Kazuyuki Hatake

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.

Development of the evaluation system for the Airway Management Training System WKA-1R

The emerging field of medical robotics is aiming in introducing intelligent tools. More recently, thanks to the innovations on robot technology (RT), advanced medical training systems have been introduced to improve the skills of trainees. The principal challenges of developing efficient medical training systems are simulating real-world conditions and assuring their effectiveness. Up to now, different kinds of medical training devices have been developed which are designed to reproduce with high fidelity the human anatomy. Due to their design concept, the evaluation of progress of the trainees is based on subjective assessments limiting the understanding of their effectiveness. In this paper, we are presenting our research towards developing a patient robot designed to simulate the real-world task conditions and providing objective assessments of the training achievements. Due to its complexity; in this paper, we are presenting as a first approach the development of the Waseda-Kyotokagaku Airway No. 1R (WKA-1R) which includes a human patient model with embedded sensors in order to provide objective assessments of the training progress. In particular, we have proposed an evaluation function to quantitatively evaluate the task performance by determining the weighting of coefficients. In order to determine the weighting of coefficients, we applied discriminant analysis. In order to determine the effectiveness of the proposed evaluation function to detect differences among different levels of expertise, an experimental setup was carried out. From the experimental results, we could find a significant difference between both groups (P < 0.05).

Development of Patient Scenario Generation which can reproduce characteristics of the patient for simulating real-world conditions of task for airway management training system WKA-3

Recently, in medical field, different training methods for medical staff have been proposed. However, the lack of knowledge on the real improvements of trainees makes difficult the real effectiveness of those proposed methods. Therefore, we are proposing an Active Training system for the effective medical training. The Active training system is characterized by providing quantitative information of the trainees performance of the task to the trainee, simulating real-world conditions of the task, and assuring training effectiveness. In order to fulfill each of these characteristics, we have developed Waseda Kyotokagaku Airway No.3 (WKA-3) which makes it possible to obtain quantitative information for the trainees performance and reproduce the various cases, individual differences for the airway difficulties for the simulating real-world conditions of the task. In this paper, we are proposing a patient scenario generation which can reproduce the characteristics of the patient simulating real-world conditions of the task for WKA-3. In emergent situation or surgical operation, the characteristics of patients are presented in the three parameters such as: patient initial conditions, time variant status change, and reflex action. By adjusting, and combining each of the three parameters, we can reproduce the various patient scenarios. In this paper, we also state how to generate the Patient Scenario Generation using the position control and virtual compliance control. Finally, a set of experiments has been carried out to the doctor subjects in order to verify effectiveness of the proposed Patient Scenario Generation, and discuss the doctors about the result of the experiments.

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 the airway management training system WKA-2 designed to reproduce different cases of difficult airway

The emerging field of medical robotics aims to introduce intelligent tools to assist a physician. The main challenges for developing efficient medical robotic training systems are simulating real-world conditions of the task and assuring training effectiveness. High anatomic fidelity has been achieved in current systems. However, those training systems are designed to reproduce specific conditions of the task (passive training). In this research, we are focusing in developing an airway management training systems designed to reproduce various cases of difficult airway. Such difficulties (i.e. restricted mouth opening, various shapes of oral cavity including tongue swallowing, etc) may provoke traumas on different organs of the patient during an emergency situation. For this purpose, the authors have proposed the development of more advanced training tools. For this purpose, we have focused in embedding sensors and actuators to a conventional patient model towards the development of a patient robot (in previous research, authors have presented the evaluation model which embeds sensors). In this paper, we present an airway training system which embeds actuators into a mannequin. In particular, the mechanism design of the Waseda Kyotokagaku Airway No.2 (WKA-2) is detailed. The WKA-2 is composed of twelve active and one passive degrees of freedom; which are designed to reproduce the various cases of difficult airway. For this purpose, the WKA-2 reproduces the human muscles around the upper airway based on a wire driving mechanisms (a total of sixteen wires are used). In particular, the head of the model is composed of a tongue and mandible with translational and rotational movements around kinematic axis. In addition, we present the details of the kinematic model of WKA-2 which enable the robot to reproduce the airway difficulties. Finally, we presented the design of a tension sensor designed to measure the applied tension on each of the wire driving mechanism of WKA-2. As preliminary experiments, we reproduce several cases of difficult airways using WKA-2.

