Virtual reality with three-dimensional image guidance of individual patients' vessel anatomy in laparoscopic distal pancreatectomy

Artificial intelligence-driven 3D MRI of lumbosacral nerve root anomalies: accuracy, incidence, and clinical utility

PURPOSE

Lumbosacral nerve root anomalies are relatively rare but can be a risk factor for intraoperative nerve injury. However, it is often difficult to evaluate them with preoperative imaging. We developed a software that automatically generates three-dimensional (3D) nerve root images from magnetic resonance (MR) imaging using artificial intelligence (AI). This study aims to evaluate the accuracy and utility of this modality in clinical practice by conducting an epidemiological study of nerve root anomalies.

METHODS

The incidence and morphology of nerve root anomalies were evaluated in the 3D images of 1,500 patients. The accuracy of the images was evaluated by comparing the images generated automatically using this AI software with those created manually by conventional methods.

RESULTS

Of 1,500 cases, 53 (3.5%) had nerve root anomalies with total of 58 nerve root anomalies. With respect to the spinal level, 35 nerve root anomalies were found in the L5-S1 level, the most common (60.3%). As for morphology, 47 nerve roots (81.0%) were of the Neidre-MacNab classification Type 1. The images matched in 1,493 out of 1,500 cases (99.5%) between the two methods, and the remaining 7 cases all had nerve root abnormalities, which were detected as abnormal by the AI software.

CONCLUSION

The MR nerve root 3D imaging provided a 3D visualization and understanding of nerve root morphology, including nerve root anomalies. The AI software enables easy and precise 3D nerve root imaging, which greatly aids in the preoperative evaluation for spinal surgery.

Virtual 3D models, augmented reality systems and virtual laparoscopic simulations in complicated pancreatic surgeries: state of art, future perspectives, and challenges

Pancreatic surgery is considered one of the most challenging interventions by many surgeons, mainly due to retroperitoneal location and proximity to key and delicate vascular structures. These factors make pancreatic resection a demanding procedure, with successful rates far from optimal and frequent postoperative complications. Surgical planning is essential to improve patient outcomes, and in this regard, many technological advances made in the last few years have proven to be extremely useful in medical fields. This review aims to outline the potential and limitations of 3D digital and 3D printed models in pancreatic surgical planning, as well as the impact and challenges of novel technologies such as augmented/virtual reality systems or artificial intelligence to improve medical training and surgical outcomes.

State of the Art in Immersive Interactive Technologies for Surgery Simulation: A Review and Prospective

Immersive technologies have thrived on a strong foundation of software and hardware, injecting vitality into medical training. This surge has witnessed numerous endeavors incorporating immersive technologies into surgery simulation for surgical skills training, with a growing number of researchers delving into this domain. Relevant experiences and patterns need to be summarized urgently to enable researchers to establish a comprehensive understanding of this field, thus promoting its continuous growth. This study provides a forward-looking perspective by reviewing the latest development of immersive interactive technologies for surgery simulation. The investigation commences from a technological standpoint, delving into the core aspects of virtual reality (VR), augmented reality (AR) and mixed reality (MR) technologies, namely, haptic rendering and tracking. Subsequently, we summarize recent work based on the categorization of minimally invasive surgery (MIS) and open surgery simulations. Finally, the study showcases the impressive performance and expansive potential of immersive technologies in surgical simulation while also discussing the current limitations. We find that the design of interaction and the choice of immersive technology in virtual surgery development should be closely related to the corresponding interactive operations in the real surgical speciality. This alignment facilitates targeted technological adaptations in the direction of greater applicability and fidelity of simulation.

