Augmented-reality telementoring for leg fasciotomy: a proof-of-concept study

A holographic telementoring system depicting surgical instrument movements for real-time guidance in open surgeries

BACKGROUND AND OBJECTIVE

During open surgeries, telementoring serves as a valuable tool for transferring surgical knowledge from a specialist surgeon (mentor) to an operating surgeon (mentee). Depicting the intended movements of the surgical instruments over the operative field improves the understanding of the required tool-tissue interaction. The objective of this work is to develop a telementoring system tailored for open surgeries, enabling the mentor to remotely demonstrate the necessary motions of surgical instruments to the mentee.

METHODS

A remote telementoring system for open surgery was implemented. The system generates visual cues in the form of virtual surgical instrument motion augmented onto the live view of the operative field. These cues can be rendered on both conventional screens in the operating room and as dynamic holograms on a head mounted display device worn by the mentee. The technical performance of the system was evaluated, where the operating room and remote location were geographically separated and connected via the Internet. Additionally, user studies were conducted to assess the effectiveness of the system as a mentoring tool.

RESULTS

The system took 307 ± 12 ms to transmit an operative field view of 1920  ×  1080 resolution, along with depth information spanning 36 cm, from the operating room to the remote location. Conversely, it took 145 ± 14 ms to receive the motion of virtual surgical instruments from the remote location back to the operating room. Furthermore, the user studies demonstrated: (a) mentor's capability to annotate the operative field with an accuracy of 3.92 ± 2.1 mm, (b) mentee's ability to comprehend and replicate the motion of surgical instruments in real-time with an average deviation of 12.8 ± 3 mm, (c) efficacy of the rendered dynamic holograms in conveying information intended for surgical instrument motion.

CONCLUSIONS

The study demonstrates the feasibility of transmitting information over the Internet from the mentor to the mentee in the form of virtual surgical instruments' motion and projecting it as holograms onto the live view of the operative field. This holds potential to enhance real-time collaborative capabilities between the mentor and the mentee during an open surgery.

Telemedicine Improves Performance of a Two-Incision Lower Leg Fasciotomy by Combat Medics: A Randomized Controlled Trial

INTRODUCTION

The primary aim of this randomized controlled trial was to assess if a head-mounted display (HMD) providing telemedicine support improves performance of a two-incision lower leg fasciotomy by a NATO special operations combat medic (combat medic).

MATERIALS AND METHODS

Thirty-six combat medics were randomized into two groups: One group performed a two-incision lower leg fasciotomy with the assistance of an HMD, while the control group completed the procedure without guidance. A Mann-Whitney U test was used to determine the possible differences in release of compartments and performance scores, as assessed by a supervising medical specialist. A Fisher's exact test was used to compare the proportions of collateral damage between groups. An independent-samples t-test was used to interpret total procedure times. The usability and technical factors involving HMD utilization were also assessed.

RESULTS

Combat medics in the HMD group released the anterior compartment (P ≤ .001) and deep posterior compartment (P = .008) significantly better. There was significantly more iatrogenic muscle (P ≤ .001) and venous damage (P ≤ .001) in the control group. The overall performance of combat medics in the HMD group was significantly better than that of the control group (P < .001). Combat medics in the control group were significantly faster (P = .012). The combat medics were very satisfied with the HMD. The HMD showed no major technical errors.

CONCLUSIONS

This randomized controlled trial shows that a HMD providing telemedicine support leads to significantly better performance of a two-incision lower leg fasciotomy by a combat medic with less iatrogenic muscle and venous damage.

Technologies Used for Telementoring in Open Surgery: A Scoping Review

Background: Telementoring technologies enable a remote mentor to guide a mentee in real-time during surgical procedures. This addresses challenges, such as lack of expertise and limited surgical training/education opportunities in remote locations. This review aims to provide a comprehensive account of these technologies tailored for open surgery. Methods: A comprehensive scoping review of the scientific literature was conducted using PubMed, ScienceDirect, ACM Digital Library, and IEEE Xplore databases. Broad and inclusive searches were done to identify articles reporting telementoring or teleguidance technologies in open surgery. Results: Screening of the search results yielded 43 articles describing surgical telementoring for open approach. The studies were categorized based on the type of open surgery (surgical specialty, surgical procedure, and stage of clinical trial), the telementoring technology used (information transferred between mentor and mentee, devices used for rendering the information), and assessment of the technology (experience level of mentor and mentee, study design, and assessment criteria). Majority of the telementoring technologies focused on trauma-related surgeries and mixed reality headsets were commonly used for rendering information (telestrations, surgical tools, or hand gestures) to the mentee. These technologies were primarily assessed on high-fidelity synthetic phantoms. Conclusions: Despite longer operative time, these telementoring technologies demonstrated clinical viability during open surgeries through improved performance and confidence of the mentee. In general, usage of immersive devices and annotations appears to be promising, although further clinical trials will be required to thoroughly assess its benefits.

