Validation of a Full-Immersion Simulation Platform for Percutaneous Nephrolithotomy Using Three-Dimensional Printing Technology

Visual extended reality tools in image-guided surgery in urology: a systematic review

PURPOSE

The aim of this systematic review is to assess the clinical implications of employing various Extended Reality (XR) tools for image guidance in urological surgery.

METHODS

In June 2023, a systematic electronic literature search was conducted using the Medline database (via PubMed), Embase (via Ovid), Scopus, and Web of Science. The search strategy was designed based on the PICO (Patients, Intervention, Comparison, Outcome) criteria. Study protocol was registered on PROSPERO (registry number CRD42023449025). We incorporated retrospective and prospective comparative studies, along with single-arm studies, which provided information on the use of XR, Mixed Reality (MR), Augmented Reality (AR), and Virtual Reality (VR) in urological surgical procedures. Studies that were not written in English, non-original investigations, and those involving experimental research on animals or cadavers were excluded from our analysis. The quality assessment of comparative and cohort studies was conducted utilizing the Newcastle-Ottawa scale, whilst for randomized controlled trials (RCTs), the Jadad scale was adopted. The level of evidence for each study was determined based on the guidelines provided by the Oxford Centre for Evidence-Based Medicine.

RESULTS

The initial electronic search yielded 1,803 papers after removing duplicates. Among these, 58 publications underwent a comprehensive review, leading to the inclusion of 40 studies that met the specified criteria for analysis. 11, 20 and 9 studies tested XR on prostate cancer, kidney cancer and miscellaneous, including bladder cancer and lithiasis surgeries, respectively. Focusing on the different technologies 20, 15 and 5 explored the potential of VR, AR and MR. The majority of the included studies (i.e., 22) were prospective non-randomized, whilst 7 and 11 were RCT and retrospective studies respectively. The included studies that revealed how these new tools can be useful both in preoperative and intraoperative setting for a tailored surgical approach.

CONCLUSIONS

AR, VR and MR techniques have emerged as highly effective new tools for image-guided surgery, especially for urologic oncology. Nevertheless, the complete clinical advantages of these innovations are still in the process of evaluation.

A new training model using the self-healing properties of supramolecular hydrogels for endoscopic combined intrarenal surgery

The combination of hydronephrosis formation, ureteroscopic imaging, and ultrasound delineation has not been included in any non-biological training model of percutaneous nephrolithotomy or endoscopic combined intrarenal surgery. We aimed to develop a realistic kidney phantom using the self-healing properties of supramolecular hydrogels for percutaneous nephrolithotomy and endoscopic combined intrarenal surgery and evaluate its suitability as a training model.Expert and resident urologists performed ultrasound-guided renal pelvic punctures and flexible ureteroscopies for endoscopic combined intrarenal surgery using a training model. Subsequently, the training model was evaluated using a 17-item Likert scale questionnaire (range, 1-5 points). After being filled with carrageenan, the collecting system was inflated, and the relationship between the collecting system volume and collecting system pressure was determined. The durability of the model was verified by repeatedly inserting a 16-Fr access sheath. Five novices and seven urology experts performed the procedure. The mean questionnaire score was 4.25 (standard deviation, 0.37). The model was able to hold 50 mL of air, and the pressure in the collecting system ranged from 6 to 33 mmHg. Repeated punctures were possible even when a 16-Fr access sheath was inserted. Our new training model included the self-healing properties of supramolecular hydrogels, which are tough and flexible and can be evaluated using ultrasonography. According to the questionnaire score, the model was highly satisfactory and has potential as a new educational tool.

Recent Advances in Surgical Simulation For Resident Education

PURPOSE OF REVIEW

Surgical simulation has become a cornerstone for the training of surgical residents, especially for urology residents. Urology as a specialty bolsters a diverse range of procedures requiring a variety of technical skills ranging from open and robotic surgery to endoscopic procedures. While hands-on supervised training on patients still remains the foundation of residency training and education, it may not be sufficient to achieve proficiency for graduation even if case minimums are achieved. It has been well-established that simulation-based education (SBE) can supplement residency training and achieve the required proficiency benchmarks.

RECENT FINDINGS

Low-fidelity modules, such as benchtop suture kits or laparoscopic boxes, can establish a strong basic skills foundation. Eventually, residents progress to high-fidelity models to refine application of technical skills and improve operative performance. Human cadavers and animal models remain the gold standard for procedural SBE. Recently, given the well-recognized financial and ethical costs associated with cadaveric and animal models, residency programs have shifted their investments toward virtual and more immersive simulations. Urology as a field has pushed the boundaries of SBE and has reached a level where unexplored modalities, e.g., 3D printing, augmented reality, and polymer casting, are widely utilized for surgical training as well as preparation for challenging cases at both the residents, attending and team training level.

Novel 3D Custom-Made Silicone Tumor Model as a Support for Teaching Surgical Oncology Principles

Alternative laboratory teaching methods are becoming increasingly desirable and effective in medical education environments. While ethical concerns associated with the use of live animals in terminal surgery laboratories have been reduced with cadaveric models, availability, and lack of pathology can limit their ability to adequately convey surgical principles and replicate clinical training. We have developed a three-dimensional (3D) custom-made silicone soft tissue tumor model using 3D-printed molds derived from canine soft tissue sarcoma computed tomography images. This novel teaching model allows users to apply surgical oncology principles and perform basic technical tasks such as incisional biopsy, margin demarcation, marginal and wide surgical excision, and inking of surgical margins. A large cohort of students in addition to a small number of professional veterinarians at different levels of specialty training followed the laboratory guidelines and evaluated the simulated tumor model based on a qualitative survey. All participants were able to successfully complete the practical training. The model also allowed the students to identify and correct technical errors associated with biopsy sampling and margin dissection, and to understand the clinical impacts related to those errors. Face and content validity of the model were assessed using Likert-style questionnaires with overall average instructors' scores of 3.8/5 and 4.6/5, respectively. Content validity assessment of the model by the students approximated instructors' evaluation with an overall average score of 4.4/5. This model development emphasizes the efficacy of alternative non-cadaveric laboratory teaching tools and could become a valuable aid in the veterinary curricula.

