No description available.

The goal of this research was to establish a methodology for quantifying performance of surgeons and distinguishing skill levels during live surgeries. We integrated three physical measures (kinematics, time and movement transitions) into a modeling technique for quantifying performance of surgical trainees. We first defined a new hierarchical representation called Motor and Cognitive Modeling Diagram for laparoscopic procedures, which: (1) decomposes ‘tasks’ into ‘subtasks’ and at the very detailed level into individual movements ‘actions’; and (2) includes an explicit cognitive/motor diagrammatic representation that enables to take account of the operative variability as most intraoperative assessments are conducted at the ‘whole procedure’ level and do not distinguish between performance of trivial and complicated aspects of the procedure. Then, at each level of surgical complexity, we implemented specific mathematical techniques for providing a quantitative sense of how far a performance is located from a reference level: (1) The Kolgomorov-Smirnov statistic to describe the similarity between two empirical cumulative distribution functions (e.g., speed profiles) (2) The symmetric normalized Jensen-Shannon Divergence to compare transition probability matrices (3) The Principal Component Analysis to identify the directions of greatest variability in a multidimensional space and to reduce the dimensionality of the data using a weight space. Two experimental studies were completed in order to show feasibility of our proposed assessment methodology by monitoring movements of surgical tools while: (1) dissecting mandarin oranges, and (2) performing laparoscopic cholecystectomy procedures at the operating room to compare residents and expert surgeons when executing two surgical tasks: exposing Calot’s Triangle and dissecting the cystic duct and artery. Results demonstrated the ability of our methodology to represent selected tasks using the Motor and Cognitive Modeling Diagram and to differentiate skill levels. We aim to use our approach in future studies to establish correspondences between specific surgical tasks and the corresponding simulations of these tasks, which may ultimately enable us to do validated assessments in a simulated setting, and to test its reliability in differentiating skill levels at the operating room as the number of subjects and procedures increase.

The goal of this research was to establish a methodology for quantifying performance of surgeons and distinguishing skill levels during live surgeries. We integrated three physical measures (kinematics, time and movement transitions) into a modeling technique for quantifying performance of surgical trainees. We first defined a new hierarchical representation called Motor and Cognitive Modeling Diagram for laparoscopic procedures, which: (1) decomposes ‘tasks’ into ‘subtasks’ and at the very detailed level into individual movements ‘actions’; and (2) includes an explicit cognitive/motor diagrammatic representation that enables to take account of the operative variability as most intraoperative assessments are conducted at the ‘whole procedure’ level and do not distinguish between performance of trivial and complicated aspects of the procedure. Then, at each level of surgical complexity, we implemented specific mathematical techniques for providing a quantitative sense of how far a performance is located from a reference level: (1) The Kolgomorov-Smirnov statistic to describe the similarity between two empirical cumulative distribution functions (e.g., speed profiles) (2) The symmetric normalized Jensen-Shannon Divergence to compare transition probability matrices (3) The Principal Component Analysis to identify the directions of greatest variability in a multidimensional space and to reduce the dimensionality of the data using a weight space. Two experimental studies were completed in order to show feasibility of our proposed assessment methodology by monitoring movements of surgical tools while: (1) dissecting mandarin oranges, and (2) performing laparoscopic cholecystectomy procedures at the operating room to compare residents and expert surgeons when executing two surgical tasks: exposing Calot’s Triangle and dissecting the cystic duct and artery. Results demonstrated the ability of our methodology to represent selected tasks using the Motor and Cognitive Modeling Diagram and to differentiate skill levels. We aim to use our approach in future studies to establish correspondences between specific surgical tasks and the corresponding simulations of these tasks, which may ultimately enable us to do validated assessments in a simulated setting, and to test its reliability in differentiating skill levels at the operating room as the number of subjects and procedures increase.

