Noriyuki Matsuoka

Towards understanding the suture/ligature skills during the training process using WKS-2RII

ObjectNowadays, most of the surgical training programs follow a duration-based format that focuses on improving technical skills of trainees for a fixed amount of time before declaring their proficiency. More recently, different approaches have been proposed for the skills assessment; such as the objective structured clinical examination (OSCE). The OSCE consists of different stations in which trainees are required to perform practical exams while their performance is evaluated by examiners. However, their performance cannot be easily assessed by the simple observation of the task. As a result, no standard evaluation criteria can be conceived.MethodsThanks to the recent advances in Robot Technology (RT); more efficient training systems can be conceived. In particular, authors believe in the importance of developing automated training devices designed to provide training progress quantitative information of trainees. For this reason, at Waseda University, since 2004, we have proposed as a long-term research goal, the development of a Patient Robot which nearly reproduces the human body anatomy and physiology by embedding sensors and actuators into a human model. Due to the complexity of patient robot development, as a first approach, we have proposed the development of a Suture/Ligature Training System. In this paper, the details of Waseda-Kyotokagaku Suture No. 2 Refined II (WKS-2RII) are presented. The WKS-2RII has been designed to reproduce the task conditions of the suture and ligature as well as to provide quantitative information of artificial skin movement, and the physical properties of the suture. From such collected data, we have proposed an Evaluation Function that integrates all the proposed evaluation parameters.ResultsIn order to verify the effectiveness of the WKS-2RII, a set of experiments were proposed to analyze the performance of subjects while performing the task with the WKS-2RII. The experiments were designed to determine if the proposed system may provide more detailed information of the task in a quantitative way. From the experimental results, we have confirmed that the WKS-2RII is capable of providing quantitative assessment of the task. In contrast to the conventional training methods (i.e., OSCE, etc.), the WKS-2RII can provide more detailed information of the task performance, so that the proposed system can detect the differences among different level of expertise (five surgeons, five medical students and five unskilled persons) as well as detect improvements of trainees by plotting the learning curve.ConclusionsIn this paper, we have presented the improvements on the WKS-2RII and a unique evaluation function has been proposed. Regarding the weighting coefficients, the discriminant analysis method was used to determine the optimal values of the weighting coefficients.

Quantitative assessment of the surgical training methods with the suture/ligature training system WKS-2RII

The emerging field of medical robotics is aiming in introducing intelligent tools to perform medical procedures. In particular, robotic researchers have been proposed advanced medical training systems to enhance motor dexterities of trainees. An efficient medical training system should be designed to simulate real-world conditions and to assure their effectiveness as the representation of the motor skills often differs among trainees. Up to now, several training simulators have been developed by medical companies designed to reproduce with high fidelity the human body. However, such devices are not designed to provide any information to trainees. Therefore, we have proposed the development of a Patient Robot which embeds sensors and actuators into a conventional human model. Due to its complexity, as a first approach; we are presenting the development of a suture training system designed to simulate the real-world task conditions as well as providing quantitative assessments. In particular; the Waseda-Kyotokagaku Suture No.2 Refined II is presented, which includes a new evaluation function to provide more detailed information of the task. A set of experiments were proposed to analyze the performance of trainees. From the experimental results, we could confirm its effectiveness to detect differences of the performance of trainees.

Development of a sensor system towards the acquisition of quantitative information of the training progress of surgical skills

Up to now, there is no widely accepted assessment of surgical skills. Nowadays, an objective structured clinical examination (OSCE) has been proposed as a modern type of examination often used in medicine to test skills. The assessment of skills is realized by practical exams, in which students are evaluated by experienced examiner using a check list. However, the examiner lacks of information which cannot be obtained through the simple observation of the task. Therefore, at Waseda University, we have proposed the development of a patient robot as an advanced evaluation tool to provide more detailed information of the task. As a first approach of our long-term research target, we have proposed the development of a suture/ligature training system which provides quantitative information of the movement of a dummy skin as well as information of the quality of task. Therefore in this paper, we are presenting the Waseda Kyotokagaku Suture No. 2 Refined II (WKS-2RII). The WKS-2RII has been designed to provide more detailed information of the task performance. Experiments were proposed to confirm the effectiveness of the proposed evaluation parameters to distinguish the differences among different training methods.

An Endoscopic Surgical Skill Validation System for Pediatric Surgeons Using a Model of Congenital Diaphragmatic Hernia Repair

PURPOSE We developed a system to objectively verify the endoscopic surgical skills of pediatric surgeons. MATERIALS AND METHODS We developed a thoracoscopic model of congenital diaphragmatic hernia mimicking a newborns size. The examinees were divided into Experts (n = 10) and Trainees (n = 19), and each group performed two tasks (Task 1, reduction of a herniated intestine from the thoracic space to the abdomen; Task 2, perform three suture ligatures of a diaphragm defect using intracorporeal knot-tying). The end points were the time required to complete Task 1, time score calculated using the residual time from the time limit for Task 2, number of complete full-thickness sutures, maximum air-pressure tolerance, degree of diaphragm deformation, and the residual defect areas after suturing. We also evaluated the total path length and velocity of the forceps tips using a three-dimensional position measurement instrument. RESULTS The Experts had significantly superior results for the time for Task 1, time score, number of complete full-thickness sutures, maximum air-pressure tolerance, and degree of diaphragm deformation in Task 2 (all P < .05). We found that the total path length and average velocities for the left forceps were inferior to those of the right forceps in both tasks in the Trainees (both P < .05, respectively), whereas the Expert group showed no significant laterality in these tasks. CONCLUSIONS Our model could validate the quality of endoscopic surgical skills and could differentiate between Expert and Trainee pediatric surgeons. The Experts could use their forceps equally well to perform tasks even in a small working space.

