Page 69 - Advanced concepts in orbital wall fractures

Introduction
Innovative surgical devices and diagnostic equipment for orbital wall
fractures, such as surgical navigation or endoscopy, are extensively used
in clinical practice1-5. The success rates of these modalities vary, yet they all
aim at improving the visualisation of the fracture and the predictability of
implant placement6-8. Combined fractures of the orbital floor and medial
wall in particular present a reconstructive challenge due to the anatomy
of the orbit. Postoperative complications occur due to suboptimal orbital reconstruction9-11. Preoperative virtual planning, as part of computer-
assisted surgery (CAS), is thought to be a valuable addition on its own in
achieving a pretraumatic anatomical reconstruction. C
The focus of CAS is on improving accuracy, usability, and possible shortening 4 of operation time8,12,13. It is used for several purposes, ranging from trauma
treatment to orthognathic surgery and pathological resections14-16. CAS can
be divided into four steps: 1. advanced diagnostics, 2. preoperative virtual
planning (including designing patient-specific implants), 3. intraoperative navigation, and 4. intraoperative and postoperative evaluation. Due to the cost, availability, and technical support, the complete workflow of CAS is limited to well-equipped centres and primarily used for complex cases. Since software becomes more easily available, the first two steps become more accessible and relatively affordable for smaller clinics.
In the current literature on CAS, the focus is on the outcome of the complete process17-19. The outcome is the sum of the contributions of all four steps. The question remains as to which steps are more crucial and contribute most to the outcome. If the advanced diagnostics and virtual planning steps are crucial in increasing accuracy and reliability, then the more time-consuming, expensive, and technical step of navigation- assisted surgery may be discarded in some cases.
The aim of this study was to measure the additional value of three- dimensional preoperative virtual diagnostics and planning and evaluate the effects on implant position in orbital floor and medial wall fractures. To our knowledge, the preoperative steps (advanced diagnostics and
Preoperative planning
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