The goal of this research was to establish a methodology for quantifying performance of surgeons and distinguishing skill levels during live surgeries. We integrated three physical measures (kinematics, time and movement transitions) into a modeling technique for quantifying performance of surgical trainees. We first defined a new hierarchical representation called Motor and Cognitive Modeling Diagram for laparoscopic procedures, which: (1) decomposes ‘tasks’ into ‘subtasks’ and at the very detailed level into individual movements ‘actions’; and (2) includes an explicit cognitive/motor diagrammatic representation that enables to take account of the operative variability as most intraoperative assessments are conducted at the ‘whole procedure’ level and do not distinguish between performance of trivial and complicated aspects of the procedure. Then, at each level of surgical complexity, we implemented specific mathematical techniques for providing a quantitative sense of how far a performance is located from a reference level: (1) The Kolgomorov-Smirnov statistic to describe the similarity between two empirical cumulative distribution functions (e.g., speed profiles) (2) The symmetric normalized Jensen-Shannon Divergence to compare transition probability matrices (3) The Principal Component Analysis to identify the directions of greatest variability in a multidimensional space and to reduce the dimensionality of the data using a weight space. Two experimental studies were completed in order to show feasibility of our proposed assessment methodology by monitoring movements of surgical tools while: (1) dissecting mandarin oranges, and (2) performing laparoscopic cholecystectomy procedures at the operating room to compare residents and expert surgeons when executing two surgical tasks: exposing Calot’s Triangle and dissecting the cystic duct and artery. Results demonstrated the ability of our methodology to represent selected tasks using the Motor and Cognitive Modeling Diagram and to differentiate skill levels. We aim to use our approach in future studies to establish correspondences between specific surgical tasks and the corresponding simulations of these tasks, which may ultimately enable us to do validated assessments in a simulated setting, and to test its reliability in differentiating skill levels at the operating room as the number of subjects and procedures increase. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

Until recently, the model for training new orthopaedic surgeons was referred to as “see one, do one, teach one”. Resident surgeons acquired their surgical skills by observing attending surgeons in the operating room and then attempted to replicate what they had observed on new patients, under the supervision of more experienced surgeons. Learning in the operating is an unideal environment to learn because it adds more time to surgical procedures and puts patients at an increased risk of having surgical errors occur during the procedure. Programs are slowly beginning to switch to a model that involves simulation-based training outside of the operating room. Wire navigation is one key skill in orthopaedics that has traditionally been difficult for programs to train on in a simulated environment. Our group has developed a radiation free wire navigation simulator to help train residents on this key skill. For simulation training to be fully adopted by the orthopaedic community, strong evidence that it is beneficial to a surgeon’s performance must first be established. The aim of this work is to examine how simulation training with the wire navigation simulator can be used to improve a resident’s wire navigation performance. The work also examines the metrics used to evaluate a resident’s performance in a simulated environment and in the operating room to understand which metrics best capture wire navigation performance. In the first study presented, simulation training is used to improve first year resident wire navigation performance in a mock operating room. The results of this study show that depending on how the training was implemented, residents were able to significantly reduce their tip-apex distance in comparison with a group that had received a simple didactic training. The study also showed that performance on the simulator was correlated with performance in this operating room. This study helps establish the transfer validity of the simulator, a key component in validating a simulation model. The second study presents a model for using the simulator as a platform on which a variety of wire navigation procedures could be developed. In this study, the simulator platform, originally intended for hip wire navigation, was extended and modified to train residents in placing a wire across the iliosacral joint. A pilot study was performed with six residents from the University of Iowa to show that this platform could be used for training the other applications and that it was accepted by the residents. The third study examined wire navigation performance in the operating room. In this study, a new metric of performance was developed that measures decision making errors made during a wire navigation procedure. This new metric was combined with the other metrics of wire navigation performance (tip-apex distance) into a composite score. The composite score was found to have a strong correlation (R squared = 0.79) with surgical experience. In the final study, the wire navigation simulator was taken to a national fracture course to collect data on a large sample of resident performance. Three groups were created in this study, a baseline group, a group that received training on the simulator, and a third group that observed the simulator training. The results of this study showed that the training could improve the overall score of the residents compared to the baseline group. The overall distribution from resident performance between groups also shows that a large portion of residents that did not receive training came in below what might be considered as competent performance. Further studies will evaluate how this training impacts performance in the operating room.

