Three-dimensionally printed non-biological simulator for percutaneous nephrolithotomy training

The technological future of percutaneous nephrolithotomy: a Young Academic Urologists Endourology and Urolithiasis Working Group update

PURPOSE OF REVIEW

With advancements in surgical technology along with procedural techniques, this article throws light on the latest developments and applications of artificial intelligence (AI), extended reality, 3D (three-dimensional) printing and robotics in percutaneous nephrolithotomy (PCNL).

RECENT FINDINGS

This review highlights the applications of AI in PCNL over the past 2 years. Mostly studies have been reported on development of machine learning (ML) based predicting models and identification of stone composition using deep learning convolutional neural network (DL-CNN). But owing to the complexity of the models and lack of generalizability, it is still not incorporated in the routine clinical practice. Extended reality based simulation and training models have enabled trainees to enhance their skills and shorten the learning curve. Similar advantages have been reported with the use of 3D printed models when used to train young and novice endourologists to improve their skills in percutaneous access (PCA). Applications of robotics in PCNL look promising but are still in nascent stages.

SUMMARY

Future research on PCNL should focus more on generalizability and adaptability of technological advancements in terms of training and improvement of patient outcomes.

Innovations in Kidney Stone Removal

Urolithiasis is a common clinical condition, and surgical treatment is performed with different minimally invasive procedures, such as ureteroscopy, shockwave lithotripsy and percutaneous nephrolithotomy. Although the transition from open surgery to endourological procedures to treat this condition has been a paradigm shift, ongoing technological advancements have permitted further improvement of clinical outcomes with the development of modern equipment. Such innovations in kidney stone removal are new lasers, modern ureteroscopes, development of applications and training systems utilizing three-dimensional models, artificial intelligence and virtual reality, implementation of robotic systems, sheaths connected to vacuum devices and new types of lithotripters. Innovations in kidney stone removal have led to an exciting new era of endourological options for patients and clinicians alike.

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.

Imaging in stone diagnosis and surgical planning

PURPOSE OF REVIEW

Radiological imaging techniques and applications are constantly advancing. This review will examine modern imaging techniques in the diagnosis of urolithiasis and applications for surgical planning.

RECENT FINDINGS

The diagnosis of urolithiasis may be done via plain film X-ray, ultrasound (US), or contrast tomography (CT) scan. US should be applied in the workup of flank pain in emergency rooms and may reduce unnecessary radiation exposure. Low dose and ultra-low-dose CT remain the diagnostic standard for most populations but remain underutilized. Single and dual-energy CT provide three-dimensional imaging that can predict stone-specific parameters that help clinicians predict stone passage likelihood, identify ideal management techniques, and possibly reduce complications. Machine learning has been increasingly applied to 3-D imaging to support clinicians in these prognostications and treatment selection.

SUMMARY

The diagnosis and management of urolithiasis are increasingly personalized. Patient and stone characteristics will support clinicians in treatment decision, surgical planning, and counseling.

The current and possible future role of 3D modelling within oesophagogastric surgery: a scoping review

BACKGROUND

3D reconstruction technology could revolutionise medicine. Within surgery, 3D reconstruction has a growing role in operative planning and procedures, surgical education and training as well as patient engagement. Whilst virtual and 3D printed models are already used in many surgical specialities, oesophagogastric surgery has been slow in their adoption. Therefore, the authors undertook a scoping review to clarify the current and future roles of 3D modelling in oesophagogastric surgery, highlighting gaps in the literature and implications for future research.

METHODS

A scoping review protocol was developed using a comprehensive search strategy based on internationally accepted guidelines and tailored for key databases (MEDLINE, Embase, Elsevier Scopus and ISI Web of Science). This is available through the Open Science Framework (osf.io/ta789) and was published in a peer-reviewed journal. Included studies underwent screening and full text review before inclusion. A thematic analysis was performed using pre-determined overarching themes: (i) surgical training and education, (ii) patient education and engagement, and (iii) operative planning and surgical practice. Where applicable, subthemes were generated.