Integration of an evaluation function into the suture/ligature training system WKS-2R

Up to now, there is no widely accepted quantitative evaluation scheme. Nowadays, an objective structured clinical examination has been proposed as a modern type of examination often used in medicine to test skills such as medical procedures, etc. The assessment of skills is realized by practical exams, in which students are evaluated by experienced examiner using a check list. However, the examiner lacks of information which cannot be obtained trough the simple observation of the task. Thanks to the advances in robot technology in embedded systems, etc.; more advanced evaluation tools can be conceived. For this reason, at Waseda University, we have proposed the development of a patient robot as an advanced evaluation tool to provide more detailed information of the task. As a first approach of our long-term research target, we have proposed the development of a suture/ligature training system which provides quantitative information of the movement of a dummy skin as well as information of the quality of task. In this paper; we describe the functionalities of the newest version, the Waseda-KyotoKagaku Skin No.2 Refined (WKS-2R), which has been designed to provide quantitative information of the task. In addition, we are proposing a new evaluation function which includes performance indexes and weighting coefficients. As a first approach, the weighting coefficients were determined by using the discriminant analysis. A set of experiments were proposed to confirm the effectiveness of the proposed evaluation function. From the preliminary results, the evaluation function was useful in detecting differences among different levels of expertise as well as detecting improvements during the training process by computing the learning curve.

Development of a head robot with facial expression for training on neurological disorders

Neurological examinations are among the most important clinical skills to identify disorders in the neurological system at early stages. Training on neurological examination for inexperienced doctors plays an important role in improving accuracy of diagnosis. Such training programs have been conducted until now using physical simulators or simulated patients (SPs). However, conventional simulators can simulate only facial features of patients and not their responses or motions. SP cannot simulate them either. We have therefore been developing a whole-body patient robot named WKP(Waseda Kyotokagaku Patient robot) for training on neurological examination. The main advantage of WKP over conventional simulators and SPs is its ability to simulate motions and responses of patients having disorders in their neurological systems. We then developed a head humanoid with facial expression for training on neurological disorders as a part of WKP. This humanoid is equipped with 21 degrees of freedom; it has 2 liquid crystal panels with lenses, and simulates facial movements with imitating the wrinkles and eyeball movements of patients with disorders in their cranial nerves. We then performed a set of experiments to validate the head humanoid. The main focus of this paper is on mechanical design and performance verification of the head humanoid.

Board 549- Technology Innovations Abstract A New Objective Assessment System of the Suture Ligature Method of the Intestinal Anastomosis Model for Laparoscopic Surgery (Submission #856)

Introduction/Background Various training simulators for laparoscopic surgery skills have been developed, such as virtual reality simulators and box trainers. Surgical skills are typically evaluated by measuring the path lengths of the tips of the operative instruments using three-dimensional tracking sensors. Experienced surgeons are generally able to perform tasks with shorter path lengths and time than inexperienced operators.1,2 However, there is no method of assessing laparoscopic surgery skills designed to specifically assess the suture ligature method, which provides a quantitative result based on the clinical condition. The purpose of this study was to develop a new objective assessment system of the suture ligature method of the intestinal anastomosis model for laparoscopic surgery. In this study, we evaluated objective suturing skill using this system. Methods Materials & Methods: Sixteen doctors who had each performed over 100 laparoscopic surgeries (expert group) and 23 medical students who had no experience of laparoscopic surgery (novice group) were enrolled in this study. The novice group practiced a suturing method to successfully perform three suture ligatures before this experiment. The new assessment system consists of a new artificial intestinal model, which has an intestine-like structure, and a pressure measurement device. The artificial intestinal model consists of four layers, including the mucosal layer, submucosal layer, muscle layer, and serosal layer. Suturing skill was evaluated by internal air pressure of the model. The model has a ten mm size wound at the center. The examinees performed a suturing task using the artificial model with a box trainer. We compared the number of stitches, the performance time, and the internal air pressure between both groups, and examined the similarity of the model to the intestine by a questionnaire given to only the expert group because the novice group had no clinical experience. We analyzed the data and evaluated acceptable values for the skill assessment task in this system. Results for the expert and novice groups were compared using the Student’s t-test. A p value <0.05 was defined as statistically significant. Results: Table 1 shows the Results of the comparisons between the expert group and the novice group. The similarity of the model to the intestine was 71.9%. The appropriate values of the number of stitches, the performance time, and the internal air pressure were three stitches, 417 s, and 5.20 [kPa], respectively, because maximum differences were found between the expert group and novice group under the condition of three stiches. Table 1 Comparison of Results between the expert and novice groups Results: Conclusion Our objective system is useful for assessing suturing skill in laparoscopic surgery in a quantitative manner. References 1. Verdaasdonk EGG, Dankelman J, Lange JF, Stassen LPS. Transfer validity of laparoscopic knot-tying training on a VR simulator to a realistic environment: a randomized controlled trial. Surgical endoscopy. 2008;22(7):1636-42. 2. Hofstad EF, Våpenstad C, Chmarra MK, Langø T, Kuhry E, Mårvik R. A study of psychomotor skills in minimally invasive surgery: what differentiates expert and nonexpert performance. Surgical endoscopy. 2013;27(3):854-63. Disclosures None.