Intraoperative Computed Tomography-Based Navigation with Augmented Reality for Lateral Approaches to the Spine

Surgical Treatment of Calcified Thoracic Herniated Disc Disease via the Transthoracic Approach with the Use of Intraoperative Computed Tomography (iCT) and Microscope-Based Augmented Reality (AR)

Background and Objectives: The aim of this study is to present our experience in the surgical treatment of calcified thoracic herniated disc disease via a transthoracic approach in the lateral position with the use of intraoperative computed tomography (iCT) and augmented reality (AR). Materials and Methods: All patients who underwent surgery for calcified thoracic herniated disc via a transthoracic transpleural approach at our Department using iCT and microscope-based AR were included in the study. Results: Six consecutive patients (five female, median age 53.2 ± 6.4 years) with calcified herniated thoracic discs (two patients Th 10-11 level, two patients Th 7-8, one patient Th 9-10, one patient Th 11-12) were included in this case series. Indication for surgery included evidence of a calcified thoracic disc on magnet resonance imaging (MRI) and CT with spinal canal stenosis of >50% of diameter, intractable pain, and neurological deficits, as well as MRI-signs of myelopathy. Five patients had paraparesis and ataxia, and one patient had no deficit. All surgeries were performed in the lateral position via a transthoracic transpleural approach (Five from left side). CT for automatic registration was performed following the placement of the reference array, with a high registration accuracy. Microscope-based AR was used, with segmented structures of interest such as vertebral bodies, disc space, herniated disc, and dural sac. Mean operative time was 277.5 ± 156 min. The use of AR improved orientation in the operative field for identification, and tailored the resection of the herniated disc and the identification of the course of dural sac. A control-iCT scan confirmed the complete resection in five patients and incomplete resection of the herniated disc in one patient. In one patient, complications occurred, such as postoperative hematoma, and wound healing deficit occurred. Mean follow-up was 22.9 ± 16.5 months. Five patients improved following surgery, and one patient who had no deficits remained unchanged. Conclusions: Optimal surgical therapy in patients with calcified thoracic disc disease with compression of dural sac and myelopathy was resectioned via a transthoracic transpleural approach. The use of iCT-based registration and microscope-based AR significantly improved orientation in the operative field and facilitated safe resection of these lesions.

Virtual, Augmented, and Mixed Reality Applications for Surgical Rehearsal, Operative Execution, and Patient Education in Spine Surgery: A Scoping Review

Background and Objectives: Advances in virtual reality (VR), augmented reality (AR), and mixed reality (MR) technologies have resulted in their increased application across many medical specialties. VR's main application has been for teaching and preparatory roles, while AR has been mostly used as a surgical adjunct. The objective of this study is to discuss the various applications and prospects for VR, AR, and MR specifically as they relate to spine surgery. Materials and Methods: A systematic review was conducted to examine the current applications of VR, AR, and MR with a focus on spine surgery. A literature search of two electronic databases (PubMed and Scopus) was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The study quality was assessed using the MERSQI score for educational research studies, QUACS for cadaveric studies, and the JBI critical appraisal tools for clinical studies. Results: A total of 228 articles were identified in the primary literature review. Following title/abstract screening and full-text review, 46 articles were included in the review. These articles comprised nine studies performed in artificial models, nine cadaveric studies, four clinical case studies, nineteen clinical case series, one clinical case-control study, and four clinical parallel control studies. Teaching applications utilizing holographic overlays are the most intensively studied aspect of AR/VR; the most simulated surgical procedure is pedicle screw placement. Conclusions: VR provides a reproducible and robust medium for surgical training through surgical simulations and for patient education through various platforms. Existing AR/MR platforms enhance the accuracy and precision of spine surgeries and show promise as a surgical adjunct.

Augmented reality in spine surgery - past, present, and future

BACKGROUND CONTEXT

Augmented reality (AR) is increasingly recognized as a valuable tool in spine surgery. Here we provides an overview of the key developments and technological milestones that have laid the foundation for AR applications in this field. We also assess the quality of existing studies on AR systems in spine surgery and explore potential future applications.

PURPOSE

The purpose of this narrative review is to examine the role of AR in spine surgery. It aims to highlight the evolution of AR technology in this context, evaluate the existing body of research, and outline potential future directions for integrating AR into spine surgery.

STUDY DESIGN

Narrative review.

METHODS

We conducted a thorough literature search to identify studies and developments related to AR in spine surgery. Relevant articles, reports, and technological advancements were analyzed to establish the historical context and current state of AR in this field.

RESULTS

The review identifies significant milestones in the development of AR technology for spine surgery. It discusses the growing body of research and highlights the strengths and weaknesses of existing investigations. Additionally, it presents insights into the potential for AR to enhance spine surgical education and speculates on future applications.

CONCLUSIONS

Augmented reality has emerged as a promising adjunct in spine surgery, with notable advancements and research efforts. The integration of AR into the spine surgery operating room holds promise, as does its potential to revolutionize surgical education. Future applications of AR in spine surgery may include real-time navigation, enhanced visualization, and improved patient outcomes. Continued development and evaluation of AR technology are essential for its successful implementation in this specialized surgical field.

The Utility and Appropriateness of Single-Position Circumferential Lumbar Interbody Fusion Using O-Arm-Based Navigation in the Novel Oblique Position

PURPOSE

Single-position surgery with patients in a lateral position, which involves inserting percutaneous pedicular screws (PPS) and lateral interbody fusion (LIF) to avoid changing the position, has been reported. The purpose of the present study was to evaluate the utility and appropriateness of single-position LIF-PPS using O-arm-based navigation in the innovative oblique position.

