See-Through Type 3D Head-Mounted Display-Based Surgical Microscope System for Microsurgery: A Feasibility Study

Assessment of head-mounted display for exoscopic neurosurgery

Background

Head-mounted display (HMD) arises as an alternative display system for surgery. This study aimed to assess the utility of a stereoscopic HMD for exoscopic neurosurgery.

Methods

The leading operator and assistants were asked to assess the various aspects of the HMD characteristics compared to the monitor display using a visual analog scale (VAS)-based questionnaire. The VAS score ranged from 0 to 10 (0, HMD was significantly inferior to the monitor; 5, HMD and monitor display were equal; and 10, HMD was significantly superior to the monitor).

Results

The surgeons and assistants used and evaluated HMD in seven exoscopic surgeries: three tumor removal, one aneurysm clipping, one anterior cervical discectomy and fusion, and two cervical laminectomy surgeries. The leading operators' assessment of HMD-based surgery was not different from monitor-based surgery; however, the assistants evaluated the field of view, overall image quality, and the assisting procedure as better in MHD-based surgery than monitor-based surgery (P = 0.039, 0.045, and 0.013, respectively).

Conclusion

HMD-based exoscopic neurosurgery can be performed at a similar quality as monitor-based surgery. Surgical assistants may benefit from using HMD-based surgery.

The Utility and Feasibility of Smart Glasses in Spine Surgery: Minimizing Radiation Exposure During Percutaneous Pedicle Screw Insertion

OBJECTIVE

Spine surgeons are often at risk of radiation exposure due to intraoperative fluoroscopy, leading to health concerns such as carcinogenesis. This is due to the increasing use of percutaneous pedicle screw (PPS) in spinal surgeries, resulting from the widespread adoption of minimally invasive spine stabilization. This study aimed to elucidate the effectiveness of smart glasses (SG) in PPS insertion under fluoroscopy.

METHODS

SG were used as an alternative screen for fluoroscopic images. Operators A (2-year experience in spine surgery) and B (9-year experience) inserted the PPS into the bilateral L1-5 pedicles of the lumbar model bone under fluoroscopic guidance, repeating this procedure twice with and without SG (groups SG and N-SG, respectively). Each vertebral body's insertion time, radiation dose, and radiation exposure time were measured, and the deviation in screw trajectories was evaluated.

RESULTS

The groups SG and N-SG showed no significant difference in insertion time for the overall procedure and each operator. However, group SG had a significantly shorter radiation exposure time than group N-SG for the overall procedure (109.1 ± 43.5 seconds vs. 150.9 ± 38.7 seconds; p = 0.003) and operator A (100.0 ± 29.0 seconds vs. 157.9 ± 42.8 seconds; p = 0.003). The radiation dose was also significantly lower in group SG than in group N-SG for the overall procedure (1.3 ± 0.6 mGy vs. 1.7 ± 0.5 mGy; p = 0.023) and operator A (1.2 ± 0.4 mGy vs. 1.8 ± 0.5 mGy; p = 0.013). The 2 groups showed no significant difference in screw deviation.

CONCLUSION

The application of SG in fluoroscopic imaging for PPS insertion holds potential as a useful method for reducing radiation exposure.

Can a Wireless Full-HD Head Mounted Display System Improve Knee Arthroscopy Performance? - A Randomized Study Using a Knee Simulator

INTRODUCTION

Our prototype wireless full-HD Augmented Reality Head-Mounted Display (AR-HMD) aims to eliminate surgeon head turning and reduce theater clutter. Learning and performance versus TV Monitors (TVM) is evaluated in simulated knee arthroscopy.

METHODS

19 surgeons and 19 novices were randomized into either the control group (A) or intervention group (B) and tasked to perform 5 simulated loose-body retrieval procedures on a bench-top knee arthroscopy simulator. A cross-over study design was adopted whereby subjects alternated between devices during trials 1-3, deemed the "Unfamiliar" phase, and then used the same device consecutively in trials 4-5, to assess performance in a more "Familiarized" state. Measured outcomes were time-to-completion and incidence of bead drops.