Simulation-based education in urology - an update

Over the past 30 years surgical training, including urology training, has changed from the Halstedian apprenticeship-based model to a competency-based one. Simulation-based education (SBE) is an effective, competency-based method for acquiring both technical and non-technical surgical skills and has rapidly become an essential component of urological education. This article introduces the key learning theory underpinning surgical education and SBE, discussing the educational concepts of mastery learning, deliberate practice, feedback, fidelity and assessment. These concepts are fundamental aspects of urological education, thus requiring clinical educators to have a detailed understanding of their impact on learning to assist trainees to acquire surgical skills. The article will then address in detail the current and emerging simulation modalities used in urological education, with specific urological examples provided. These modalities are part-task trainers and 3D-printed models for open surgery, laparoscopic bench and virtual reality trainers, robotic surgery simulation, simulated patients and roleplay, scenario-based simulation, hybrid simulation, distributed simulation and digital simulation. This article will particularly focus on recent advancements in several emerging simulation modalities that are being applied in urology training such as operable 3D-printed models, robotic surgery simulation and online simulation. The implementation of simulation into training programmes and our recommendations for the future direction of urological simulation will also be discussed.

Remote surgical education using synthetic models combined with an augmented reality headset

Objective

The objective was to investigate the use of an augmented reality headset to remotely train clinicians on medical devices using anatomic models.

Design

Disease-specific phantoms were developed to train physicians in mpMRI-guided fusion prostate biopsy, brachytherapy, and rectal spacer insertion. Training was remotely demonstrated using 1-way virtual video conferencing format. Participants responded to an educational content survey. A heads-up display with software and augmented reality was used for remote 2-way training with the proctor and student using on their own phantoms.

Setting

The virtual video meeting took place during a prostate cancer conference in 2020, while the augmented reality training occurred in 2021. The proctor and student wore a heads-up display containing a projector and webcam where the ultrasound image was displayed onto a see-through optic along with the physician's hands. The heads-up display allowed the proctor to teach by line-of-sight while the student watched and repeated the steps.

Participants

Faculty with expertise with the medical devices used in these procedures provided training to urologists unfamiliar with these techniques.

Results

Participants responded that the 1-way training on the phantoms was realistic and mimicked human tissue. A total of 70.9% requested more training or training on the phantoms. The remote training platform was successfully beta tested at the 2 locations in transperineal prostate biopsy and rectal spacer insertion.

Conclusion

Remote training using augmented reality eliminates the need for travel. For training programs and workshops, this technology may mitigate the risk of infectious exposures, reduce training cost, and increase proctor availability, allowing training from their own institution or clinic.This investigation qualifies for the Accreditation Council for Graduate Medical Education competency in medical knowledge.

Role of three dimensional (3D) printing in endourology: An update from EAU young academic urologists (YAU) urolithiasis and endourology working group

The management of nephrolithiasis has been complemented well by modern technological advancements like virtual reality, three-dimensional (3D) printing etc. In this review, we discuss the applications of 3D printing in treating stone disease using percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS). PCNL surgeries, when preceded by a training phase using a 3D printed model, aid surgeons to choose the proper course of action, which results in better procedural outcomes. The 3D printed models have also been extensively used to train junior residents and novice surgeons to improve their proficiency in the procedure. Such novel measures include different approaches employed to 3D print a model, from 3D printing the entire pelvicalyceal system with the surrounding tissues to 3D printing simple surgical guides.

Anatomical Engineering and 3D Printing for Surgery and Medical Devices: International Review and Future Exponential Innovations

Three-dimensional printing (3DP) has recently gained importance in the medical industry, especially in surgical specialties. It uses different techniques and materials based on patients' needs, which allows bioprofessionals to design and develop unique pieces using medical imaging provided by computed tomography (CT) and magnetic resonance imaging (MRI). Therefore, the Department of Biology and Medicine and the Department of Physics and Engineering, at the Bioastronautics and Space Mechatronics Research Group, have managed and supervised an international cooperation study, in order to present a general review of the innovative surgical applications, focused on anatomical systems, such as the nervous and craniofacial system, cardiovascular system, digestive system, genitourinary system, and musculoskeletal system. Finally, the integration with augmented, mixed, virtual reality is analyzed to show the advantages of personalized treatments, taking into account the improvements for preoperative, intraoperative planning, and medical training. Also, this article explores the creation of devices and tools for space surgery to get better outcomes under changing gravity conditions.

Validity of a patient-specific percutaneous nephrolithotomy (PCNL) simulated surgical rehearsal platform: impact on patient and surgical outcomes

INTRODUCTION

Simulators provide a safe method for improving surgical skills without the associated patient risks. Advances in rapid prototyping technology have permitted the reconstruction of patient imaging into patient-specific surgical simulations that require advanced expertise, potentially continuing the learning curve.

OBJECTIVES

To evaluate the impact of preoperative high-fidelity patient-specific percutaneous nephrolithotomy hydrogel simulations on surgical and patient outcomes.

MATERIALS AND METHODS

Between 2016 and 2017, a fellowship-trained endourologist performed 20 consecutive percutaneous nephrolithotomy procedures at an academic referral center. For the first ten patients, only standard review of patient imaging was completed. For the next ten patients, patient imaging was utilized to fabricate patient-specific models including pelvicalyceal system, kidney, stone, and relevant adjacent structures from hydrogel. The models were tested to confirm anatomic accuracy and material properties similar to live tissue. Full procedural rehearsals were completed 24-48 h before the real case. Surgical metrics and patient outcomes from both groups (rehearsal vs. standard) were compared.