METHODS

This study involved a retrospective analysis of 92 consecutive patients with lumbar spondylolisthesis who underwent LIF-PPS using O-arm-based navigation. Thirty-five subjects demonstrated surgery with repositioning, as well as 24 in the lateral decubitus position, and 33 in the oblique during PPS, where the position was changed to the lateral decubitus position using bed rotation without resetting. We compared these three groups in terms of the surgery time, blood loss, and the accuracy of the screw placement.

RESULTS

The operative time was significantly shorter in the single-position surgery, both in the lateral and oblique positions, compared to surgery in a dual position. The blood loss was significantly increased in the lateral position compared to the dual and oblique positions. The screw trajectory angle on the downside was significantly smaller in the lateral position, and the accuracy of the screw placement on the downside was significantly lower in the lateral position compared to the dual and oblique positions.

CONCLUSION

Single-position surgery could reduce the average surgery time by about 60 min. The present study indicated the oblique position during PPS insertion might make single-position surgery more useful to improve the accuracy of PPS on the downside, with less blood loss.

Virtual and Augmented Reality in Spine Surgery: A Systematic Review

BACKGROUND

Augmented reality (AR) and virtual reality (VR) implementation in spinal surgery has expanded rapidly over the past decade. This systematic review summarizes the use of AR/VR technology in surgical education, preoperative planning, and intraoperative guidance.

METHODS

A search query for AR/VR technology in spine surgery was conducted through PubMed, Embase, and Scopus. After exclusions, 48 studies were included. Included studies were then grouped into relevant subsections. Categorization into subsections yielded 12 surgical training studies, 5 preoperative planning, 24 intraoperative usage, and 10 radiation exposure.

RESULTS

VR-assisted training significantly reduced penetration rates or increased accuracy rates compared to lecture-based groups in 5 studies. Preoperative VR planning significantly influenced surgical recommendations and reduced radiation exposure, operating time, and estimated blood loss. For 3 patient studies, AR-assisted pedicle screw placement accuracy ranged from 95.77% to 100% using the Gertzbein grading scale. Head-mounted display was the most common interface used intraoperatively followed by AR microscope and projector. AR/VR also had applications in tumor resection, vertebroplasty, bone biopsy, and rod bending. Four studies reported significantly reduced radiation exposure in AR group compared to fluoroscopy group.

CONCLUSIONS

AR/VR technologies have the potential to usher in a paradigm shift in spine surgery. However, the current evidence indicates there is still a need for 1) defined quality and technical requirements for AR/VR devices, 2) more intraoperative studies that explore usage outside of pedicle screw placement, and 3) technological advancements to overcome registration errors via the development of an automatic registration method.

Clinical applications of augmented reality in orthopaedic surgery: a comprehensive narrative review

PURPOSE

The development of augmented reality (AR) technology allows orthopaedic surgeons to incorporate and visualize surgical data, assisting the execution of both routine and complex surgical operations. Uniquely, AR technology allows a surgeon to view the surgical field and superimpose peri-operative imaging, anatomical landmarks, navigation guidance, and more, all in one view without the need for conjugate gaze between multiple screens. The aim of this literature review was to introduce the fundamental requirements for an augmented reality system and to assess the current applications, outcomes, and potential limitations to this technology.

METHODS

A literature search was performed using MEDLINE and Embase databases, by two independent reviewers, who then collaboratively synthesized and collated the results of the literature search into a narrative review focused on the applications of augmented reality in major orthopaedic sub-specialties.

RESULTS

Current technology requires that pre-operative patient data be acquired, and AR-compatible models constructed. Intra-operatively, to produce manipulatable virtual images into the user's view in real time, four major components are required including a camera, computer image processing technology, tracking tools, and an output screen. The user is provided with a heads-up display, which is a transparent display, enabling the user to look at both their natural view and the computer-generated images. Currently, high-quality evidence for clinical implementation of AR technology in the orthopaedic surgery operating room is lacking; however, growing in vitro literature highlights a multitude of potential applications, including increasing operative accuracy, improved biomechanical angular and alignment parameters, and potentially reduced operative time.

CONCLUSION

While the application of AR systems in surgery is currently in its infancy, we anticipate rapid and widespread implementation of this technology in various orthopaedic sub-specialties.

Navigation Techniques in Endoscopic Spine Surgery

Endoscopic spine surgery (ESS) advances the principles of minimally invasive surgery, including minor collateral tissue damage, reduced blood loss, and faster recovery times. ESS allows for direct access to the spine through small incisions and direct visualization of spinal pathology via an endoscope. While this technique has many applications, there is a steep learning curve when adopting ESS into a surgeon's practice. Two types of navigation, optical and electromagnetic, may allow for widespread utilization of ESS by engendering improved orientation to surgical anatomy and reduced complication rates. The present review discusses these two available navigation technologies and their application in endoscopic procedures by providing case examples. Furthermore, we report on the future directions of navigation within the discipline of ESS.

Editorial: Neurosurgery and Neuroanatomy

Microsurgical anatomy is not only the backbone for neurosurgical operations, but also for technological innovations, novel surgical techniques, a better understanding of the etiopathogenesis of pathologies, and translational medicine from neuroscience to daily clinical practice [...]