1.5 T augmented reality navigated interventional MRI: paravertebral sympathetic plexus injections

Randomized control trial of a holographic needle guidance technique for thoracic epidural placement

INTRODUCTION

The Microsoft HoloLens is a head-mounted mixed reality device, which allows for overlaying hologram-like computer-generated elements onto the real world. This technology can be combined with preprocedural ultrasound during thoracic epidural placement to create a visual of the ideal needle angulation and trajectory in the users' field of view. This could result in a technically easier and potentially safer alternative to traditional blind landmark techniques.

METHODS

Patients were randomly assigned to one of two groups: (1) HoloLens-assisted thoracic epidural technique (intervention-group H) or (2) traditional thoracic epidural technique (control-group C). The primary outcome was needling time (defined as skin puncture to insertion of epidural catheter) during the procedure. The secondary outcomes were number of needle punctures, number of needle movements, number of bone contacts, and epidural failure. Procedural pain and recovery room pain levels were also evaluated.

RESULTS

Eighty-three patients were included in this study. The primary outcome of procedure time was reduced in the HoloLens group compared with control (4.5 min vs 7.3 min, p=0.02, 95% CI), as was the number of needle movements required (7.2 vs 14.4, p=0.01), respectively. There was no difference in intraprocedure or postprocedure pain, bone contacts, or total number of needle punctures. Three patients in the control group experienced epidural failure versus one patient in the HoloLens group.

CONCLUSIONS

This study shows that thoracic epidural placement may be facilitated by using a guidance hologram and may be more technically efficient.

TRIAL REGISTRATION NUMBER

NCT04028284.

Development of a Head-Mounted Holographic Needle Guidance System for Enhanced Ultrasound-Guided Neuraxial Anesthesia: System Development and Observational Evaluation (Preprint)

Background

Objective

Methods

Results

Conclusions

Trial Registration

Augmented Reality Interface for Complex Anatomy Learning in the Central Nervous System: A Systematic Review

The medical system is facing the transformations with augmentation in the use of medical information systems, electronic records, smart, wearable devices, and handheld. The central nervous system function is to control the activities of the mind and the human body. Modern speedy development in medical and computational growth in the field of the central nervous system enables practitioners and researchers to extract and visualize insight from these systems. The function of augmented reality is to incorporate virtual and real objects, interactively running in a real-time and real environment. The role of augmented reality in the central nervous system becomes a thought-provoking task. Gesture interaction approach-based augmented reality in the central nervous system has enormous impending for reducing the care cost, quality refining of care, and waste and error reducing. To make this process smooth, it would be effective to present a comprehensive study report of the available state-of-the-art-work for enabling doctors and practitioners to easily use it in the decision making process. This comprehensive study will finally summarise the outputs of the published materials associate to gesture interaction-based augmented reality approach in the central nervous system. This research uses the protocol of systematic literature which systematically collects, analyses, and derives facts from the collected papers. The data collected range from the published materials for 10 years. 78 papers were selected and included papers based on the predefined inclusion, exclusion, and quality criteria. The study supports to identify the studies related to augmented reality in the nervous system, application of augmented reality in the nervous system, technique of augmented reality in the nervous system, and the gesture interaction approaches in the nervous system. The derivations from the studies show that there is certain amount of rise-up in yearly wise articles, and numerous studies exist, related to augmented reality and gestures interaction approaches to different systems of the human body, specifically to the nervous system. This research organises and summarises the existing associated work, which is in the form of published materials, and are related to augmented reality. This research will help the practitioners and researchers to sight most of the existing studies subjected to augmented reality-based gestures interaction approaches for the nervous system and then can eventually be followed as support in future for complex anatomy learning.