Telemedicine-Guided Two-Incision Lower Leg Fasciotomy Performed by Combat Medics During Tactical Combat Casualty Care: A Feasibility Study

INTRODUCTION

During tactical combat casualty care, life- and limb-saving procedures might also be performed by combat medics. This study assesses whether it is feasible to use a head-mounted display (HMD) to provide telemedicine (TM) support from a consulted senior surgeon for combat medics when performing a two-incision lower leg fasciotomy.

MATERIALS AND METHODS

Nine combat medics were randomized into groups to perform a two-incision lower leg fasciotomy. One group used the Vuzix M400 and the second group used the RealWear HMT-1Z1. A third, control, group received no guidance. In the Vuzix M400 group and RealWear HMT-1Z1 group, a senior surgeon examined the results after the two-incision lower leg fasciotomy was finished to assess the release of compartments, possible collateral damage, and performance of the combat medics. In the control group, these results were examined by a surgical resident with expertise in two-incision lower leg fasciotomies. The resident's operative performance questionnaire was used to score the performance of the combat medics. The telehealth usability questionnaire was used to evaluate the usability of the HMDs as perceived by the combat medics.

RESULTS

Combat medics using an HMD were considered competent in performing a two-incision lower leg fasciotomy (Vuzix: median 3 [range 0], RealWear: median 3 [range 1]). These combat medics had a significantly better score in their ability to adapt to anatomical variances compared to the control group (Vuzix: median 3 [range 0], RealWear: median 3 [range 0], control: median 1 [range 0]; P = .018). Combat medics using an HMD were faster than combat medics in the control group (Vuzix: mean 14:14 [SD 3:41], RealWear: mean 15:42 [SD 1:58], control: mean 17:45 [SD 2:02]; P = .340). The overall satisfaction with both HMDs was 5 out of 7 (Vuzix: median 5 [range 0], RealWear: median 5 [range 1]; P = .317).

CONCLUSIONS

This study shows that it is feasible to use an HMD to provide TM support performance from a consulted senior surgeon for combat medics when performing a two-incision lower leg fasciotomy. The results of this study suggest that TM support might be useful for combat medics during tactical combat casualty care when performing life- and limb-saving procedures.

Virtual reality and haptic interfaces for civilian and military open trauma surgery training: A systematic review

OBJECTIVE

Virtual (VR), augmented (AR), mixed reality (MR) and haptic interfaces make additional avenues available for surgeon assessment, guidance and training. We evaluated applications for open trauma and emergency surgery to address the question: Have new computer-supported interface developments occurred that could improve trauma training for civilian and military surgeons performing open, emergency, non-laparoscopic surgery?

DESIGN

Systematic literature review.

SETTING AND PARTICIPANTS

Faculty, University of Maryland School of Medicine, Baltimore., Maryland; Womack Army Medical Center, Fort Bragg, North Carolina; Temple University, Philadelphia, Pennsylvania; Uniformed Services University of Health Sciences, and Walter Reed National Military Medical Center, Bethesda, Maryland.

METHODS

Structured literature searches identified studies using terms for virtual, augmented, mixed reality and haptics, as well as specific procedures in trauma training courses. Reporting bias was assessed. Study quality was evaluated by the Kirkpatrick's Level of evidence and the Machine Learning to Asses Surgical Expertise (MLASE) score.

RESULTS

Of 422 papers identified, 14 met inclusion criteria, included 282 enrolled subjects, 20% were surgeons, the remainder students, medics and non-surgeon physicians. Study design was poor and sample sizes were low. No data analyses were beyond descriptive and the highest outcome types were procedural success, subjective self-reports, except three studies used validated metrics. Among the 14 studies, Kirkpatrick's level of evidence was level zero in five studies, level 1 in 8 and level 2 in one. Only one study had MLASE Score greater than 9/20. There was a high risk of bias in 6 studies, uncertain bias in 5 studies and low risk of bias in 3 studies.

CONCLUSIONS

There was inadequate evidence that VR,MR,AR or haptic interfaces can facilitate training for open trauma surgery or replace cadavers. Because of limited testing in surgeons, deficient study and technology design, risk of reporting bias, no current well-designed studies of computer-supported technologies have shown benefit for open trauma, emergency surgery nor has their use shown improved patient outcomes. Larger more rigorously designed studies and evaluations by experienced surgeons are required for a greater variety of procedures and skills.

COMPETENCIES

Medical Knowledge, Practice Based Learning and Improvement, Patient Care, Systems-Based Practice.