Augmented reality and physical hybrid model simulation for preoperative planning of metopic craniosynostosis surgery.

OBJECTIVE: The main objective of neurosurgery is to establish safe and reliable surgical techniques. Medical technology has advanced during the 21st century, enabling the development of increasingly sophisticated tools for preoperative study that can be used by surgeons before performing surgery on an actual patient. Laser-printed models are a robust tool for improving surgical performance, planning an operative approach, and developing the skills and strategy to deal with uncommon and high-risk intraoperative difficulties. Practice with these models enhances the surgeon's understanding of 3D anatomy but has some limitations with regard to tactile perception. In this study, the authors aimed to develop a preoperative planning method that combines a hybrid model with augmented reality (AR) to enhance preparation for and planning of a specific surgical procedure, correction of metopic craniosynostosis, also known as trigonocephaly. METHODS: With the use of imaging data of an actual case patient who underwent surgical correction of metopic craniosynostosis, a physical hybrid model (for hands-on applications) and an AR app for a mobile device were created. The hybrid customized model was developed by using analysis of diagnostic CT imaging of a case patient with metopic craniosynostosis. Created from many different types of silicone, the physical model simulates anatomical conditions, allowing a multidisciplinary team to deal with different situations and to precisely determine the appropriate surgical approach. A real-time AR interface with the physical model was developed by using an AR app that enhances the anatomic aspects of the patient's skull. This method was used by 38 experienced surgeons (craniofacial plastic surgeons and neurosurgeons), who then responded to a questionnaire that evaluated the realism and utility of the hybrid AR simulation used in this method as a beneficial educational tool for teaching and preoperative planning in performing surgical metopic craniosynostosis correction. RESULTS: The authors developed a practice model for planning the surgical cranial remodeling used in the correction of metopic craniosynostosis. In the hybrid AR model, all aspects of the surgical procedure previously performed on the case patient were simulated: subcutaneous and subperiosteal dissection, skin incision, and skull remodeling with absorbable miniplates. The pre- and postoperative procedures were also carried out, which emphasizes the role of the AR app in the hybrid model. On the basis of the questionnaire, the hybrid AR tool was approved by the senior surgery team and considered adequate for educational purposes. Statistical analysis of the questionnaire responses also highlighted the potential for the use of the hybrid model in future applications. CONCLUSIONS: This new preoperative platform that combines physical and virtual models may represent an important method to improve multidisciplinary discussion in addition to being a powerful teaching tool. The hybrid model associated with the AR app provided an effective training environment, and it enhanced the teaching of surgical anatomy and operative strategies in a challenging neurosurgical procedure.

The Potential Applications of Augmented Reality in Fetoscopic Surgery for Antenatal Treatment of Myelomeningocele.

OBJECTIVE: To develop a preoperative planning method using augmented reality (AR) of a specific surgical procedure: fetoscopy for myelomeningocele repair. METHODS: Imaging data were acquired of a pregnant woman at 27 weeks of gestation whose fetus was diagnosed with myelomeningocele. The patient was identified as a candidate for fetoscopic repair of the spine defect, and an AR application for mobile device simulation was developed. The virtual customized model was created by analysis of the presurgical magnetic resonance imaging. A real-time AR interface was developed by using an application that enhanced the anatomical aspects of both mother and fetus. RESULTS: A virtual model for planning fetoscopy repair for myelomeningocele was developed. Preoperative and postoperative procedures were successfully carried out, emphasizing the beneficial role of the AR application. The use of the AR model allowed the multidisciplinary team to engage in discussion to determine the appropriate surgical approach. It also allowed a clearer explanation of the procedure to the parents enabling a better understanding of the parents regarding specifics characteristics of their baby's spine defect. CONCLUSIONS: This new preoperative platform using a virtual model represents an important tool to improve patient's comprehension, multidisciplinary discussion, and surgical planning. In addition, it can be used worldwide as a teaching tool in the fetal surgery field.

Preoperative Planning Modalities for Meningoencephalocele: New Proof of Concept.

OBJECTIVE: Late surgical correction of meningoencephalocele is a rare scenario that remains challenging for surgeons. Three-dimensional models can mimic the correct anatomical relationships, and technological systems have brought advances to medicine. This study aims to present a novel preoperative planning modality that combines augmented reality with a hybrid model for complex malformation associated with late correction. METHODS: The present report describes a case of frontoethmoidal encephalocele of a 10-year-old girl. Two different methods for planning the approach were developed: 1) a hybrid hands-on model and 2) augmented reality, using a cell phone app and headset display. The customized hybrid model was created based on patient's imaging. The augmented reality app was developed with a real-time interface. RESULTS: The hybrid model recreated anatomic alterations, thereby allowing a multidisciplinary team to determine an appropriate surgical approach. All aspects of the surgical procedure were simulated. A pre- to postoperative comparison was made, which emphasized benefit of tridimensional anatomical relationships using augmented reality tool and its role in preoperative planning. CONCLUSIONS: The authors believe this new multimodality preoperative platform could be a useful method to improve multidisciplinary discussion as well as a powerful tool for teaching and planning.