Virtual Planning and Intraoperative Navigation in Craniomaxillofacial Surgery

Surgery planning assisted by computer represents one important example of the collaboration between surgeons and engineers. Virtual planning allows surgeons to pre-do the surgery by working over a virtual 3D model of the patient obtained through a computer tomography. Through surgical navigation, surgeons are helped while working with deep structures and can check if they are following accurately the surgical plan. These assistive tools are crucial in the field of facial reconstructive surgery. This paper describes two cases, one related to orbital fractures and another one related to oncological patients, showing the advantages that these tools provide, specifically when used for craniomaxillofacial surgery

Virtual Surgical Planning in Craniomaxillofacial surgery: A Structured Review

Craniomaxillofacial (CMF) surgery is a challenging and very demanding field that involves the treatment of congenital and acquired conditions of the face and head. Due to the complexity of the head and facial region, various tools and techniques were developed and utilized to aid surgical procedures and optimize results. Virtual Surgical Planning (VSP) has revolutionized the way craniomaxillofacial surgeries are planned and executed. It uses 3D imaging computer software to visualize and simulate a surgical procedure. Numerous studies were published on the usage of VSP in craniomaxillofacial surgery. However, the researchers found inconsistency in the previous literature which prompted the development of this review. This paper aims to provide a comprehensive review of the findings of the studies by conducting an integrated approach to synthesize the literature related to the use of VSP in craniomaxillofacial surgery. Twenty-nine related articles were selected as a sample and synthesized thoroughly. These papers were grouped assigning to the four subdisciplines of craniomaxillofacial surgery: orthognathic surgery, reconstructive surgery, trauma surgery and implant surgery. The following variables – treatment time, the accuracy of VSP, clinical outcome, cost, and cost-effectiveness – were also examined. Results revealed that VSP offers advantages in craniomaxillofacial surgery over the traditional method in terms of duration, predictability and clinical outcomes. However, the cost aspect was not discussed in most papers. This structured literature review will thus provide current findings and trends and recommendations for future research on the usage of VSP in craniomaxillofacial surgery

Virtual 3D tumor marking-exact intraoperative coordinate mapping improve post-operative radiotherapy

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

Radiological Society of North America (RSNA) 3D printing Special Interest Group (SIG): Guidelines for medical 3D printing and appropriateness for clinical scenarios

Este número da revista Cadernos de Estudos Sociais estava em organização quando fomos colhidos pela morte do sociólogo Ernesto Laclau. Seu falecimento em 13 de abril de 2014 surpreendeu a todos, e particularmente ao editor Joanildo Burity, que foi seu orientando de doutorado na University of Essex, Inglaterra, e que recentemente o trouxe à Fundação Joaquim Nabuco para uma palestra, permitindo que muitos pudessem dialogar com um dos grandes intelectuais latinoamericanos contemporâneos. Assim, buscamos fazer uma homenagem ao sociólogo argentino publicando uma entrevista inédita concedida durante a sua passagem pelo Recife, em 2013, encerrando essa revista com uma sessão especial sobre a sua trajetória

Facial Reconstruction: A Systematic Review of Current Image Acquisition and Processing Techniques

Plastic and reconstructive surgery is based on a culmination of technological advances, diverse techniques, creative adaptations and strategic planning. 3D imaging is a modality that encompasses several of these criteria while encouraging the others. Imaging techniques used in facial imaging come in many different modalities and sub-modalities which is imperative for such a complex area of the body; there is a clear clinical need for hyper-specialized practice. However, with this complexity comes variability and thus there will always be an element of bias in the choices made for imaging techniques

Navigation-guided osteotomies improve margin delineation in tumors involving the sinonasal area: A preclinical study

Objectives: To demonstrate and quantify, in a preclinical setting, the benefit of three-dimensional (3D) navigation guidance for margin delineation during ablative open surgery for advanced sinonasal cancer. Materials and methods: Seven tumor models were created. 3D images were acquired with cone beam computed tomography, and 3D tumor segmentations were contoured. Eight surgeons with variable experience were recruited for the simulation of osteotomies. Three simulations were performed: 1) Unguided, 2) Guided using real-time tool tracking with 3D tumor segmentation (tumor-guided), and 3) Guided by 3D visualization of both the tumor and 1-cm margin segmentations (margin-guided). Analysis of cutting planes was performed and distance from the tumor surface was classified as follows: “intratumoral” when 0 mm or negative, “close” when greater than 0 mm and less than or equal to 5 mm, “adequate” when greater than 5 mm and less than or equal to 15 mm, and “excessive” over 15 mm. The three techniques (unguided, tumor-guided, margin-guided) were statistically compared. Results: The use of 3D navigation for margin delineation significantly improved control of margins: unguided cuts had 18.1% intratumoral cuts compared to 0% intratumoral cuts with 3D navigation (p < 0.0001). Conclusion: This preclinical study has demonstrated the significant benefit of navigation-guided osteotomies for sinonasal tumors. Translation into the clinical setting – with rigorous assessment of oncological outcomes – would be the proposed next step