Articular fracture reduction is a complex surgical task that requires surgeons to be competent at multiple surgical skills to successfully complete. The list of skills needed includes the ability to use fluoroscopic images to build a 3D mental model of the fracture during reconstruction, the proper handling and use of surgical instruments, how to manipulate the fracture fragment into a reduced configuration with minimal hand motion, proper k-wire placement, and the preservation of surrounding soft tissues. Current training methodology is based on an apprenticeship model. The resident learns by watching a senior surgeon, and then preforms the procedure on live patients under the guidance of the senior surgeon to gain competence. This endangers the patient and does not provide the best outcome for either patient or resident. The work presented in this thesis is the early development of an articular fracture reduction simulator, the subsequent use of the simulator in the training of orthopaedic residents, and assessment of the improvement of residents after practice on the simulator. To date, the simulator has been tested on four different groups of residents,3 different groups from the University of Iowa and one group from the University of Minnesota. Considerable effort has been made to validate the improvement seen in resident performance through objective means. The Objective Structured Assessment of Technical Skills (OSATS) is a global rating score and procedural checklist that has been previously validated to objectively measure surgical skill. Other assessment metrics include hand motion capture to count the number of discrete actions and measure distance traveled during the surgical procedure, fluoroscopic usage and radiation exposure, articular `step-off', the surface deviation from an intact or ideal reconstruction, and contact stress exposure. The results indicate that the goals for the simulator have been met, that the simulator provides a means of training orthopaedic residents, assessing improvement, decreased the cost of training, and improved patient safety. The simulator is not without limitations including sample size, and radiation exposure. The task being trained is complex and can be broken down into basic subtasks that could be trained individually. Even with flaws, the simulator is an improvement over current training methods and is an excellent first step toward creating a surgical skills curriculum to comply with new mandates from orthopaedic surgery's governing bodies.