RESULTS

Significant improvements in mean fluoroscopy time, percutaneous needle access attempts, complications, and additional procedures were significantly lower in the rehearsal group (184.8 vs. 365.7 s, p < 0.001; 1.9 vs. 3.6 attempts, p < 0.001; 1 vs. 5, p < 0.001; and 1 vs. 5, p < 0.001, respectively). There were no differences in stone free rates, mean patient age, body mass index, or stone size between the two groups.

CONCLUSION

This study demonstrates that patient-specific procedural rehearsal is effective reducing the experience curve for a complex endourological procedure, resulting in improved surgical performance and patient outcomes.

How specific are patient-specific simulations? Analyzing the accuracy of 3D-printing and modeling to create patient-specific rehearsals for complex urological procedures

PURPOSE

In the field of urology, 3D printing and modeling are now regularly utilized to enhance pre-operative planning, surgical training, patient-specific rehearsals (PSR), and patient education and counseling. Widespread accessibility and affordability of such technologies necessitates development of quality control measures to confirm the anatomical accuracy of these tools. Herein, we present three methods utilized to evaluate the anatomical accuracy of hydrogel PSR, developed using 3D printing and molding for pre-operative surgical rehearsals, of robotic-assisted partial nephrectomy (RAPN) and percutaneous nephrolithotomy (PCNL).

METHODS

Virtual computer-aided designs (CADs) of patient anatomy were created through segmentation of patient CT scan images. Ten patient-specific RAPN and PCNL hydrogel models were CT scanned and segmented to create a corresponding model CAD. The part compare tool (3-matic, Materialize), point-to-point measurements, and Dice similarity coefficient (DSC) analyzed surface geometry, alignment, and volumetric overlap of each model component.

RESULTS

Geometries of the RAPN parenchyma, tumor, artery, vein, and pelvicalyceal system lay within an average deviation of 2.5 mm (DSC = 0.70) of the original patient geometry and 5 mm (DSC = 0.45) of the original patient alignment. Similarly, geometries of the PCNL pelvicalyceal system and stone lay within 2.5 mm (DSC = 0.6) and within 15 mm (16% deviation) in alignment. This process enabled the refinement of our modeling process to fabricate anatomically accurate RAPN and PCNL PSR.

CONCLUSION

As 3D printing and modeling continues to have a greater impact on patient care, confirming anatomical accuracy should be introduced as a quality control measure prior to use for patient care.

SERV-CT: A disparity dataset from cone-beam CT for validation of endoscopic 3D reconstruction

In computer vision, reference datasets from simulation and real outdoor scenes have been highly successful in promoting algorithmic development in stereo reconstruction. Endoscopic stereo reconstruction for surgical scenes gives rise to specific problems, including the lack of clear corner features, highly specular surface properties and the presence of blood and smoke. These issues present difficulties for both stereo reconstruction itself and also for standardised dataset production. Previous datasets have been produced using computed tomography (CT) or structured light reconstruction on phantom or ex vivo models. We present a stereo-endoscopic reconstruction validation dataset based on cone-beam CT (SERV-CT). Two ex vivo small porcine full torso cadavers were placed within the view of the endoscope with both the endoscope and target anatomy visible in the CT scan. Subsequent orientation of the endoscope was manually aligned to match the stereoscopic view and benchmark disparities, depths and occlusions are calculated. The requirement of a CT scan limited the number of stereo pairs to 8 from each ex vivo sample. For the second sample an RGB surface was acquired to aid alignment of smooth, featureless surfaces. Repeated manual alignments showed an RMS disparity accuracy of around 2 pixels and a depth accuracy of about 2 mm. A simplified reference dataset is provided consisting of endoscope image pairs with corresponding calibration, disparities, depths and occlusions covering the majority of the endoscopic image and a range of tissue types, including smooth specular surfaces, as well as significant variation of depth. We assessed the performance of various stereo algorithms from online available repositories. There is a significant variation between algorithms, highlighting some of the challenges of surgical endoscopic images. The SERV-CT dataset provides an easy to use stereoscopic validation for surgical applications with smooth reference disparities and depths covering the majority of the endoscopic image. This complements existing resources well and we hope will aid the development of surgical endoscopic anatomical reconstruction algorithms.

3D-Printed Cold Preservation Device in Renal Autotransplantation for the Treatment of a Patient With Renal Artery Stenosis

Percutaneous transluminal angioplasty (PTRA) is a common treatment method for renal vascular disease (RVD). However, PTRA may not be effective in patients with abnormal vascular disease. Renal autotransplantation (RAT) has been used as an alternative therapy for these diseases. Restrictions due to intracorporeal kidney cold preservation and the renal function of intracorporeal RAT were not as well protected compared with open operation. We developed this technique of 3D-printed polylactide (PLA) cold jackets for laparoscopic complete intracorporeal RAT for the purpose of better protecting the renal function and determining the feasibility of this novel procedure. The procedure was successfully applied to a 51-year-old woman with bilateral renal artery stenosis. The operation time was 5 hours, and blood loss was 200 ml. The patient’s blood pressure remained constant throughout the operation, and the pressure was maintained at 120-140/70–90 mmHg without antihypertensive drugs 1 week after the operation. B-ultrasound showed that the blood flow signal of the transplanted kidney was normal and the boundary between the skin and medulla was clear. The patient was discharged 2 weeks after surgery. One year postoperatively, Doppler ultrasound of the autotransplant showed that the transplanted kidney was normal in size and shape. Radionuclide renal dynamic imaging revealed that the glomerular filtration rate (GFR) of the transplanted kidney was 36.9 ml/min. 3D-printed polylactide (PLA) cold jackets for laparoscopic complete intracorporeal RAT are a safe and effective method for the treatment of renal artery stenosis and represent a feasible method for preserving the renal function of severe renal artery stenosis patients; however, the technology is still at the exploratory stage and has room for further improvements.

