Automatic segmentation and user-friendly software techniques for virtual surgical planning of mandibular reconstruction.

Compared to conventional mandibular reconstruction surgery, a recent approach of virtual planning can reduce surgical time providing reliable surgical outcomes. We present our virtual surgical planning software using automatic segmentation and user-friendly techniques. Evaluation experiments compared with a commercial software prove that the proposed software can achieve successful surgical planning in reduced time with reliable accuracy.

Three-Dimensional Evaluation of Similarity of Right and Left Knee Joints

PURPOSE: The purpose of this study was to evaluate the anatomical similarity of three-dimensional (3D) morphometric parameters between right and left knees. MATERIALS AND METHODS: Ten fresh-frozen paired cadaveric knees were tested. Following dissection, footprint areas of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were measured. Surface scanning was performed using a 3D scanner. Scanned data were reproduced and morphometric parameters were measured on specialized software. After making mirror models, we compared footprint center positions of the ACL and PCL of both sides and calculated the average deviation of 3D alignment between the right- and left-side models. RESULTS: No significant side-to-side differences were found in any morphometric parameters. Bony shapes displayed a side-to-side difference of < 1 mm. Distal femoral and proximal tibial volumes did not present side-to-side differences, either; the average 3D deviations of alignment between the right and left sides were 0.8±0.4/1.1±0.6 mm (distal femur/proximal tibia). Center-to-center distances between the right and left ACL footprints were 2.6/2.7 mm (femur/tibia) for the anteromedial bundle and 2.4/2.8 mm for the posterolateral bundle. They were 1.9/1.5 mm for the anterolateral bundle and 2.2/1.8 mm for the posteromedial bundle of the PCL. CONCLUSIONS: There was a remarkable 3D morphometric similarity between right and left knees. Our results might support the concept of obtaining morphologic reference data from the uninvolved contralateral knee.