O aprendizado de cirurgia envolve inicialmente um conhecimento teórico seguido de um treinamento prático do aluno. Atividades em laboratório permitem ao aluno conhecer o instrumental cirúrgico e as dificuldades de técnica operatória antes de executar os procedimentos na clínica. Várias metodologias têm sido propostas no processo ensino-aprendizagem de cirurgia, mas tão importante quanto o método de ensino é a avaliação do aprendizado e a competência do aluno. Este trabalho teve como objetivo comparar três métodos diferentes de ensino de técnica cirúrgica, através de avaliações práticas utilizando um modelo que permite as manobras de incisão, divulsão e sutura. Trinta alunos sem conhecimento ou experiência prévia em cirurgia foram divididos em três grupos onde uma estratégia de ensinoaprendizagem diferente foi empregada: Grupo 1 - metodologia ativa, Grupo 2 - leitura prévia de texto e Grupo 3 - leitura prévia de texto com demonstração em vídeo. O conteúdo programático foi o mesmo para todos os grupos. Ao término dessa atividade, todos realizaram o procedimento estudado no modelo; os itens avaliados seguiram um checklist computando S para questões corretas e N para erradas e transformadas em notas de zero a dez. A avaliação no modelo foi repetida em 30 e 60 dias. Para verificar a diferença entre as médias das notas nos grupos foram aplicados procedimentos de análise de variância (ANOVA) e comparação múltipla pelo método de Tukey (nível de significância = 0,05). Os dados mostraram que a metodologia ativa (Grupo 1) apresentou melhores resultados com relação à assimilação imediata do conhecimento, seguida da que utilizou texto e vídeo (p=0,0004) e, por último, a leitura do texto (p=0,0001). Entretanto, essa metodologia também não foi totalmente efetiva na retenção do aprendizado da técnica. Baseado nas condições desse estudo, podemos concluir que apesar da metodologia ativa alcançar melhor desempenho inicial em relação às outras em todas as etapas, as três estratégias foram similares na manutenção do que foi aprendido em procedimentos cirúrgicos básicos após 60 dias. Repetições durante o aprendizado de habilidades manuais são essenciais para assimilação adequada. Avaliações constantes são fundamentais para conferir a evolução do aprendizado, permitindo reforço teórico e repetições do treinamento das habilidades práticas e direcionando para o tipo de metodologia mais indicada no momento. / Surgical learning initially involves theory understanding followed by surgical practice training. Laboratories activities allow the students introduction to special instruments and comprehension of operative technical difficulties before the use and execution on clinical working. Many methodologies have been proposed in teaching and learning of surgery practice but assessment of learning skills and abilities gained by the student is imperative. The present study was proposed to compare three different methodologies of teaching a basic surgical technique through a practical assessment employing a learning model that allows incision, divulsion and suture procedures. Thirty undergraduate students without any knowledge or previous surgical experience were divided in three groups (n=10) each one received a singular methodological learning strategy: Group 1 - interactive methodology, Group 2 - text reading only and Group 3 - text reading and demonstration video. Programmatic issue was the same for all groups. After matter and technical procedures were instructed by one of the strategies apprentices were allowed to execute in the learning model the procedure studied. A structured evaluation test taking to account correct or incorrect maneuvers was applied by a trained observer. Grades from 0-10 were given in each examination. Evaluation trial was repeated 30 and 60 days after the first class. Data from grades media between groups and periods were considering for statistical analysis by ANOVA and Tukey method (significant level = 0,05). The results showed that interactive methodology (Group 1) presented the best significant learning results in view of the immediately assimilation of procedure comprehension compared to group 3 (p=0,0004) that has used text reading and video and to group 2 (p=0,0001) that had read only the text. However, interactive methodology was not totally effective on maintenance of the learning skills. Based on the controlled conditions of this study, it was also possible to conclude that despite the fact that interactive learning methodology had demonstrated better initial learning results, the three strategies were similar on absorption of basic surgery procedures knowledge after 60 days. Repetition on learning a new manual ability is essential for assimilation. Evaluation tests to assess learning evolution are fundamental to check teaching strategies and to permit theory feedbacks and proficiency learning.