First Characterization of Resident Clinical Experience at American Urological Training Programs

OBJECTIVE

To provide the first nationwide characterization of the clinical learning environment in American urological training programs.

METHODS

A survey was sent to program directors (PD) at AUA-accredited urological training programs after requesting their email address from each program coordinator (PC). The 21-question survey was designed to ascertain key components of each training environment: demographics, training model, clinic structure, and resident perception.

RESULTS

The PC of 131 AUA-accredited training programs received an email for participation, yielding the PD email for 113 programs. 60/113 (53%) PDs responded to the survey. Residents participated in clinic at the following types of hospitals: Children's 51 (85%), County/Indigent 23 (38%), Private 29 (48%), University 56 (93%), Veterans Administration 38 (63%). Prevalence of clinical training models is presented in table 1. On average, PDs estimated their residents spend 2.6 half days in clinic each week (1-6). 13 (22%) programs reported a "clinic only" rotation, varying from 1-6 months total. PDs reported time constraint and schedule to be the biggest barrier to teaching in clinic and 40% felt residents see clinic as a valuable part of their training while 30% felt residents see clinic as a necessary exercise but with limitations to learning opportunities.

CONCLUSIONS

We present the first characterization of resident participation in the clinical learning environment. Structure is highly variable and directed effort is necessary to move towards improved assessment and monitoring of resident competency in clinic.

Evolving robotic surgery training and improving patient safety, with the integration of novel technologies

INTRODUCTION

Robot-assisted surgery is becoming increasingly adopted by multiple surgical specialties. There is evidence of inherent risks of utilising new technologies that are unfamiliar early in the learning curve. The development of standardised and validated training programmes is crucial to deliver safe introduction. In this review, we aim to evaluate the current evidence and opportunities to integrate novel technologies into modern digitalised robotic training curricula.

METHODS

A systematic literature review of the current evidence for novel technologies in surgical training was conducted online and relevant publications and information were identified. Evaluation was made on how these technologies could further enable digitalisation of training.

RESULTS

Overall, the quality of available studies was found to be low with current available evidence consisting largely of expert opinion, consensus statements and small qualitative studies. The review identified that there are several novel technologies already being utilised in robotic surgery training. There is also a trend towards standardised validated robotic training curricula. Currently, the majority of the validated curricula do not incorporate novel technologies and training is delivered with more traditional methods that includes centralisation of training services with wet laboratories that have access to cadavers and dedicated training robots.

CONCLUSIONS

Improvements to training standards and understanding performance data have good potential to significantly lower complications in patients. Digitalisation automates data collection and brings data together for analysis. Machine learning has potential to develop automated performance feedback for trainees. Digitalised training aims to build on the current gold standards and to further improve the 'continuum of training' by integrating PBP training, 3D-printed models, telementoring, telemetry and machine learning.

Constructing an Individualized Middle Cerebral Artery Model Using 3D Printing and Hydrogel for Bypass Training

The importance and complexity of cerebral bypass surgery (CBS) highlight the necessity for intense and dedicated training. Several available training models are yet to satisfy this need. In this technical note, we share the steps to construct a digital imaging and communications in medicine (DICOM)-based middle cerebral artery (MCA) model that is anatomically accurate, resembles handling properties of living tissue, and enables trainers to observe the cerebrovascular anatomy, improve and maintain microsurgical dexterity, and train in the essential steps of CBS. The internal and external molds were created from the geometry of DICOM-based MCA using Fusion 360 software (Autodesk, San Rafael, USA). They were then three-dimension (3D) printed using a polylactic acid filament. The 15% w/v solution of polyvinyl alcohol (PVA) was prepared and injected between the molds. Using five freeze-thaw cycles the solution was converted to tissue-mimicking cryo-gel. The model was then placed in a chloroform bath until the internal mold dissolved. To evaluate the accuracy of the MCA model, selected characteristics were measured and compared with the MCA mesh. The DICOM-based MCA model was produced using 3D printing that was available in the lab and the overall cost was less than $5 per model. The external mold required six and a half hours to be 3D printed, while the internal mold only required 23 minutes. Overall, the time required to 3D print the DICOM-based MCA model was just short of seven hours. The greatest statistically significant difference between the virtual MCA model and the DICOM-based MCA model was found in the length of the pre-bifurcation part of the M1 segment and the total length of the superior bifurcation trunk of M1 and superior branch of M2. The smallest statistically significant difference was found at the diameter of the inferior post-bifurcation trunk of the M1 segment and the diameter at the origin of the artery. This technical report aims to show the construction of a CBS training system involving the DICOM-based MCA model that demonstrates the shape of the vascular tree, resembles the handling/suturing properties of living tissue, and helps set up a homemade training station. We believe that our DICOM-based MCA model can serve as a valuable resource for CBS training throughout the world due to its cost-effectiveness and straightforward construction steps. Moreover, once the DICOM-based MCA model is used with our training station, it may offer an option for trainers to gain and maintain CBS skills despite limitations on time, cost, and space. This work was presented in February 2019 at the American Association of Neurological Surgeons/Congress of Neurological Surgeons (AANS/CNS) Cerebrovascular Section Annual Meeting held in Honolulu, Hawaii.

[Comprehensive review of 3D printing use in medicine: Comparison with practical applications in urology]

INTRODUCTION

Over the past few years, 3D printing has evolved rapidly. This has resulted in an increasing number of scientific publications reporting on the medical use of 3D printing. These applications can range from patient information, preoperative planning, education, or 3D printing of patient-specific surgical implants. The objective of this review was to give an overview of the different applications in urology and other disciplines based on a selection of publications.

METHODS

In the current narrative review the Medline database was searched to identify all the related reports discussing the use of 3D printing in the medical field and more specifically in Urology. 3D printing applications were categorized so they could be searched more thoroughly within the Medline database.

