A Virtual Surgical Planning Algorithm for Delayed Maxillomandibular Reconstruction.

Area of Science:

• Oral and Maxillofacial Surgery
• Biomedical Engineering
• Reconstructive Surgery

Background:

• Delayed maxillomandibular reconstruction often involves significant intraoperative uncertainty due to the absence of tumor specimens.
• Virtual surgical planning (VSP) recreates defects preoperatively, aiding surgeons in determining the size and shape of missing bony elements.
• Three VSP techniques are utilized: patient-specific modeling, contralateral mirroring, and scaled normative data.

Purpose of the Study:

• To develop and evaluate a hierarchical algorithm for virtual surgical planning in delayed maxillomandibular reconstructions.
• To assess the effectiveness and outcomes of different VSP techniques in complex reconstructive cases.

Main Methods:

• A retrospective analysis of delayed maxillomandibular VSP reconstructions performed between 2009 and 2016.
• Analysis of patient demographics, VSP modeling techniques (patient-specific, mirroring, normative data), and surgical characteristics.
• Evaluation of reconstructive outcomes and complications.

Main Results:

• Sixteen reconstructions were performed for osteoradionecrosis or oncologic defects, with most patients having prior surgery and radiation.
• Patient-specific modeling was most common (43.8%), followed by mirroring (37.5%) and normative data (18.8%).
• While normative and mirrored reconstructions aimed for anatomical restoration, patient-specific designs often required non-anatomical approaches; flap complications occurred in 12.5% of cases.

Conclusions:

• Virtual surgical planning offers significant advantages over traditional flap shaping in delayed reconstruction.
• An algorithmic VSP approach, utilizing available imaging and native anatomy, facilitates accurate planning and flap transfer.
• This method minimizes the need for intraoperative guesswork, leading to more predictable reconstructive outcomes.