Development of a 3D simulation which can provide better understanding of trainee's performance of the task using airway management training system WKA-1RII

In the development of medical skill training systems, the efficiency of the system and the provision of quantitative feedback information to the trainee are very important. Furthermore, usage of the simulated operation platform should be as realistic as possible. In order to satisfy these requirements, we developed a robot to be used for airway management training: Waseda KyotoKagaku Airway No.1 Refined RII (WKA-1RII) (Fig. 1). In addition to realistically shaped hardware and various sensory equipments inside the robot, the new training system also uses a binocular vision system, an inertial measurement unit and a 3D simulation software component to track the movements of the trainee. For fully estimating the skills of the trainee and providing richer feedback, it is not enough to only use information about the tools movements from the inside of the robot. Therefore, we propose a system to fuse the sensory information from inside the robot with data from 3d vision and from the inertial measurement unit. This accurate information about the movements of the trainee is used to model the progress of the training with a 3d computer graphics simulator. The trainee can use this visualization during or after the training procedure to verify his training status. Using this system he has the possibility to easily compare his performance with a guideline performance provided by an experienced surgeon. In this paper we show a first conceptual application of this approach. The experimental results lead to the consideration that the approach is worth following in further research.

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.

Development of a novel flow sensor to acquire quantitative information on BVM operation during airway management training

Airway management is a basic skill for emergency rescue. The operation of the bag valve mask (BVM) is also a key process. The BVM is used not only to provide oxygen but also to detect if the tracheal tube is inserted in the trachea or bronchus. Currently, there are many training platforms designed for training medical staff. Most of them can provide subjective assessments. However, they are limited in providing quantitative assessments of a trainees performance, including information about the BVM operation. Therefore, we propose a novel flow sensor system that can not only provide quantitative information on the trainees BVM operation, but it can also objectively evaluate the trainees performance. Waseda Kyotokagaku Airway — No.5 (WKA-5) is the newest platform that we designed for airway management training. It is based on robot technologies. Many types of sensors are embedded in this robot. In this paper, we will introduce the mechanical structure of the flow sensor and the method of data processing. The flow sensor has superior characteristics, such as high precision, quick responsiveness, and ease of maintenance. Using this sensor, we can analyze the frequency of BVM operation and detect whether the tracheal tube is in the proper position. Finally, several preliminary experiments have been carried out to confirm the accuracy and effectiveness of the flow sensor and evaluate the trainees operation.

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 the airway management training system WKA-4: For improved high-fidelity reproduction of real patient conditions, and improved tongue and mandible mechanisms

In recent years advanced robotic technology has seen more use in the medical field to assist in the development of efficient training systems. Such training systems must fulfill the following criteria: they must provide quantitative information, must simulate the real-world conditions of the task, and assure training effectiveness. We developed Waseda Kyotokagaku Airway series to fulfill all of those requirements. The WKA series we had developed does not consider external appearance such as patient skin, or internal appearance such as the pharynx, larynx, and esophagus. Moreover, the tongue mechanism of the previous system can not precisely measure the force applied by medical devices and cannot simulate muscle stiffness. In addition, the mandible mechanism of the previous system could not adequately reproduce various airway difficulties or apply force control. For these reasons, we propose the WKA-4, which has high-fidelity simulated human anatomy, and we have improved the mechanism over the previous system. We have also attached a lung to the proposed system to improve simulation of the real-world conditions of the task. In this paper, we present how to design several organs with various embedded sensors and actuators, for a conventional patient model with high-fidelity simulated human anatomy. We also present the control system for the WKA-4. Finally, we present a set of experiments carried out using doctors as subjects, and they gave their valuable opinions about our system.