RESULTS

Three-dimensional printing can help improve pre-operative patient information, anatomy and medical trainee education. The 3D printed models may assist the surgeon in preoperative planning or become patient-specific surgical simulation models. In urology, kidney cancer surgery is the most concerned by 3D printing-related publications, for preoperative planning, but also for surgical simulation and surgical training.

CONCLUSION

3D printing has already proven useful in many medical applications, including urology, for patient information, education, pre-operative planning and surgical simulation. All areas of urology are involved and represented in the literature. Larger randomized controlled studies will certainly allow 3D printing to benefit patients in routine clinical practice.

Introducing 3D printed models of the upper urinary tract for high-fidelity simulation of retrograde intrarenal surgery

PURPOSE

Training in retrograde intrarenal surgery for the treatment of renal stone disease is a challenging task due to the unique complexity of the procedure. This study introduces a series of 3D printed models of upper urinary tract and stones designed to improve the training process.

METHODS

Six different models of upper urinary tract were algorithmically isolated, digitally optimized and 3D printed from real-life cases. Soft and hard stones in different sizes were produced from 3D printed moulds. The models were fitted onto a commercially available part-task trainer and tested for retrograde intrarenal surgery.

RESULTS

Each step of the procedure was simulated with extraordinary resemblance to real-life cases. The unique anatomical intricacy of each model and type of stones allowed us to reproduce surgeries of increasing difficulty. As the case-load required to achieve proficiency in retrograde intrarenal surgery is high, benchtop simulation could be integrated in training programs to reach good outcomes and low complication rates faster. Our models match incredible anatomical resemblance with low production cost and high reusability. Validation studies and objective skills assessment during simulations would allow comparison with other available benchtop trainers and the design of stepwise training programs.

CONCLUSIONS

3D printing is gaining a significant importance in surgical training. Our 3D printed models of the upper urinary tract might represent a risk-free training option to hasten the achievement of proficiency in endourology.

New Technologies for Kidney Surgery Planning 3D, Impression, Augmented Reality 3D, Reconstruction: Current Realities and Expectations

Purpose of review

We aim to summarize the current state of art about 3D applications in urology focusing on kidney surgeries. In addition we aim to provide a snapshot about future perspective of intraoperative applications of augmented reality (AR).

Recent findings

A variety of applications in different fields have been proposed. Many applications concern current realities and 3D reconstruction, while some others are about future perspective. The majority of recent studies have focused their attention on preoperative surgical planning, patient education, surgical training, and AR.

Summary

The disposability of 3D models in healthcare scenarios might improve surgical outcomes, learning curves of novice surgeons and residents, as well as patients’ understanding and compliance, allowing a more shared surgical decision-making.

Systematic review of three-dimensional printing for simulation training of interventional radiology trainees

RATIONALE AND OBJECTIVES

Three-dimensional (3D) printing has been utilized as a means of producing high-quality simulation models for trainees in procedure-intensive or surgical subspecialties. However, less is known about its role for trainee education within interventional radiology (IR). Thus, the purpose of this review was to assess the state of current literature regarding the use of 3D printed simulation models in IR procedural simulation experiences.

MATERIALS AND METHODS

A literature query was conducted through April 2020 for articles discussing three-dimensional printing for simulations in PubMed, Embase, CINAHL, Web of Science, and the Cochrane library databases using key terms relating to 3D printing, radiology, simulation, training, and interventional radiology.

RESULTS

We identified a scarcity of published sources, 4 total articles, that appraised the use of three-dimensional printing for simulation training in IR. While trainee feedback is generally supportive of the use of three-dimensional printing within the field, current applications utilizing 3D printed models are heterogeneous, reflecting a lack of best practices standards in the realm of medical education.

CONCLUSIONS

Presently available literature endorses the use of three-dimensional printing within interventional radiology as a teaching tool. Literature documenting the benefits of 3D printed models for IR simulation has the potential to expand within the field, as it offers a straightforward, sustainable, and reproducible means for hands-on training that ought to be standardized.

The Role of 3D-Printed Phantoms and Devices for Organ-specified Appliances in Urology

Urology is one of the fields that are always at the frontline of bringing scientific advancements into clinical practice, including 3D printing (3DP). This study aims to discuss and presents the current role of 3D-printed phantoms and devices for organ-specified applications in urology. The discussion started with a literature search regarding the two mentioned topics within PubMed, Embase, Scopus, and EBSCOhost databases. 3D-printed urological organ phantoms are reported for providing residents new insight regarding anatomical characteristics of organs, either normal or diseased, in a tangible manner. Furthermore, 3D-printed organ phantoms also helped urologists to prepare a pre-surgical planning strategy with detailed anatomical models of the diseased organs. In some centers, 3DP technology also contributed to developing specified devices for disease management. To date, urologists have been benefitted by 3D-printed phantoms and devices in the education and disease management of organs of in the genitourinary system, including kidney, bladder, prostate, ureter, urethra, penis, and adrenal. It is safe to say that 3DP technology can bring remarkable changes to daily urological practices.

Simulation-Based Training Models for Urolithiasis: A Systematic Review

Objectives: Urolithiasis is one of the most common presentations in urological practice and it is becoming increasingly important to provide structured, simulation-based training using validated training models. This systematic review aims to identify current simulation-based training models and to evaluate their validity and effectiveness. Methods: Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a comprehensive search was performed on the Medline and EMBASE databases for English language articles published between 2000 and 2018 describing and/or assessing validity of simulation models for urolithiasis procedures. Studies were qualitatively assessed for validity using the Messick validity framework and models were assigned levels of recommendation using the McGaghie model of translational outcomes. Results: A total of 98 studies were included in this study assessing 51 models, with 28 studies concerning models for urethrocystoscopy, 46 studies for ureterorenoscopy, and 39 studies for percutaneous access and/or nephrolithotomy. Only four models demonstrated a level of recommendation of 4. The most validated models were the URO/PERC-Mentor (Simbionix, Lod, Israel) with multiple studies for each across various procedural skills. Conclusion: There is a wide spectrum of simulation-based models currently available for urolithiasis procedures, mostly with limited validity evidence from small studies. Further research is required with higher levels of evidence including randomized controlled trials. In addition, long-term transfer of skills to the operating room should be assessed to establish whether there is genuine skill development and retention using simulation models and whether this helps to reduce surgical complications.

