Page 80 - Advanced concepts in orbital wall fractures

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Chapter 4
determined by a technician and the surgeons together. A deviation from this position does not necessarily mean that it leads to impaired clinical results. For instance, volume difference and possible entrapment of soft tissue are also believed to play an important role in clinical outcome. It is impossible to include these factors in this study. A perfect bony reconstruction does not imply a perfect clinical outcome as a great variety in soft tissues changes, such as fat atrophy, tissue dislocation, and scarring due to trauma and surgery, may occur29.
Numerous computer-assisted surgery systems are available. In this study, a single software program was used, which does not automatically imply similar results for all CAS systems. In our opinion and based on the study of Strong et al. most of the systems are comparable as they rely on merely the same principles30. There were small differences in outcome, but they were considered not clinically significant. New software is increasingly available, but should be used with caution until the accuracy of the software is confirmed.
Conclusion
The use of three-dimensional diagnostics and preoperative planning in orbital floor and medial wall fractures improves the predictability of implant positioning. They are important first steps in computer-assisted surgery, but they are also very useful on their own. Their use grants the surgeon the opportunity to analyse the size and fracture in comparison to several landmarks, to conduct volumetric analysis, and to mirror the unaffected side. Virtual surgery can be performed to determine implant size and position and can be used as a virtual guidance during surgery. Possible lack of intraoperative control can be dissolved by additionally using intraoperative navigation. Future research could focus on the combination of intraoperative imaging and preoperative planning.