RESULTS

In the unfamiliar phase, HMD had 67% longer mean time-to-completion than TVM (194.7 ± 152.6s vs 116.7 ± 78.7s, P < .001). Once familiarized, HMD remained inferior to TVM, with 48% longer completion times (133.8 ± 123.3s vs 90.6 ± 55s, P = .052). Cox regression revealed device type (OR = 0.526, CI 0.391-0.709, P < .001) and number of procedure repetitions (OR = 1.186, CI 1.072-1.311, P = .001) are significantly and independently related to faster time-to-completion. However, experience is not a significant factor (OR = 1.301, CI 0.971-1.741, P = .078). Bead drops were similar between the groups in both unfamiliar (HMD: 27 vs TVM: 22, P = .65) and familiarized phases (HMD: 11 vs TVM: 17, P = .97).

CONCLUSION

Arthroscopic procedures continue to be better performed under conventional TVM. However, similar quality levels can be reached by HMD when given more time. Given the theoretical advantages, further research into improving HMD designs is advocated.

The Advantage of Using an Optical See-Through Head-Mounted Display in Ultrasonography-Guided Needle Biopsy Procedures: A Prospective Randomized Study

An optical see-through head-mounted display (OST-HMD) can potentially improve the safety and accuracy of ultrasonography (US)-guided fine-needle aspiration. We aimed to evaluate the usefulness of an OST-HMD in US-guided needle-puncture procedures. We conducted a prospective randomized controlled study in which we compared the accuracy and safety of the US-guided needle puncture procedure and the stress on the practitioner when using OST-HMD versus standard US display (SUD). Inexperienced medical students were enrolled and randomly divided into two groups. A breast phantom was used to evaluate the required time and accuracy of the US-guided needle puncture. Practitioner stress was quantified using a visual analog scale (VAS). When the procedure was performed for the first time, the time required to reach the target lesion at a shallow depth was significantly shorter in the OST-HMD group (39.8 ± 39.9 s) than in the SUD group (71.0 ± 81.0 s) (p = 0.01). Using the OST-HMD significantly reduced the unintentional puncture of a non-target lesion (p = 0.01). Furthermore, the stress felt by the practitioners when capturing the image of the target lesion (p < 0.001), inserting and advancing the needle more deeply (p < 0.001), and puncturing the target lesion (p < 0.001) was significantly reduced in the OST-HMD group compared with that in the SUD group. Use of OST-HMD may improve the accuracy and safety of US-guided needle puncture procedures and may reduce practitioner stress during the procedure.

A Cost-Effective Nucleic Acid Detection System Using a Portable Microscopic Device

A fluorescence microscope is one of the most important tools for biomedical research and laboratory diagnosis. However, its high cost and bulky size hinder the application of laboratory microscopes in space-limited and low-resource applications. Here, in this work, we proposed a portable and cost-effective fluorescence microscope. Assembled from a set of 3D print components and a webcam, it consists of a three-degree-of-freedom sliding platform and a microscopic imaging system. The microscope is capable of bright-field and fluorescence imaging with micron-level resolution. The resolution and field of view of the microscope were evaluated. Compared with a laboratory-grade inverted fluorescence microscope, the portable microscope shows satisfactory performance, both in the bright-field and fluorescence mode. From the configurations of local resources, the microscope costs around USD 100 to assemble. To demonstrate the capability of the portable fluorescence microscope, we proposed a quantitative polymerase chain reaction experiment for meat product authenticating applications. The portable and low-cost microscope platform demonstrates the benefits in space-constrained environments and shows high potential in telemedicine, point-of-care testing, and more.