Three Dimensionally Printed Interactive Training Model for Kidney Transplantation

OBJECTIVE

The purpose of this study is to describe the development of a low-cost, reusable, interactive 3D-printed model to simulate vascular anastomoses in kidney transplantation.

DESIGN

We used a de-identified high-resolution abdominal and pelvic computed tomography scan and computer-aided design software to create a model to simulate vascular anastomoses in kidney transplantation. Surgical residents were asked to tie anastomoses and complete a survey regarding the effectiveness of the model.

SETTING

University of Michigan (Ann Arbor, Michigan)-academic, tertiary care center.

PARTICIPANTS

University of Michigan general, vascular, and cardiothoracic surgery residents participated in this study (n = 12).

RESULTS

After using the model, all 12 residents reported having a better understanding of how to set up and sew the renal artery and vein anastomoses. All 12 residents found the model to be an effective teaching tool.

CONCLUSIONS

Surgical trainees find this low-cost, reusable, interactive 3D-printed model to be an effective way to develop the technical skills necessary for vascular anastomoses in kidney transplantation.

Innovation in Urology: Three Dimensional Printing and Its Clinical Application

Three-dimensional (3D) printing allows rapid prototyping of novel equipment as well as the translation of medical imaging into tangible replicas of patient-specific anatomy. The technology has emerged as a versatile medium for innovation in medicine but with ever-expanding potential uses, does 3D printing represent a valuable adjunct to urological practice? We present a concise systematic review of articles on 3D printing within urology, outlining proposed benefits and the limitations in evidence supporting its utility. We review publications prior to December 2019 using guidelines outlined by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Of 117 identified articles, 67 are included highlighting key areas of research as the use of patient-specific models for patient education, surgical planning, and surgical training. Further novel applications included printed surgical tools, patient-specific surgical guides, and bioprinting of graft tissues. We conclude to justify its adoption within standard practice, further research is required demonstrating that use of 3D printing can produce; direct and measurable improvements in patient experience, consistent evidence of superior surgical outcomes or simulation which surpasses existing means' both in fidelity and enhancement of surgical skills. Although exploration of 3D printing's urological applications remains nascent, the seemingly limitless scope for innovation and collaborative design afforded by the technology presents undeniable value as a resource and assures a place at the forefront of future advances.

Current Status of Simulation Training in Urology: A Non-Systematic Review

Simulation has emerged as an effective solution to increasing modern constraints in surgical training. It is recognized that a larger proportion of surgical complications occur during the surgeon's initial learning curve. The simulation takes the learning curve out of the operating theatre and facilitates training in a safe and pressure-free environment whilst focusing on patient safety. The cost of simulation is not insignificant and requires commitment in funding, human resources and logistics. It is therefore important for trainers to have evidence when selecting various simulators or devices. Our non-systematic review aims to provide a comprehensive up-to-date picture on urology simulators and the evidence for their validity. It also discusses emerging technologies and future directions. Urologists should embed evidence-based simulation in training programs to shorten learning curves while maintaining patient safety and work should be directed toward a validated and agreed curriculum.

Personalized Renal Collecting System Mockup for Procedural Training Under Ultrasound Guidance

Objective: In recent years, there has been increasing interest in the use of ultrasound guidance for endoscopic and percutaneous procedures. Kidney mockups could be used for training, however, available mockups are normally incompatible with ultrasound imaging. We developed a reproducible method to manufacture an ultrasound-compatible collecting system mockup that can be made at urology laboratories. Methods: Positive and negative molding methods were used. A three-dimensional (3D) digital model of a urinary collecting system and the overlying skin surface were segmented from computed tomography. A containment mold (negative) was made following the shape of the skin surface using 3D printing. A collecting system mold (positive) was also 3D printed, but made of a dissolvable material. The containment mold was filled with a gelatin formula with the collecting system mold submersed in situ within. After the gelatin solidified, a solution was used to dissolve the collecting system mold, but not the gelatin, leaving a cavity with the shape of the collecting system. The gelatin was extracted from the container mockup and the collecting system cavity was filled with water. The mockup was imaged with ultrasound to assess echogenicity and suitability for simulating ultrasound-guided procedures. Results: A clear shape corresponding to the collecting system was observed inside the gel structure. Structural integrity was maintained with no observable manufacturing marks or separation seams. Ultrasound images of the mockup demonstrated clear differentiation at the gelatin/water interface. A mock stone was placed in the collecting system and needle targeted to simulate percutaneous needle access. Conclusion: We developed a simple method to manufacture a personalized mockup of the renal collecting system of a patient that can be used for ultrasound-guided percutaneous needle access. Generic collecting system mockups can be used for training, and patient-specific models can be used to simulate and decide the best access path before a clinical case.

Performance Optimization Strategies for Complex Endourologic Procedures

OBJECTIVE

To identify and address factors that may impact a surgeon's performance during endourologic procedures.

METHODS

A literature review was performed for articles focusing on surgical ergonomics, education, sports and performance psychology.

RESULTS

As urologists and trainees have become more comfortable approaching complex pathology endoscopically, there remains an opportunity to refine surgeon-related factors and optimize extrinsic factors to maximize efficiency and provide patients with the highest quality outcomes and safety.

CONCLUSION

Medical centers and training programs should strive to include formal lessons on stress-coping mechanisms, communication, and dedicated ergonomic training, as these all play a role in physician well-being and may lead to improved clinical outcomes.