A new dimension in medical education: Virtual reality in anatomy during COVID-19 pandemic

Virtual reality technology has been increasingly used in the field of anatomy education, particularly in response to the COVID-19 pandemic. Virtual reality in anatomy (VRA) allows the creation of immersive, three-dimensional environments or experiences that can interact in a seemingly real or physical way. A comprehensive search of electronic databases was conducted to identify relevant studies. The search included studies published between 2020 and June 2023. The use of VRA education has been shown to be effective in improving students' understanding and retention of knowledge, as well as developing practical skills such as surgical techniques. VRA can allow students to visualize and interact with complex structures and systems in a way that is not possible with traditional methods. It can also provide a safe and ethical alternative to cadavers, which may be in short supply or have access restrictions. Additionally, VRA can be used to create customized learning experiences, allowing students to focus on specific areas of anatomy or to repeat certain exercises as needed. However, there are also limitations to the use of VRA education, including cost and the need for specialized equipment and training, as well as concerns about the realism and accuracy of VRA models. To fully utilize the potential of VRA education, it is important for educators to carefully consider the appropriate use of VR and to continuously evaluate its effectiveness. It is important for educators to carefully consider the appropriate use of VRA and to continuously evaluate its effectiveness to fully utilize its potential.

A scoping review on the trends of digital anatomy education

Digital technologies are changing the landscape of anatomy education. To reveal the trend of digital anatomy education across medical science disciplines, searches were performed using PubMed, EMBASE, and MEDLINE bibliographic databases for research articles published from January 2010 to June 2021 (inclusive). The search was restricted to publications written in English language and to articles describing teaching tools in undergraduate and postgraduate anatomy and pre-vocational clinical anatomy training courses. Among 156 included studies across six health disciplines, 35% used three-dimensional (3D) digital printing tools, 24.2% augmented reality (AR), 22.3% virtual reality (VR), 11.5% web-based programs, and 4.5% tablet-based apps. There was a clear discipline-dependent preference in the choice and employment of digital anatomy education. AR and VR were the more commonly adopted digital tools for medical and surgical anatomy education, while 3D printing is more broadly used for nursing, allied health and dental health education compared to other digital resources. Digital modalities were predominantly adopted for applied interactive anatomy education and primarily in advanced anatomy curricula such as regional anatomy and neuroanatomy. Moreover, there was a steep increase in VR anatomy combining digital simulation for surgical anatomy training. There is a consistent increase in the adoption of digital modalities in anatomy education across all included health disciplines. AR and VR anatomy incorporating digital simulation will play a more prominent role in medical education of the future. Combining multimodal digital resources that supports blended and interactive learning will further modernize anatomy education, moving medical education further away from its didactic history.

Patient-specific virtual three-dimensional surgical navigation for gastric cancer surgery: A prospective study for preoperative planning and intraoperative guidance

Introduction

Abdominal computed tomography (CT) can accurately demonstrate organs and vascular structures around the stomach, and its potential role for image guidance is becoming increasingly established. However, solely using two-dimensional CT images to identify critical anatomical structures is undeniably challenging and not surgeon-friendly. To validate the feasibility of a patient-specific 3-D surgical navigation system for preoperative planning and intraoperative guidance during robotic gastric cancer surgery.

Materials and methods

A prospective single-arm open-label observational study was conducted. Thirty participants underwent robotic distal gastrectomy for gastric cancer using a virtual surgical navigation system that provides patient-specific 3-D anatomical information with a pneumoperitoneum model using preoperative CT-angiography. Turnaround time and the accuracy of detecting vascular anatomy with its variations were measured, and perioperative outcomes were compared with a control group after propensity-score matching during the same study period.

Results

Among 36 registered patients, 6 were excluded from the study. Patient-specific 3-D anatomy reconstruction was successfully implemented without any problems in all 30 patients using preoperative CT. All vessels encountered during gastric cancer surgery were successfully reconstructed, and all vascular origins and variations were identical to operative findings. The operative data and short-term outcomes between the experimental and control group were comparable. The experimental group showed shorter anesthesia time (218.6 min vs. 230.3 min; P=0.299), operative time (177.1 min vs. 193.9 min; P=0.137), and console time (129.3 min vs. 147.4 min; P=0.101) than the control group, although the differences were not statistically significant.