Simulation-Based Estimation of the Number of Cameras Required for 3D Reconstruction in a Narrow-Baseline Multi-Camera Setup

Graphical visualization systems are a common clinical tool for displaying digital images and three-dimensional volumetric data. These systems provide a broad spectrum of information to support physicians in their clinical routine. For example, the field of radiology enjoys unrestricted options for interaction with the data, since information is pre-recorded and available entirely in digital form. However, some fields, such as microsurgery, do not benefit from this yet. Microscopes, endoscopes, and laparoscopes show the surgical site as it is. To allow free data manipulation and information fusion, 3D digitization of surgical sites is required. We aimed to find the number of cameras needed to add this functionality to surgical microscopes. For this, we performed in silico simulations of the 3D reconstruction of representative models of microsurgical sites with different numbers of cameras in narrow-baseline setups. Our results show that eight independent camera views are preferable, while at least four are necessary for a digital surgical site. In most cases, eight cameras allow the reconstruction of over 99% of the visible part. With four cameras, still over 95% can be achieved. This answers one of the key questions for the development of a prototype microscope. In future, such a system can provide functionality which is unattainable today.

Application of Mixed Reality Using Optical See-Through Head-Mounted Displays in Transforaminal Percutaneous Endoscopic Lumbar Discectomy

Purpose

Mixed reality (MixR) technology merges the real and virtual worlds to produce new environments and visualizations; it is being tested for numerous minimally invasive surgical procedures. This study is aimed at evaluating the use of MixR technology using optical see-through head-mounted displays (OST-HMDs) during transforaminal percutaneous endoscopic discectomy (TPED).

Methods

Forty-four patients treated with MixR-assisted TPED through OST-HMDs were compared with matched patients treated with conventional TPED (n = 43). In the MixR-assisted TPED group, MixR technology was used to navigate the four procedures of marking, needle insertion, foraminoplasty, and positioning of the working sheath. The clinical outcomes were evaluated based on the numerical rating scale (NRS) scores and Oswestry Disability Index (ODI) on preoperative and postoperative day 1 and at the last follow-up examination. The procedural times, radiation exposure, and eye fatigue were also recorded. All patients were followed up for at least 6 months.

Results

The NRS scores and ODI were significantly improved in both groups at the last follow-up visit compared with the preoperative values (P < 0.05); these values were not statistically different between the groups. The operation time and radiation exposure during marking, needle insertion, and total procedure significantly decreased in the MixR-assisted TPED group compared to those in the conventional TPED group (P < 0.05). Unfortunately, the incidence of eye fatigue increased owing to the use of OST-HMDs in the MixR-assisted TPED group.

Conclusion

This study shows the utility of MixR technology for image guidance in conventional TPED. Radiation exposure is decreased, and this technology serves as a valuable tool during the TPED procedure; however, the assistance of conventional fluoroscopy is still required.

Transoral laser microsurgery: feasibility of a new exoscopic HD-3D system coupled with free beam or fiber laser

In the last decades, new technological devices and instruments have been developed to overcome the technical limits of transoral laser microsurgery. The recent introduction of 3D endoscopy seems to be a promising tool in the field of diagnostic and operative laryngology as an alternative to the traditional microlaryngoscopy. Our work aims to present a novel transoral microsurgical setting that expands the use of exoscopic systems (in this case the VITOM® 3D-HD) as an alternative to the standard operating microscope. A customized support arm and an adaptor to firmly connect the VITOM® 3D-HD camera to the laser micromanipulator were specially designed. This setup was used as an alternative to the standard operating microscope in a cohort of 17 patients affected by suspicious early to intermediate pharyngo-laryngeal neoplasms. A historical cohort of patients treated with the traditional setting and matching the same inclusion criteria was used as a reference for the duration of surgical procedures. The surgical procedures comprised 7 cordectomies, 2 endoscopic partial supraglottic laryngectomies, 4 tongue base resections, and 4 lateral oropharyngectomies or hypopharyngectomies. In 6 cases (35%), a simultaneous neck dissection was performed. The low rate of positive deep (6%) or superficial (12%) margins reinforced the safety of this platform, and the results obtained in terms of operating time were comparable to the control group (p > 0.05), which confirms the feasibility of the system. Our surgical setting setup is a convincing alternative to traditional transoral laser microsurgery for early to intermediate pharyngo-laryngeal neoplasms. The main advantages of this system are comfortable ergonomics for the first surgeon and a potential benefit in terms of teaching if applied in university hospitals, since the entire surgical team can view the same surgical 3D-HD view of the first operator. Further work is still needed to objectively compare the traditional and new technique, and to validate our preliminary clinical findings.