Simulation Training in Urology: State of the Art and Future Directions

There has been a major shift from the old paradigm of 'see one, do one, teach one' in medical training due in large part to resident work-hour restrictions and required oversight in the operating room. In response to this, advancements in technology have allowed for the introduction of more objective measures to assess the skill competency and proficiency of surgical trainees. Patient safety and trainee well-being are important drivers for this new model, and so surgical training programs are adopting simulation into their curriculum. Urology is uniquely positioned at the forefront of new emerging technologies in surgery, because of the field's commitment to safe and efficient minimally invasive surgery and endourological procedures. Due to these technically challenging procedures, urological training must incorporate these educational technologies to allow for objective skills assessment, skills transfer, and ultimately providing optimal patient care with the production of proficient and competent urological trainees.

Incorporation and validation of clinically relevant performance metrics of simulation (CRPMS) into a novel full-immersion simulation platform for nerve-sparing robot-assisted radical prostatectomy (NS-RARP) utilizing three-dimensional printing and hydrogel casting technology

OBJECTIVES

To incorporate and validate clinically relevant performance metrics of simulation (CRPMS) into a hydrogel model for nerve-sparing robot-assisted radical prostatectomy (NS-RARP).

MATERIALS AND METHODS

Anatomically accurate models of the human pelvis, bladder, prostate, urethra, neurovascular bundle (NVB) and relevant adjacent structures were created from patient MRI by injecting polyvinyl alcohol (PVA) hydrogels into three-dimensionally printed injection molds. The following steps of NS-RARP were simulated: bladder neck dissection; seminal vesicle mobilization; NVB dissection; and urethrovesical anastomosis (UVA). Five experts (caseload >500) and nine novices (caseload <50) completed the simulation. Force applied to the NVB during the dissection was quantified by a novel tension wire sensor system fabricated into the NVB. Post-simulation margin status (assessed by induction of chemiluminescent reaction with fluorescent dye mixed into the prostate PVA) and UVA weathertightness (via a standard 180-mL leak test) were also assessed. Objective scoring, using Global Evaluative Assessment of Robotic Skills (GEARS) and Robotic Anastomosis Competency Evaluation (RACE), was performed by two blinded surgeons. GEARS scores were correlated with forces applied to the NVB, and RACE scores were correlated with UVA leak rates.

RESULTS

The expert group achieved faster task-specific times for nerve-sparing (P = 0.007) and superior surgical margin results (P = 0.011). Nerve forces applied were significantly lower for the expert group with regard to maximum force (P = 0.011), average force (P = 0.011), peak frequency (P = 0.027) and total energy (P = 0.003). Higher force sensitivity (subcategory of GEARS score) and total GEARS score correlated with lower nerve forces (total energy in Joules) applied to NVB during the simulation with a correlation coefficient (r value) of -0.66 (P = 0.019) and -0.87 (P = 0.000), respectively. Both total and force sensitivity GEARS scores were significantly higher in the expert group compared to the novice group (P = 0.003). UVA leak rate highly correlated with total RACE score r value = -0.86 (P = 0.000). Mean RACE scores were also significantly different between novices and experts (P = 0.003).

CONCLUSION

We present a realistic, feedback-driven, full-immersion simulation platform for the development and evaluation of surgical skills pertinent to NS-RARP. The correlation of validated objective metrics (GEARS and RACE) with our CRPMS suggests their application as a novel method for real-time assessment and feedback during robotic surgery training. Further work is required to assess the ability to predict live surgical outcomes.

Novel Education and Simulation Tools in Urologic Training

PURPOSE OF REVIEW

Postgraduate medical training has evolved considerably from an emphasis on hands-on, autonomous learning to a paradigm where simulation technologies are used to introduce and augment certain skill sets. This review is intended to provide an update on surgical simulators and tools for urological trainee education.

RECENT FINDINGS

We provide an overview of simulation platforms for robotics, endoscopy, and laparoscopic practice and training. In general, these simulators provide face, content, and construct validity. Various educational and evaluation tools have been adopted. Simulation platforms have been developed for technical and non-technical surgical skills, educational bootcamps, and tools for evaluation and feedback. While trainees find the opportunity to practice their skills beneficial, there may be difficulty with access due to cost and availability. Additionally, there is a need for more objective metrics demonstrating improvement in skill or patient outcome.

Current applications of three-dimensional printing in urology

Three-dimensional (3D) printing or additive manufacturing is a new technology that has seen rapid development in recent years with decreasing costs. 3D printing allows the creation of customised, finely detailed constructs. Technological improvements, increased printer availability, decreasing costs, improved cell culture techniques, and biomaterials have enabled complex, novel and individualised medical treatments to be developed. Although the long-term goal of printing biocompatible organs has not yet been achieved, major advances have been made utilising 3D printing in biomedical engineering. In this literature review, we discuss the role of 3D printing in relation to urological surgery. We highlight the common printing methods employed and show examples of clinical urological uses. Currently, 3D printing can be used in urology for education of trainees and patients, surgical planning, creation of urological equipment, and bioprinting. In this review, we summarise the current applications of 3D-printing technology in these areas of urology.

3D printing technology and its role in urological training

PURPOSE

Surgical simulation and 3D printing have both been gaining traction exclusively over the past decade, and now have started to appear simultaneously in current research. The opinion that surgical simulation should be part of surgery curricula is becoming ever more apparent. In this review, we highlight and briefly examine the 3D printing workflow, and each facet of the current body of literature using this technology in the augmentation of surgical training, in addition to the challenges currently faced.

METHODS

A broad literature search was conducted pertaining to the utilisation of 3D printing in urology, aiming to sample the majority of use-cases of this fairly novel technology. The 3D printing workflow, current use-cases of 3D printing as applied to urological training, and challenges faced have been described.

RESULTS

A respectable number of surgical use-cases utilising 3D printing technology in their development were identified, including but not limited to percutaneous nephrolithotomy, partial nephrectomy, renal transplantation, laparoscopic pyeloplasty, prostate brachytherapy, transurethral resection of bladder tumours, urethrovesical anastomosis simulation devices, in addition to laparoscopic trainers and robotic surgery phantoms.

