A Novel System for Navigation-and Robot-Assisted Craniofacial Surgery: Establishment of the Principle Prototype.

PURPOSE: The authors aimed to develop 1 novel navigation-guided robotic system for craniofacial surgery to improve accuracy during operation. MATERIALS AND METHODS: A new 7-DOF (7-degree-of-freedom) robotic arm was designed and manufactured. Based on our self-developed navigation system TBNAVIS-CMFS, the key technique of integration was studied. A phantom skull model was manufactured based on computed tomography image data and used for the preexperimental study. Firstly, virtual planning was achieved through the TBNAVIS-CMFS, where the Le Fort I procedure was executed through simulation. Then, the actual Le Fort 1 osteotomy was expected to perform with the use of the robotic arm following the instructions from the navigation system. RESULTS: The theoretical prototype of navigation-guided robotic system for craniofacial surgery was established successfully, which performed the planned Le Fort I procedure with the whole process visible on the screen. CONCLUSIONS: The technical method of navigation-guided robotics system, allowing the operator to practice the virtual planning procedure through navigation system as well as perform the actual operation thru the robotic arm, could be regarded as a valuable option for benefiting craniofacial surgeons.

Navigation-guided lateral gap arthroplasty as the treatment of temporomandibular joint ankylosis.

PURPOSE: This article presents a novel method of navigation-guided lateral gap arthroplasty (LGA) in the treatment of temporomandibular joint ankylosis (TMJA). MATERIALS AND METHODS: Six patients with unilateral TMJA from 2007 through 2011 were included in this study. Presurgical planning was performed to determine the amount and extent of ankylosed bone to be resected using the simulation platform. Minimum follow-up was 6 months. Patients were monitored for complications and signs of recurrence. Maximum mouth opening (MO) was measured and compared intra- and postoperatively. RESULTS: Preoperative planning was performed at the STN or Accu-Navi workstation. The amount and extent of ankylosed bone to be resected was determined. All 6 LGAs were completed successfully using real-time instrument- and pointer-based navigation. Measurements performed intraoperatively showed that the mean for maximum MO was about 35 to 40 mm and remained the same postoperatively. Follow-up evaluation showed remarkable improvement in function and esthetics, with no signs of recurrence. CONCLUSION: Navigation-guided LGA can be regarded a viable option for performing this delicate and complicated surgical procedure.

Image-guided surgical navigation for removal of foreign bodies in the deep maxillofacial region.

PURPOSE: Most trauma surgeons encounter numerous penetrating injuries. Some foreign bodies can cause pain, infection, and discomfort to the patient. Serious functional disorders also are likely to occur. Foreign bodies in critical areas must be removed. This report describes the use of image-guided technology for the removal of foreign bodies deep in the maxillofacial region. PATIENTS AND METHODS: From 2008 through 2011, 5 patients with foreign bodies in the maxillofacial area underwent image-guided removal at the authors' department. The STN navigation system (Stryker-Leibinger, Freiburg, Germany) was used for surgical planning and intraoperative navigation. Preoperatively, computerized tomography and digital subtraction angiography were used to create 3-dimensional views of the region to aid surgeons in more accurately defining the spatial location of the foreign object. During surgery, the foreign objects and surgical instruments were visualized on the screen. RESULTS: In all 5 cases, the foreign bodies were removed by minimally invasive access without any complications. Surgical time was approximately 40% shorter compared with the conventional technique of not using image-guided navigation. A 1-year postoperative evaluation showed that the patients' complaints and symptoms had resolved, function was restored, and esthetics were remarkably improved. CONCLUSION: Navigation-guided removal of foreign bodies in the complex, deep maxillofacial region in proximity to vital areas can be regarded an ideal and valuable option for these potentially complicated procedures.

Real-time image-guided recontouring in the management of craniofacial fibrous dysplasia.

OBJECTIVE: This report presents our experience using computer-aided recontouring in the surgical management of complex craniofacial fibrous dysplasia with the use of a navigation system developed by the authors. STUDY DESIGN: A total of 21 patients (9 men and 12 women) with craniofacial fibrous dysplasia and mean age of 23 years (range, 17-32 years) were included in this study from 2007 to 2012. By creating a mirror image of the unaffected side on the affected side as a virtual treatment template, we completed the recontouring procedures in real time with the aid of the navigation system that we developed (Accu-Navi). The surgical outcome was assessed by superimposing the postoperative computed tomography (CT) images onto the preoperative CT images. RESULTS: The precise preoperative simulation and intraoperative navigation enabled the surgeon to complete the recontouring procedure visually. Postoperative CT was compared with the preoperative plan, yielding an average discrepancy of <1.0 mm. Postoperative follow-up found that both facial aesthetics and patient satisfaction improved remarkably. CONCLUSIONS: Navigation-guided recontouring shows benefits in improving accuracy and safety for this complicated procedure.