Development and assessment of an ex-vivo bench model aimed at laparoscopic ureteric reconstructive techniques.

INTRODUCTION/BACKGROUND: Reconstructive and ablative urologic techniques require special technical mastery, especially the intracorporeal suturing. OBJECTIVE: To report the subjective evaluation of a versatile ex-vivo model aimed to practice laparoscopic ureteric reconstructive techniques (LURT) on box-trainer. STUDY DESIGN: The model is a continuous portion of porcine urinary bladder ("dilated pelvis"), the vesico-ureteral joint ("stenosis") and healthy ureter. All 127 participants (n = 119 urologists and n = 8 paediatric surgeons) performed on the model laparoscopic Anderson-Hynes dismembered pyeloplasty, and then, in the animal model, different LURT procedures (ureteroneocystostomy, ureteric reimplantation and/or dismembered pyeloplasty). The model was subjectively evaluated (face and content validity), through a 12 items questionnaire, based on a Likert scale (1-5 points) and a global question (1-10 points). RESULTS: The total mean rating for 11/12 items was very high (>4points). Only one was rated under 3 points. The overall total mean rating from 1 to 10 points was very high (9.19 ± 0.82 points). In 10/12 items, expert's feedback (content validity) prevailed over non-experts (face validity). DISCUSSION/CONCLUSION: The model was highly accepted for the practice of LURT techniques. Additionally, it is cost-effective, easy to assemble, ethically considerate, and realistic.

[Application of fluid mechanics and simulation: urinary tract and ureteral catheters.] / Aplicación de la mecánica de fluidos y la simulación: tracto urinario y catéteres ureterales.

The mechanics of urine during its transport from the renal pelvis to the bladder is of great interest for urologists. The knowledge of the different physical variables and their interrelationship, both in physiologic movements and pathologies, will help a better diagnosis and treatment. The objective of this chapter is to show the physics principles and their most relevant basic relations in urine transport, and to bring them over the clinical world. For that, we explain the movement of urine during peristalsis, ureteral obstruction and in a ureter with a stent. This explanation is based in two tools used in bioengineering: the theoretical analysis through the Theory of concontinuous media and Ffluid mechanics and computational simulation that offers a practical solution for each scenario. Moreover, we review other contributions of bioengineering to the field of Urology, such as physical simulation or additive and subtractive manufacturing techniques. Finally, we list the current limitations for these tools and the technological development lines with more future projection. CONCLUSIONS: In this chapter we aim to help urologists to understand some important concepts of bioengineering, promoting multidisciplinary cooperation to offer complementary tools that help in diagnosis and treatment of diseases.

The assessment of surgical skills as a complement to the training method. Revision.

CONTEXT AND OBJECTIVE: The acquisition and improvement of surgical skills constitute a fundamental element in the training of any practitioner. At present, however, the assessment of these skills is a scarcely developed area of research. The aim of this study was to analyse the peculiarities of the various assessment systems and establish the minimum criteria that a skills and knowledge assessment system should meet as a method for assessing surgical skills in urological surgery. ACQUISITION OF EVIDENCE: Scientific literature review aimed at the various currently available assessment systems for skills and competencies (technical and nontechnical), with a special focus on the systematic reviews and prospective studies. SUMMARY OF THE EVIDENCE: After conducting the review, we found that the various assessment systems for surgical competence have, in our opinion, a number of shortcomings. There is a certain degree of subjectivity in the assessment of surgeons by the evaluators. The assessment of nontechnical competencies is not formally recorded. There is no description of a follow-up assessment or any basic parameters associated with healthcare quality. There is no registration of associated competencies associated with the various surgical techniques. There is also no ranking of these competencies and the specific peculiarities for their application. CONCLUSIONS: We believe that the development of a new assessment system for surgical competencies (technical and nontechnical) aimed at assessing urologists in the various surgical techniques is necessary. To this end, our team has worked on developing the Evaluation System for Surgical Competencies on Laparoscopy, which is based on the definition, ranking and assessment of competencies demonstrated by surgeons.

Decomposition and analysis of laparoscopic suturing task using tool-motion analysis (TMA): improving the objective assessment.

PURPOSE: The laparoscopic suturing task is a complex procedure that requires objective assessment of surgical skills. Analysis of laparoscopic suturing task components was performed to improve current objective assessment tools. METHODS: Twelve subjects participated in this study as three groups of four surgeons (novices, intermediates and experts). A box-trainer and organic tissue were used to perform the experiment while tool movements were recorded with the augmented reality haptic system. All subjects were right-handed and developed a surgeon's knot. The laparoscopic suturing procedure was decomposed into four subtasks. Different objective metrics were applied during tool-motion analysis (TMA). Statistical analysis was performed, and results from three groups were compared using the Jonckheere-Terpstra test, considering significant differences when P ≤ 0.05. RESULTS: Several first, second and fourth subtask metrics had significant differences between the three groups. Subtasks 1 and 2 had more significant differences in metrics than subtask 4. Almost all metrics showed superior task executions accomplished by experts (lower time, total path length and number of movements) compared with intermediates and novices. CONCLUSION: The most important subtasks during suture learning process are needle puncture and first knot. The TMA could be a useful objective assessment tool to discriminate surgical experience and could be used in the future to measure and certify surgical proficiency.