CONCLUSION

Over the last decade, urology has taken this cutting-edge technology in its stride; flaunting its efficacy in the augmentation of a number of procedural training applications. The number of use cases for this technology is only expected to rise as its virtues are demonstrated, the ease of use and availability of 3D printing units advances, and costs abated.

Review of the effect of 3D medical printing and virtual reality on urology training with ‘MedTRain3DModsim’ Erasmus + European Union Project

Background/aim

It is necessary to incorporate novel training modalities in medical education, especially in surgical fields, because of the limitations of cadaveric training. Traditional medical education has many drawbacks, such as residency working hour restrictions, patient safety conflicts with the learning needs, and the lack of hands-on workshops. The MedTRain3DModsim Project aimed to produce 3-dimensional (3D) medical printed models, simulations, and innovative applications for every level of medical training using novel worldwide technologies. It was aimed herein to improve the interdisciplinary and transnational approaches, and accumulate existing experience for medical education, postgraduate studies, and specialty training.

Materials and methods

This project focused on models of solid organs and the urinary system, including the kidney, prostate, ureter, and liver. With 3D medical printing, it is possible to produce a body part from inert materials in just a few hours with the standardization of medical 3D modeling.

Results

The target groups of this project included medical students and residents, graduate students from engineering departments who needed medical education and surgical training, and medical researchers interested in health technology or clinical and surgical an atomy.

Conclusion

It was also intended to develop a novel imaging platform for education and training by reevaluating the existing data using new software and 3D modalities. Therefore, it was believed that our methodology could be implemented in all related medical fields.

Training in robotic surgery, replicating the airline industry. How far have we come?

Introduction

As the role of robot-assisted surgery continues to expand, development of standardised and validated training programmes is becoming increasingly important. We aim to compare current robotic training curricula with training in aviation, to evaluate current similarities and to provide insight into how healthcare can further learn from replicating initiatives in aviation training.

Methods

A systematic literature review of the current evidence was conducted online and relevant publications and information were identified. Evaluation and comparison between training in robotic surgery and the aviation industry was performed.

Results

There are significant similarities between modern robotic training curricula and pilot training. Both undergo basic training before proceeding to advanced training. Aviation training methods include classroom instruction, e-learning and practical training, in both the aircraft and flight simulation training devices. Both surgeon and pilot training include technical and procedural instruction as well as training in non-technical skills such as crisis management, decision making, leadership and communication. However, there is more regulation in aviation, with international standards for training curricula, simulation devices and instructors/trainers that are legally binding. Continuous learning with re-qualification with benchmarked high stakes tests are also mandatory throughout a pilot’s and instructor’s career.

Conclusion

Robotic surgeons and pilots roles have many fundamental similarities. Both work with expensive and complex technology requiring high levels of skills, within working environments with high physiological and psychological stress levels. Whilst many initiatives in aviation training have already been replicated in surgical training there remain considerable differences in regulation. Adopting established and proven aviation methods of assessment and regulation could help robotic surgical training become more efficient, more effective and ultimately safer.

Use 3D printing technology to enhance stone free rate in single tract percutaneous nephrolithotomy for the treatment of staghorn stones

This study assesses the feasibility and effectiveness of using a three-dimensional (3D) printing model for preoperative planning in the treatment of full staghorn stones, specifically in the selection of the most optimal calyx for puncture. Twelve patients were enrolled in this trial. A preoperative CT taken in prone position was performed on each of the patients. 3D models were reconstructed using digital imaging and 3D printers. Three identical models were printed for each patient. Three puncture sites from the upper-, middle-, and lower-pole calyces of the kidney models were selected for simulation of percutaneous nephrolithotomy. The stone-free rates were recorded after each of the simulations. The puncture site that yielded the maximum SFR was translated to the patient for the actual procedure. CT was performed postoperatively on both patients and simulation models. The SFR of patients and simulation models was compared. Correlation analysis and consistency analysis suggested that there was a high degree of consistency between patients and 3D-printed models. The Pearson product-moment correlation coefficient r for the postoperative stone volume of the patients (PoSVP) and postoperative stone volume of the models (PoSVM) was 0.972 (P < 0.001, 95% CI = 0.900-0.992). The Bland-Altman plot of PoSVP to PoSVM showed an icon of 95% consistency 205.8(- 725.5 ~ 1137.1), and 100% of the points were within the 95% limits of agreement. 3D-printed models can potentially be used for preoperative planning in the treatment of full staghorn stones, especially in the selection of the most optimal calyx for puncture.

An overview on 3D printing for abdominal surgery

BACKGROUND

Three-dimensional (3D) printing is a disruptive technology that is quickly spreading to many fields, including healthcare. In this context, it allows the creation of graspable, patient-specific, anatomical models generated from medical images. The ability to hold and show a physical object speeds up and facilitates the understanding of anatomical details, eases patient counseling and contributes to the education and training of students and residents. Several medical specialties are currently exploring the potential of this technology, including general surgery.

METHODS

In this review, we provide an overview on the available 3D printing technologies, together with a systematic analysis of the medical literature dedicated to its application for abdominal surgery. Our experience with the first clinical laboratory for 3D printing in Italy is also reported.

RESULTS

There was a tenfold increase in the number of publications per year over the last decade. About 70% of these papers focused on kidney and liver models, produced primarily for pre-interventional planning, as well as for educational and training purposes. The most used printing technologies are material jetting and material extrusion. Seventy-three percent of publications reported on fewer than ten clinical cases.

CONCLUSION

The increasing application of 3D printing in abdominal surgery reflects the dawn of a new technology, although it is still in its infancy. The potential benefit of this technology is clear, however, and it may soon lead to the development of new hospital facilities to improve surgical training, research, and patient care.