O aprendizado de cirurgia envolve inicialmente um conhecimento teórico seguido de um treinamento prático do aluno. Atividades em laboratório permitem ao aluno conhecer o instrumental cirúrgico e as dificuldades de técnica operatória antes de executar os procedimentos na clínica. Várias metodologias têm sido propostas no processo ensino-aprendizagem de cirurgia, mas tão importante quanto o método de ensino é a avaliação do aprendizado e a competência do aluno. Este trabalho teve como objetivo comparar três métodos diferentes de ensino de técnica cirúrgica, através de avaliações práticas utilizando um modelo que permite as manobras de incisão, divulsão e sutura. Trinta alunos sem conhecimento ou experiência prévia em cirurgia foram divididos em três grupos onde uma estratégia de ensinoaprendizagem diferente foi empregada: Grupo 1 - metodologia ativa, Grupo 2 - leitura prévia de texto e Grupo 3 - leitura prévia de texto com demonstração em vídeo. O conteúdo programático foi o mesmo para todos os grupos. Ao término dessa atividade, todos realizaram o procedimento estudado no modelo; os itens avaliados seguiram um checklist computando S para questões corretas e N para erradas e transformadas em notas de zero a dez. A avaliação no modelo foi repetida em 30 e 60 dias. Para verificar a diferença entre as médias das notas nos grupos foram aplicados procedimentos de análise de variância (ANOVA) e comparação múltipla pelo método de Tukey (nível de significância = 0,05). Os dados mostraram que a metodologia ativa (Grupo 1) apresentou melhores resultados com relação à assimilação imediata do conhecimento, seguida da que utilizou texto e vídeo (p=0,0004) e, por último, a leitura do texto (p=0,0001). Entretanto, essa metodologia também não foi totalmente efetiva na retenção do aprendizado da técnica. Baseado nas condições desse estudo, podemos concluir que apesar da metodologia ativa alcançar melhor desempenho inicial em relação às outras em todas as etapas, as três estratégias foram similares na manutenção do que foi aprendido em procedimentos cirúrgicos básicos após 60 dias. Repetições durante o aprendizado de habilidades manuais são essenciais para assimilação adequada. Avaliações constantes são fundamentais para conferir a evolução do aprendizado, permitindo reforço teórico e repetições do treinamento das habilidades práticas e direcionando para o tipo de metodologia mais indicada no momento. / Surgical learning initially involves theory understanding followed by surgical practice training. Laboratories activities allow the students introduction to special instruments and comprehension of operative technical difficulties before the use and execution on clinical working. Many methodologies have been proposed in teaching and learning of surgery practice but assessment of learning skills and abilities gained by the student is imperative. The present study was proposed to compare three different methodologies of teaching a basic surgical technique through a practical assessment employing a learning model that allows incision, divulsion and suture procedures. Thirty undergraduate students without any knowledge or previous surgical experience were divided in three groups (n=10) each one received a singular methodological learning strategy: Group 1 - interactive methodology, Group 2 - text reading only and Group 3 - text reading and demonstration video. Programmatic issue was the same for all groups. After matter and technical procedures were instructed by one of the strategies apprentices were allowed to execute in the learning model the procedure studied. A structured evaluation test taking to account correct or incorrect maneuvers was applied by a trained observer. Grades from 0-10 were given in each examination. Evaluation trial was repeated 30 and 60 days after the first class. Data from grades media between groups and periods were considering for statistical analysis by ANOVA and Tukey method (significant level = 0,05). The results showed that interactive methodology (Group 1) presented the best significant learning results in view of the immediately assimilation of procedure comprehension compared to group 3 (p=0,0004) that has used text reading and video and to group 2 (p=0,0001) that had read only the text. However, interactive methodology was not totally effective on maintenance of the learning skills. Based on the controlled conditions of this study, it was also possible to conclude that despite the fact that interactive learning methodology had demonstrated better initial learning results, the three strategies were similar on absorption of basic surgery procedures knowledge after 60 days. Repetition on learning a new manual ability is essential for assimilation. Evaluation tests to assess learning evolution are fundamental to check teaching strategies and to permit theory feedbacks and proficiency learning.

No description available.

<p>Training and ergonomics evaluation for laparoscopic surgery is an important tool for the assessment of trainees. Timely and objective assessment helps surgeons improve hand dexterity and movement precision, and perform surgery in an ergonomic manner. Traditionally, skill is evaluated by expert surgeons observing trainees, but this approach is both expensive and subjective. The approach proposed by this research employs an Ascension 3DGuidance trakSTAR system that captures the positions and orientations of hand and laparoscopic tool trajectories. Recorded trajectories are automatically analysed to extract meaningful feedback for training evaluation using statistical and machine learning methods.</p> <p>The data are acquired while a subject performs a standardized task such as peg transfer or suturing. The system records laproscopic instrument positions, hand, forearms, elbows trajectories, as well as wrist angles. We propose several metrics that attempt to objectively quantify the skill level or ergonomics of the procedure. The metrics for surgical skills are based on surgical instrument tip trajectories, whereas the ergonomics metric uses wrist angles. These metrics have been developed using statistical and machine learning methods.</p> <p>The metrics have been experimentally evaluated by using a population of seven first year postgraduate urology residents, one general surgery resident, and eight fourth year postgraduate urology residents and fellows. The machine learning approach discriminated correctly in 73% of cases between experts and novices. The machine learning approach applied to ergonomics data correctly discriminates between experts and novices in 88% of the cases for the peg transfer task and 75% for the suturing task. We also propose a method to derive a competency-based score using either statistical or machine learning derived metrics.</p> <p>Initial experimental data show that the proposed methods discriminate between the skills and ergonomics of expert and novice surgeons. The proposed system can be a valuable tool for research and training evaluation in laparoscopic surgery.</p> / Master of Applied Science (MASc)