Integration and evaluation of a gradient-based needle navigation system for percutaneous MR-guided interventions

The purpose of the present study was to integrate an interactive gradient-based needle navigation system and to evaluate the feasibility and accuracy of the system for real-time MR guided needle puncture in a multi-ring phantom and in vivo in a porcine model. The gradient-based navigation system was implemented in a 1.5T MRI. An interactive multi-slice real-time sequence was modified to provide the excitation gradients used by two sets of three orthogonal pick-up coils integrated into a needle holder. Position and orientation of the needle holder were determined and the trajectory was superimposed on pre-acquired MR images. A gel phantom with embedded ring targets was used to evaluate accuracy using 3D distance from needle tip to target. Six punctures were performed in animals to evaluate feasibility, time, overall error (target to needle tip) and system error (needle tip to the guidance needle trajectory) in vivo. In the phantom experiments, the overall error was 6.2±2.9 mm (mean±SD) and 4.4±1.3 mm, respectively. In the porcine model, the setup time ranged from 176 to 204 seconds, the average needle insertion time was 96.3±40.5 seconds (min: 42 seconds; max: 154 seconds). The overall error and the system error was 8.8±7.8 mm (min: 0.8 mm; max: 20.0 mm) and 3.3±1.4 mm (min: 1.8 mm; max: 5.2 mm), respectively.

Augmented Reality-Guided Lumbar Facet Joint Injections

OBJECTIVES

The aim of this study was to assess feasibility and accuracy of augmented reality-guided lumbar facet joint injections.

MATERIALS AND METHODS

A spine phantom completely embedded in hardened opaque agar with 3 ring markers was built. A 3-dimensional model of the phantom was uploaded to an augmented reality headset (Microsoft HoloLens). Two radiologists independently performed 20 augmented reality-guided and 20 computed tomography (CT)-guided facet joint injections each: for each augmented reality-guided injection, the hologram was manually aligned with the phantom container using the ring markers. The radiologists targeted the virtual facet joint and tried to place the needle tip in the holographic joint space. Computed tomography was performed after each needle placement to document final needle tip position. Time needed from grabbing the needle to final needle placement was measured for each simulated injection. An independent radiologist rated images of all needle placements in a randomized order blinded to modality (augmented reality vs CT) and performer as perfect, acceptable, incorrect, or unsafe. Accuracy and time to place needles were compared between augmented reality-guided and CT-guided facet joint injections.

RESULTS

In total, 39/40 (97.5%) of augmented reality-guided needle placements were either perfect or acceptable compared with 40/40 (100%) CT-guided needle placements (P = 0.5). One augmented reality-guided injection missed the facet joint space by 2 mm. No unsafe needle placements occurred. Time to final needle placement was substantially faster with augmented reality guidance (mean 14 ± 6 seconds vs 39 ± 15 seconds, P < 0.001 for both readers).

CONCLUSIONS

Augmented reality-guided facet joint injections are feasible and accurate without potentially harmful needle placement in an experimental setting.

Augmented Reality in Medicine: Systematic and Bibliographic Review

Background

Augmented reality (AR) is a technology that integrates digital information into the user’s real-world environment. It offers a new approach for treatments and education in medicine. AR aids in surgery planning and patient treatment and helps explain complex medical situations to patients and their relatives.

Objective

This systematic and bibliographic review offers an overview of the development of apps in AR with a medical use case from March 2012 to June 2017. This work can aid as a guide to the literature and categorizes the publications in the field of AR research.

Methods

From March 2012 to June 2017, a total of 1309 publications from PubMed and Scopus databases were manually analyzed and categorized based on a predefined taxonomy. Of the total, 340 duplicates were removed and 631 publications were excluded due to incorrect classification or unavailable technical data. The remaining 338 publications were original research studies on AR. An assessment of the maturity of the projects was conducted on these publications by using the technology readiness level. To provide a comprehensive process of inclusion and exclusion, the authors adopted the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

Results

The results showed an increasing trend in the number of publications on AR in medicine. There were no relevant clinical trials on the effect of AR in medicine. Domains that used display technologies seemed to be researched more than other medical fields. The technology readiness level showed that AR technology is following a rough bell curve from levels 4 to 7. Current AR technology is more often applied to treatment scenarios than training scenarios.

Conclusions

This work discusses the applicability and future development of augmented- and mixed-reality technologies such as wearable computers and AR devices. It offers an overview of current technology and a base for researchers interested in developing AR apps in medicine. The field of AR is well researched, and there is a positive trend in its application, but its use is still in the early stages in the field of medicine and it is not widely adopted in clinical practice. Clinical studies proving the effectiveness of applied AR technologies are still lacking.