Scoping Zygomaticomaxillary Complex Fractures With the Eyes of Virtual Reality: Operative Protocol and Proposal of a Modernized Classification

Three-dimensional technologies in presurgical planning of bone surgeries: current evidence and future perspectives

BACKGROUND

The recent development of three-dimensional (3D) technologies introduces a novel set of opportunities to the medical field in general, and specifically to surgery. The preoperative phase has proven to be a critical factor in surgical success. Utilization of 3D technologies has the potential to improve preoperative planning and overall surgical outcomes. In this narrative review article, the authors describe existing clinical data pertaining to the current use of 3D printing, virtual reality, and augmented reality in the preoperative phase of bone surgery.

METHODS

The methodology included keyword-based literature search in PubMed and Google Scholar for original articles published between 2014 and 2022. After excluding studies performed in nonbone surgery disciplines, data from 61 studies of five different surgical disciplines were processed to be included in this narrative review.

RESULTS

Among the mentioned technologies, 3D printing is currently the most advanced in terms of clinical use, predominantly creating anatomical models and patient-specific instruments that provide high-quality operative preparation. Virtual reality allows to set a surgical plan and to further simulate the procedure via a 2D screen or head mounted display. Augmented reality is found to be useful for surgical simulation upon 3D printed anatomical models or virtual phantoms.

CONCLUSIONS

Overall, 3D technologies are gradually becoming an integral part of a surgeon's preoperative toolbox, allowing for increased surgical accuracy and reduction of operation time, mainly in complex and unique surgical cases. This may eventually lead to improved surgical outcomes, thereby optimizing the personalized surgical approach.

Contemporary management of complex craniofacial trauma: virtual planning, navigation and the novel thermoformed cage splints in a strategic, sequential, computer-guided protocol

INTRODUCTION

It was the aim of the study to assess if computerized simulation and the use of thermoformed cage splints are useful to plan cases of complex craniofacial trauma.

MATERIALS AND METHODS

patients with fractures in any of the thirds of the craniofacial skeleton and occlusion impairment. Virtual surgical planning with digital reduction of fractures, navigated planning, thermoformed cage splints were used in all cases. Surgical outcomes were evaluated by computing the surface deviation and occlusograms between planned and postoperative models.

RESULTS

13 patients were enrolled in this study. Accuracy of bone repositioning was evaluated compared with the surgical planning. For the mandible, mean Root Mean Square Error (RMSE) was of 1.67 with a standard deviation (SD) of ±0.75 mm (p < 0.001); for the maxilla, average RMSE was of 0.88 with SD of ±0.52 mm (p < 0.001); and for midfacial and upper third bone segments, average RMSE was of 0.59 with SD of ±0.47 mm (p < 0.001) CONCLUSIONS: Within the limitations of the study it seems that thermoformed cage splints might be a promising alternative to other well-established approaches for accurate occlusal restoration and can be fully integrated within the digital workflow.

Accuracy of virtual planning and intraoperative navigation in zygomaticomaxillary complex fractures: A systematic review

OBJECTIVE

This systematic review aims to investigate the effect of virtual planning on the treatment of zygomaticomaxillary complex (ZMC) traumatology followed by intraoperative navigation. Furthermore, clinical outcomes following intraoperative navigation surgery or conventional surgery will be compared.

MATERIALS AND METHODS

A systematic literature search was conducted in PubMed, Embase, Web-of-Science, and Cochrane on January 1st, 2022. Inclusion criteria were articles using preoperative three-dimensional (3D) virtual planning combined with intraoperative navigation or comparing these 3D methods with conventional methods. Furthermore, at least one of the following outcomes needed to be included in the article: technical accuracy of the procedure, preoperative planning time, operative time, number of fixation points, patient satisfaction, complications, or total costs of the intervention.

