OP060: Virtual 3D maxillary tumor marking – Exact intraoperative coordinate mapping improve post-operative radiotherapy – Technology, principal consideration and clinical implementation

Abstract

Background The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient’s specific tumor information (invasion to vessels and nerves, non-resectable tumor) to oncologists, radiotherapists and pathologists. Aim The purpose of this work was to develop, establish and clinically evaluate a novel, user-friendly, language independent and multidisciplinary tool to provide intraoperative collected data to the surgeon, oncologist, radiotherapist, pathologist and radiologist. Methods 19 Patients where operated with the support of computer assisted surgery. Time needed for preoperative planning including data transfer, dataset alignment, automatic and manual object segmentation, trajectories and additional safety checkups was measured in minutes. Accuracy of our set-up was recorded after registration. Finaly surgical time and Quality improvements were evaluated by comparison of hard and soft-tissue and the deviation of the correct position of the preplaned implants with the postoperative results was compared. Results Successful preoperative planning, import of image data suitable for navigation and intraoperative precise infrared-based navigation was obtained for all patients without any complications. The registration of patient data at the navigation system using screws as fiducial markers delivered a navigation accuracy with a mean deviation of 1.3 ± 0.6 mm in our cases. The novel method of intra-operative marking of specimen either frozen sections or surgical margins eases the storage and further use of intra-operative information. Image-guided navigation technique for head and neck oncologic surgery provides a precise, safe surgical method with real time excellent anatomic orientation. Conclusion Regarding the advantages of computer-assisted surgery, this technique will play a major part in craniofacial reconstructive surgery and will address widespread general methodological solutions that are of great interest in multidisciplinary oncologic treatment.