RESULTS

A total of 56 papers were included. Most research was low-grade with 88% (n = 49) of publications at or below level III evidence. No randomised control trials or systematic reviews were found. Most literature (86%, n = 48) explored 3D reconstruction within operative planning. These were divided into subthemes of pre-operative (77%, n = 43) and intra-operative guidance (9%, n = 5). Few papers reported on surgical training and education (14%, n = 8), and were evenly subcategorised into virtual reality simulation (7%, n = 4) and anatomical teaching (7%, n = 4). No studies utilising 3D modelling for patient engagement and education were found.

CONCLUSION

The use of 3D reconstruction is in its infancy in oesophagogastric surgery. The quality of evidence is low and key themes, such as patient engagement and education, remain unexplored. Without high quality research evaluating the application and benefits of 3D modelling, oesophagogastric surgery may be left behind.

3-D modeling applications in ultrasound education: a systematic review

Ultrasound offers a real-time 2-D view of structures within the human body. While many medical education programs have already dedicated a portion of their curriculum to ultrasound, others are concerned about cost, accessibility and limits to student practice. Student benefit may be affected by cognitive errors, which are in part owing to the mental heuristics required to visualize a 3-D structure by interpreting a 2-D image. A possible solution to eliminating subjectivity in ultrasound interpretation is the use of 3-D models to augment the traditional 2-D ultrasound experience. PubMed, Embase and Web of Science were searched for primary literature exploring relationships between 3-D modeling applications and their use in ultrasound education. The search and review process was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist. Overall, 14 of the included 16 studies indicated a significant improvement in medical education of ultrasound with the intervention of 3-D modeling applications. This systematic review confirms that 3-D modeling applications benefit student learning in ultrasound education while illuminating the need for more research in this field.

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.

Recent advances in percutaneous lithotripsy techniques

PURPOSE OF REVIEW

To describe and critically discuss the most recent evidence regarding the percutaneous nephrolithotomy (PCNL) techniques.

RECENT FINDINGS

Three-dimensional printing and virtual reality are promising tools to improve surgeon experience and operative performance. Totally ultrasound-guided PCNL is feasible and can reduce the radiological risk. Growing evidence highlights the safety and advantages of the use of miniaturized instrumentations, although some related limitations place the mini PCNL (mPCNL) in direct challenge with the retrograde intrarenal surgery. LithoClast Trilogy and ClearPetra system can improve the stone clearance. Thulium laser is a new source of energy with growing expectations and promising in-vitro results.

SUMMARY

Significant advances have recently been recorded in PCNL techniques. Thulium fiber laser, LithoClast Trilogy, new suction devices, and the development of novel technologies for teaching and planning procedures may overcome mPCNL drawbacks. Further studies are needed to confirm the promising preliminary results available on the topic.

Validation of a Bench-Top Training Model for Retrograde Intrarenal Surgery

OBJECTIVE

To validate the in-house built Styrofoam box bench-top training model for retrograde intrarenal surgery (RIRS).

MATERIALS AND METHODS

This study was performed in the setting of a half-day RIRS course. During the course, participants performed RIRS on a locally built bench-top model. We recruited 26 participants, comprising 20 trainees and 6 experts. Trainees and experts were asked to fill a self-administered questionnaire assessing various components of RIRS to assess the face and content validity. For construct validity, experts using Objective Structured Assessment of Technical Skills (OSATS) rated trainees and the mean OSATS score of junior versus senior residents was compared.

RESULTS

As per trainees, the model was 86% (4.3/5) realistic, which was backed by experts who found this model to be 87.6% (4.38/5) realistic. The overall face validity of the model was 86.4% (4.32/5). The overall content validity of this model was 83.4% (4.17/5). Majority of the participants thought that this tool is useful for learning technique (4.38 ± 0.49) and safe-conduct (4.31 ± 0.73) of the procedure. The trainees concurred that the skills acquired are transferable to the operating room (4.23 ± 0.76). However, the construct validity by comparing mean OSATS score of junior versus senior residents was 19.5 ± 3.5 and 23 ± 4.5. A p value of 0.11 could not be established.

CONCLUSION

This study has demonstrated the face, content, and construct validity of the bench-top training model for RIRS. Further evaluation is necessary to compare its effectiveness against other available models to demonstrate concurrent validity.