RESULTS

Following the screening of 4478 articles, 17 were included. Five articles appeared to indicate a significantly better technical linear accuracy, one article reported better accuracy for rotation and two articles showed better accuracy in restoring orbital volume when using navigation. Nine articles investigated operative time with varying results. Seven articles calculated the additional costs, of which three concluded no extra cost while the others indicated high additional costs or questionable cost-effectiveness.

CONCLUSION

Virtual planning and intraoperative navigation technologies have the potential to assist maxillofacial trauma surgeons in reducing ZMC fractures significantly more accurately and restoring the facial contour in a less invasive manner at an acceptable cost.

REGISTRATION

The protocol for this systematic review (CRD42020216717) was registered in the International Prospective Register of Systematic Reviews (PROSPERO).

The application of augmented reality in craniofacial bone fracture reduction: study protocol for a randomized controlled trial

Background

Augmented reality (AR) is a new technology that increases users’ perception of the real world. The purpose of this study is to evaluate the efficacy and safety of augmented reality navigation system in treatment with craniofacial fracture reduction.

Methods

This will be a single-center prospective randomized controlled trial. Twenty-two patients will be assigned to two groups of 11, and those with zygomaticomaxillary complex fractures will undergo preoperative three-dimensional CT modeling and have operational plans designed. The control team will use traditional optical navigation to perform the surgery, and the experimental team will use an AR navigation system. The primary outcome measures will be the accuracy of the key points of surgical area between the preoperational surgical plan and post-operation. The secondary outcome measures will be the blood loss, operation time, bone reduction time, hospital time, and complication rate. The findings obtained through this study are expected to evaluate efficacy and safety of the augmented reality navigation system in the treatment of zygomaticomaxillary complex fractures.

Discussion

This controlled trial of augmented reality navigation system in treatment with zygomaticomaxillary complex fracture reduction will clarify the efficacy and safety of this technology by measuring the accuracy of the key points of surgical area and blood loss, operation and bone reduction times, hospital stay duration, and complication rates. This is a single-center study, and the results are expected to promote the application of augmented reality in craniofacial fracture reduction to improve surgery accuracy and efficacy.

Trial registration

Chinese Clinical Trial Registry ChiCTR1900022626. Registered on April 19, 2019.

Zygomaticomaxillary Fractures

Fractures of the zygomaticomaxillary complex and zygomatic arch are common athletic injuries. Fracture displacement can lead to midfacial retrusion and widening, causing noticeable deformity. Associated signs and symptoms include hypoesthesia of the infraorbital nerve distribution, trismus, and subjective malocclusion. Operative treatment is indicated in cases of significant displacement or functional disturbance. The approach and details of osteosynthesis are catered to the specific characteristics of the fracture. Technology, such as virtual surgical planning, intraoperative navigation, and intraoperative imaging, has the potential to improve accuracy of treating challenging fractures.

Virtual planning and navigation for targeted excision of intraorbital space-occupying lesions: proposal of a computer-guided protocol

The purpose of this study was to present an innovative approach for the preoperative assessment and intraoperative targeted excision of masses occupying the intraorbital space based on multimodal image fusion, segmentation, virtual models, digital planning, and navigation. Nineteen patients were studied and underwent surgery using the presented workflow, in both open and endoscopic procedures. Three main scenarios were standardized for the application of computer-guided surgery: single masses of the superior-lateral compartment, single masses of the inferior-medial compartment, and multifocal masses. An operative protocol was devised, and the accuracy of the osteotomies was analysed. All patients were managed successfully by applying the same protocol. No intraoperative complications were reported. The accuracy of the osteotomies was evaluated as a surrogate endpoint for the overall precision of surgery, showing average discrepancies of <1 mm for lateral marginotomies and <0.5 mm for endoscopic osteotomies. This study outlines an operative workflow for the implementation of virtual models to excise orbital masses, enhancing in-depth preoperative understanding of the anatomical relationships within the orbital space and increasing precision in both open and endoscopic approaches.