Accuracy of the computer-aided surgical simulation (CASS) system in the treatment of patients with complex craniomaxillofacial deformity: A pilot study.

PURPOSE Current surgical planning methods are usually not adequate for the treatment of patients with complex craniomaxillofacial (CMF) deformities. To this end, we have developed a 3-dimensional (3D) computer-aided surgical simulation (CASS) planning method for the treatment of patients with complex CMF deformities. The purpose of this pilot study was to evaluate the accuracy of this technique in the treatment of patients with complex CMF deformities. PATIENTS AND METHODS Five patients with complex CMF deformities were enrolled. Surgeries were planned with the CASS planning method. Surgical plans were transferred to patients at the time of surgery via computer-generated splints. After surgery, outcome evaluation was completed by first superimposing the postoperative computed tomography (CT) model onto the planned model, and then measuring the differences between planned and actual outcomes. The criteria used to determine the accuracy of the technique were as follows: a linear difference between planned and actual outcomes of less than 2 mm, and an angular difference of less than 4 degrees . RESULTS All patients underwent surgery as planned. With the use of CASS planning, medians of the differences between planned and actual postoperative outcomes were limited to 0.9 mm and 1.7 degrees . CONCLUSION The results of this pilot study are promising. They will be used as the basis of calculations needed to determine the sample size for a larger and more comprehensive study that will be undertaken to assess the accuracy of CASS planning methods.