follow-up functions. Volumetric and real time digital imaging are used to plan procedures, for intra-operative guidance, and to monitor progress. Monitoring with real time ultrasound, fluoroscopy, and MR imaging is performed to assess local effects of specific therapeutic modalities. Normative data bases, especially digital stereotactic atlases, allow incorporation of a priori anatomic knowledge in CAS. Computer-assisted planning and simulation of complex craniofacial surgery is feasible with commercially available software and hardware using CT scan and MR images. This can be performed by an operator with low-level computer skills on a graphics workstation. The outcome of computer-simulated surgery can be validated quantitatively. Computer-simulated surgery does affect the choice of intervention for patients with complex craniofacial anomalies. Further evaluation of the process is needed to determine the influence of surgical simulation and planning on outcome.