Conclusions

Patient-specific 3-D surgical navigation system for robotic gastrectomy for gastric cancer is clinically feasible and applicable with an acceptable turnaround time. This system enables patient-specific preoperative planning and intraoperative navigation by visualizing all the anatomy required for gastrectomy in 3-D models without any error.

Clinical trial registration

Clinicaltrials.gov, identifier NCT05039333.

Flipped anatomy classroom integrating multimodal digital resources shows positive influence upon students' experience and learning performance

Anatomy is shifting toward a greater focus on adopting digital delivery. To advance digital and authentic learning in anatomy, a flipped classroom model integrating multimodal digital resources and a multimedia group assignment was designed and implemented for first-year neuroanatomy and third-year regional anatomy curricula. A five-point Likert scale learning and teaching survey was conducted for a total of 145 undergraduate health science students to evaluate students' perception of the flipped classroom model and digital resources. This study revealed that over two-thirds of participants strongly agreed or agreed that the flipped classroom model helped their independent learning and understanding of difficult anatomy concepts. The response showed students consistently enjoyed their experience of using multimodal digital anatomy resources. Both first-year (75%) and third-year (88%) students strongly agreed or agreed that digital tools are very valuable and interactive for studying anatomy. Most students strongly agreed or agreed that digital anatomy tools increased their learning experience (~80%) and confidence (> 70%). The third-year students rated the value of digital anatomy tools significantly higher than the first-year students (p = 0.0038). A taxonomy-based assessment strategy revealed that the third-year students, but not the first-year, demonstrated improved performance in assessments relating to clinical application (p = 0.045). In summary, a flipped anatomy classroom integrating multimodal digital approaches exerted positive impact upon learning experience of both junior and senior students, the latter of whom demonstrated improved learning performance. This study extends the pedagogy innovation of flipped classroom teaching, which will advance future anatomy curriculum development, pertinent to post-pandemic education.

The Opportunities and Challenges of Digital Anatomy for Medical Sciences: Narrative Review

BACKGROUND

Anatomy has been the cornerstone of medical education for centuries. However, given the advances in the Internet of Things, this landscape has been augmented in the past decade, shifting toward a greater focus on adopting digital technologies. Digital anatomy is emerging as a new discipline that represents an opportunity to embrace advances in digital health technologies and apply them to the domain of modern medical sciences. Notably, the use of augmented or mixed and virtual reality as well as mobile and platforms and 3D printing in modern anatomy has dramatically increased in the last 5 years.

OBJECTIVE

This review aims to outline the emerging area of digital anatomy and summarize opportunities and challenges for incorporating digital anatomy in medical science education and practices.

METHODS

Literature searches were performed using the PubMed, Embase, and MEDLINE bibliographic databases for research articles published between January 2005 and June 2021 (inclusive). Out of the 4650 articles, 651 (14%) were advanced to full-text screening and 77 (1.7%) were eligible for inclusion in the narrative review. We performed a Strength, Weakness, Opportunity, and Threat (SWOT) analysis to evaluate the role that digital anatomy plays in both the learning and teaching of medicine and health sciences as well as its practice.

RESULTS

Digital anatomy has not only revolutionized undergraduate anatomy education via 3D reconstruction of the human body but is shifting the paradigm of pre- and vocational training for medical professionals via digital simulation, advancing health care. Importantly, it was noted that digital anatomy not only benefits in situ real time clinical practice but also has many advantages for learning and teaching clinicians at multiple levels. Using the SWOT analysis, we described strengths and opportunities that together serve to underscore the benefits of embracing digital anatomy, in particular the areas for collaboration and medical advances. The SWOT analysis also identified a few weaknesses associated with digital anatomy, which are primarily related to the fact that the current reach and range of applications for digital anatomy are very limited owing to its nascent nature. Furthermore, threats are limited to technical aspects such as hardware and software issues.

CONCLUSIONS

This review highlights the advances in digital health and Health 4.0 in key areas of digital anatomy analytics. The continuous evolution of digital technologies will increase their ability to reinforce anatomy knowledge and advance clinical practice. However, digital anatomy education should not be viewed as a simple technical conversion and needs an explicit pedagogical framework. This review will be a valuable asset for educators and researchers to incorporate digital anatomy into the learning and teaching of medical sciences and their practice.