Vergleich der präoperativen Planung mit dem postoperativen Ergebnis bei computergestützt geplanten posttraumatischen Rekonstruktionen des Mittelgesichts

Das Ziel der Arbeit ist die postoperative Implantat- und Knochensegmentposition mit der präoperativ geplanten virtuellen Position bei sekundären Rekonstruktionen des Mittelgesichtsskeletts und primären Rekonstruktionen der Orbitawände ohne Verwendung von Navigationssystemen zu vergleichen. Die erste Studie wertet die Implementierung der VSP zur sekundären Korrektur von posttraumatischen Deformitäten im Bereich des lateralen und zentralen Mittelgesichts (des Jochbeines, Jochbogens und Oberkiefers) aus. Die zweite Studie untersucht die Implementierung der VSP zur primären Rekonstruktion der inferioren und medialen Orbitawände. Die Patientenkohorte in der ersten Studie besteht aus Patienten, die von 2013 bis 2019 in der Klinik für Mund-, Kiefer- und Gesichtschirurgie der LMU München wegen zuvor nicht adäquat versorgter Frakturen im zentralen und lateralen Mittelgesichtsbereich operativ behandelt wurden. Patienten mit isolierten Orbitawand- oder Le Fort I-Frakturen wurden von der Studie ausgeschlossen. In der zweiten Studie wurden Patienten retrospektiv eingeschlossen, die von 2015 bis 2019 in der Klinik für Mund-, Kiefer- und Gesichtschirurgie der LMU München aufgrund von isolierten Orbitawandfrakturen operiert wurden. 8 Patienten wurden in die erste Studie und 27 Patienten in die zweite Studie aufgenommen. Die mediane Abweichung zwischen geplanter und definitiver Position für die PSI und die Knochensegmente wurde erstens zwischen den gesamten Modelloberflächen mittels einem geeigneten Algorithmus der Software 3-Matic und zweitens an anatomisch korrespondierenden Referenzpunkten ausgemessen, analysiert und ausgewertet. In der ersten Studie betrugen die medianen Abstände zwischen der virtuell geplanten und der postoperativen Position der PSI 2,01 mm (n = 18) gegenüber einem medianen Abstand bezüglich der Knochensegmente von 3,05 mm (n = 12). Bei Patienten, bei denen PSI verwendet wurden, war die mediane Verschiebung der Knochensegmente geringer als in der Gruppe mit vorgebogenen Platten. Darüber hinaus konnte der Jochbeinbereich mit geringerer Abweichung als der Oberkieferbereich positioniert werden. Ferner zeigte sich die Zahnbogenregion im Vergleich zur kranialen Oberkieferregion eine höhere Positionierungsgenauigkeit. In der zweiten Studie zeigten die Medianwerte für die Referenzpunktabmessungen eine größere Abweichung bei den Implantaten zur Versorgung der medialen Orbitawand, nämlich 0,79 mm. Der Wert für die Gruppe der Orbitabodenimplantate lag bei 0,45 mm. Es konnte keine Korrelation zwischen der postoperativen Diplopie und der Passgenauigkeit der Implantatposition nachgewiesen werden. Die vorliegende Arbeit zeigt erstens die Machbarkeit der Übertragung der VSP durch CAD/CAM Werkzeuge für die sekundäre Rekonstruktion komplexer posttraumatischer Restdeformitäten im Mittelgesicht, jedoch mit relativ erhöhter Ungenauigkeit, und zweitens die Möglichkeit einer genauen Umsetzung der Planungsposition bei der Rekonstruktion der inferioren und/oder medialen Orbitawand. Die in der ersten Studie beobachteten höheren Abweichungen lassen sich durch Unterschiede in der Bewertungsmethode sowie durch die Komplexität der Deformitäten, Osteotomien und chirurgischen Verfahren erklären, so dass der Einsatz von Navigationssystemen die Genauigkeit der Repositionierung weiter verbessern könnte