Precision vascular anatomy for minimally invasive distal pancreatectomy: A systematic review

BACKGROUND

Minimally invasive distal pancreatectomy (MIDP) is increasingly performed worldwide; however, the surgical anatomy required to safely perform MIDP has not yet been fully considered. This review evaluated the literature concerning peripancreatic vascular anatomy, which is considered important to conduct safe MIDP.

METHODS

A database search of PubMed and Ichushi (Japanese) was conducted. Qualified studies investigating the anatomical variations of peripancreatic vessels related to MIDP were evaluated using SIGN methodology.

RESULTS

Of 701 articles yielded by our search strategy, 76 articles were assessed in this systematic review. The important vascular anatomy required to recognize MIDP included the pancreatic parenchymal coverage on the root and the running course of the splenic artery, branching patterns of the splenic artery, confluence positions of the left gastric vein and the inferior mesenteric vein, forms of pancreatic veins including the centro-inferior pancreatic vein, characteristics of the left renal vein, and collateral routes perfusing the spleen following Warshaw's technique. Very few articles evaluating the relationship between the anatomical variations and surgical outcomes of MIDP were found.

CONCLUSIONS

The precise knowledge of peripancreatic vessels is important to adequately complete MIDP. More detailed anatomic analyses and descriptions will benefit surgeons and their patients who are facing these operations.

Simulation for Foregut and Bariatric Surgery: Current Status and Future Directions

Simulation offers the opportunity to practice in a safe, controlled, and standardized environment. Surgical simulation, in particular, is very attractive because it avoids learning and practicing surgical skills in the operating room. Many simulators are currently available such as box-lap trainers, virtual-reality platforms, cadavers, live animals, animal-based tissue blocks, and synthetic/artificial models. Endoscopic interventions can be practiced with high-fidelity virtual simulators. Box-lap trainers help practicing basic laparoscopic skills. Cadavers and live animals offer realism to train entire foregut and bariatric procedures. However, limited availability and high expenses often restrict their use. Ex vivo simulators with animal tissue blocks have been recently developed and appear to be a realistic and cost-effective alternative. Three-dimensional printing and real-time navigation systems have also emerged as promising training tools. Overall, further efforts are needed to develop a formal simulation curriculum with validated simulators for foregut and bariatric surgery.

A Novel Color-Coded Liver Metastasis Mouse Model to Distinguish Tumor and Adjacent Liver Segment

BACKGROUND

It is difficult to distinguish between a tumor and its liver segment with traditional use of indocyanine green (ICG) alone. In the present study, a method was used to limit ICG to the liver segment adjacent to a tumor. A spectrally-distinct fluorescently-labeled tumor-specific antibody against human carcinoembryonic antigen-related cell-adhesion molecules was used to label the metastatic tumor in a patient-derived orthotopic xenograft mouse model to enable color-coded visualization and distinction of a colon-cancer liver metastases and its adjacent liver segment.

MATERIALS AND METHODS

Nude mice received surgical orthotopic implantation in the liver of colon-cancer liver metastases derived from two patients. An anti- carcinoembryonic antigen-related cell-adhesion molecules monoclonal antibody (mAb 6G5j) was conjugated to a near-infrared dye IR700DX (6G5j-IR700DX). After three weeks, mice received 6G5j-IR700DX via tail-vein injection 48 hours before surgery. ICG was intravenously injected after ligation of the left or left lateral Glissonean pedicle resulting in labeling of the segment with preserved blood-flow in the liver. Imaging was performed with the Pearl Trilogy and FLARE Imaging Systems.

RESULTS

The metastatic liver tumor had a clear fluorescence signal due to selective tumor targeting by 6G5j-IR700DX, which was imaged on the 700 nm channel. The adjacent liver segment, with preserved blood-flow in the liver, had a clear fluorescence ICG 800 nm signal, while the left or left lateral segment had no fluorescence signal. Overlay of the images showed clear color-coded differentiation between the tumor fluorescing at 700 nm and the adjacent liver segment fluorescing at 800 nm.

CONCLUSIONS

Color-coding of a liver tumor and uninvolved liver segment has the potential for improved liver resection.

A review on the applications of virtual reality, augmented reality and mixed reality in surgical simulation: an extension to different kinds of surgery

Background: Research proves that the apprenticeship model, which is the gold standard for training surgical residents, is obsolete. For that reason, there is a continuing effort toward the development of high-fidelity surgical simulators to replace the apprenticeship model. Applying Virtual Reality Augmented Reality (AR) and Mixed Reality (MR) in surgical simulators increases the fidelity, level of immersion and overall experience of these simulators.Areas covered: The objective of this review is to provide a comprehensive overview of the application of VR, AR and MR for distinct surgical disciplines, including maxillofacial surgery and neurosurgery. The current developments in these areas, as well as potential future directions, are discussed.Expert opinion: The key components for incorporating VR into surgical simulators are visual and haptic rendering. These components ensure that the user is completely immersed in the virtual environment and can interact in the same way as in the physical world. The key components for the application of AR and MR into surgical simulators include the tracking system as well as the visual rendering. The advantages of these surgical simulators are the ability to perform user evaluations and increase the training frequency of surgical residents.

Peroral traction-assisted natural orifice trans-anal flexible endoscopic rectosigmoidectomy followed by intracorporeal colorectal anastomosis in a live porcine model

BACKGROUND

Compared to traditional open surgery, laparoscopic surgery has become a standard approach for colorectal cancer due to its great superiorities including less postoperative pain, a shorter hospital stay, and better quality of life. In 2007, Whiteford et al reported the first natural orifice trans-anal endoscopic surgery (NOTES) sigmoidectomy using transanal endoscopic microsurgery. To date, all cases of NOTES colorectal resection have included a hybrid laparoscopic approach with the use of established rigid platforms.

AIM

To introduce a novel technique of peroral external traction-assisted transanal NOTES rectosigmoidectomy followed by intracorporeal colorectal end-to-end anastomosis by using only currently available and flexible endoscopic instrumentation in a live porcine model.

METHODS

Three female pigs weighing 25-30 kg underwent NOTES rectosigmoid resection. After preoperative work-up and bowel preparation, general anesthesia combined with endotracheal intubation was achieved. One dual-channel therapeutic endoscope was used. Carbon dioxide insufflation was performed during the operation. The procedure of trans-anal NOTES rectosigmoidectomy included the following eight steps: (1) The rectosigmoid colon was tattooed with India ink by submucosal injection; (2) Creation of gastrostomy by directed submucosal tunneling; (3) Peroral external traction using endoloop ligation; (4) Creation of rectostomy on the anterior rectal wall by directed 3 cm submucosal tunneling; (5) Peroral external traction-assisted dissection of the left side of the colon; (6) Trans-anal rectosigmoid specimen transection, where an anvil was inserted into the proximal segment after purse-string suturing; (7) Intracorporeal colorectal end-to-end anastomosis using a circular stapler by a single stapling technique; and (8) Closure of gastrostomy using endoscopic clips. All animals were euthanized immediately after the procedure, abdominal exploration was performed, and the air-under-water leak test was carried out.

RESULTS

The procedure was completed in all three animals, with the operation time ranging from 193 min to 259 min. Neither major intraoperative complications nor hemodynamic instability occurred during the operation. The length of the resected specimen ranged from 7 cm to 13 cm. With the assistance of a trans-umbilical rigid grasper, intracorporeal colorectal, tension-free, end-to-end anastomosis was achieved in the three animals.

CONCLUSION

Peroral traction-assisted transanal NOTES rectosigmoidectomy followed by intracorporeal colorectal end-to-end anastomosis is technically feasible and reproducible in an animal model and is worthy of further improvements.