A Low Mean Closing Load and a Decrease in Load Change at the Tip Increase the Comfort of Scissors.

Introduction During surgery, surgeons intuitively recognize when they are using dull scissors and find them difficult to use. The purpose of this study was to objectively evaluate the physical characteristics of scissors and the comfort reported by surgeons to develop objective quality control standards for scissors used in surgery. Methods Sensory and measurement tests were conducted to evaluate the comfort and physical characteristics of ten pairs of Cooper scissors. As a sensory test, thirty-one volunteer surgeons opened and closed the scissors and selected three that felt comfortable and three that were uncomfortable. The results were scored. For measurement, a load was applied to the handle of the scissors. The load pressure and displacement of the width between each handle when the scissors were closed were measured. Results A strong negative correlation was found between the total comfort score and the mean load value between sensory and measurement tests (r=-0.717, p=0.0195). The correlation between the total score and the change in load at the tip showed a moderate negative correlation (r=-0.687, p=0.0282). Multiple regression analysis showed that the change in load at the tip was an independent factor affecting the total score. Conclusions Surgeons consider scissors with a low mean load required to close the scissors and a small change in load at the tip to be comfortable. The mean load on scissors and the change in load at the tip should be considered in the development of quality control standards for scissors used in surgery.

Evaluation of Scissor Glide Characteristics Through Surgeons' Subjective Assessment: The Application of Nitriding in Scissor Hardening Tests.

INTRODUCTION: In robotic surgery, studies on providing tactile feedback to users are ongoing. However, the accuracy of the subjective sensations of surgeons, as users, has been largely unassessed. This study aimed to assess the validity of surgeons' subjective evaluations of scissors resistance through interindividual, inter-surgeon, and objective evaluations. Furthermore, in this study, we explored the possibility of using nitriding to increase the hardness of the scissors and assessed changes in subjective resistance values before and after nitriding using this approach. METHOD: Five surgeons conducted validation of five curved surgical scissors (145 mm; Arakawa Seisakujyo Co., Ltd., Tokyo, Japan) and assessed their subjective resistance using a scale from 0 to 10, where a rating of 10 signified significant resistance impeding the scissors' closure. The temporal changes in subjective resistance values, from maximum open to close, were graphically recorded. To demonstrate the reproducibility of subjective resistance values, the subjective resistance values of the same control scissors were measured at intervals of at least two weeks, and the correlation coefficient was calculated. To analyze the closing characteristics of subjective resistance values between different pairs of scissors, the effect of scissor type and scissor closure position was compared as two independent variables using a two-factor analysis of variance. A comparative evaluation was conducted to assess the frictional properties of scissors after nitriding, comparing the subjective assessment by surgeons with the objective assessment using a digital force gauge. RESULTS: The correlation coefficient of subjective resistance values measured by surgeons demonstrated a high reproducibility of 0.746. A two-factor analysis of variance conducted on subjective resistance values demonstrated the presence of a primary effect for the sample factor (scissors), as well as for the position factor (closing process), with the additional observation of the interaction between these two factors. The results from the two-factor analysis of variance above provide evidence supporting the validity of the subjective resistance measurements. There was a significant increase in subjective resistance after the nitriding process. The graph of subjective resistance values and objective resistance values showed similarity. CONCLUSIONS: The surgeons' subjective assessment of scissors resistance showed high reproducibility and validity, as evidenced by distinguishable differences in scissor movement interactions and pre- and post-nitriding resistance. Further studies are warranted to expand on these findings.

Attempt to extract features and classify subjective poor physical conditions in facial images using deep metric learning.

With the spread of COVID-19, the need for remote detection of physical conditions is increasing, for example, there are several situations wherein the body temperature has to be measured remotely to detect febrile individuals. Aiming to remotely detect physical conditions, the study attempted to investigate anomaly detection based on facial color and skin temperature, which are indicators related to hemodynamics. Triplet loss was used to extract features related to subjective health feelings from facial images to evaluate whether there is a relationship between subjective health feelings and facial images. A classification of subjective health feelings related to poor physical conditions based on these features was also attempted. To obtain the data, an experiment was conducted for approximately 1 year to measure facial visual and thermal images, and subjective feelings related to physical conditions. Anomaly levels were defined based on subjective health feelings. Anomaly detection models were constructed by classifying anomaly and normal data based on subjective health feelings. Facial visible and thermal images were applied to the trained model to quantitatively evaluate the accuracy of the classification of anomaly conditions related to subjective health. At higher levels of anomaly, a combination of facial visible and thermal images resulted in the classification of subjective health feelings with moderate accuracy. Further, the results suggest that the eyes and sides of the nose may indicate subjective health feelings.

An online feedback system for laparoscopic training during the COVID-19 pandemic: evaluation from the trainer perspective.

Objective: A system to provide feedback for laparoscopic training using an online conferencing system during the COVID-19 pandemic was developed. The purpose of this study is to evaluate this system from the trainer perspective. Design: A procedural feedback system using an online conferencing system was devised. Setting: Surgical training was observed using an online conferencing system (Zoom). Feedback was provided while viewing suture videos which are, as a feature of this system, pre-recorded. Feedback was then recorded. Trainer comments were then converted into text, summarized as feedback items, and sorted by suture phase which facilitates reflection. Trainers completed a questionnaire concerning the usability of the online feedback session. Results: Eleven trainers were selected. Physicians had an average experience of 21.9 ± 5.9 years (mean ± standard deviation). The total number of feedback items obtained by classifying each phase was 32. Based on questionnaire results, 91% of trainers were accustomed to the use of Zoom, and 100% felt that online procedural education was useful. In questions regarding system effectiveness, more than 70% of trainers answered positively to all questions, and in questions about efficiency, more than 70% of trainers answered positively. Only 55% of the trainers felt that this system was easy to use, but 91% were satisfied as trainers. Conclusions: The results of the questionnaire suggest that this system has high usability for training. This online system could be a useful tool for providing feedback in situations where face-to-face education is difficult.

Laparoscopic surgical skill evaluation with motion capture and eyeglass gaze cameras: A pilot study.

INTRODUCTION: An eyeglass gaze camera and a skeletal coordinate camera without sensors attached to the operator's body were used to monitor gaze and movement during a simulated surgical procedure. These new devices have the potential to change skill assessment for laparoscopic surgery. The suitability of these devices for skill assessment was investigated. MATERIAL AND METHODS: Six medical students, six intermediate surgeons, and four experts performed suturing tasks in a dry box. The tip positions of the instruments were identified from video recordings. Performance was evaluated based on instrument movement, gaze, and skeletal coordination. RESULTS: Task performance time and skeletal coordinates were not significantly different among skill levels. The total movement distance of the right instrument was significantly different depending on the skill level. The SD of the gaze coordinates was significantly different depending on skill level and was less for experts. The expert's gaze stayed in a small area with little blurring. CONCLUSIONS: The SD of gaze point coordinates correlates with laparoscopic surgical skill level. These devices may facilitate objective intraoperative skill evaluation in future studies.

SAFETY AND EFFECTIVENESS OF A STATIC WEARABLE CHAIR FOR PATIENTS REQUIRING REHABILITATION: A PRELIMINARY REPORT.

OBJECTIVE: To evaluate the acceptability of using a static wearable chair for patients requiring rehabilitation. METHODS: The acceptability of use of a static wearable chair during rehabilitation was assessed via static balance and subjective evaluation of 7 healthy subjects and 3 patients during standing training. Participants performed 1 standing task in free mode (in which the knee could bend freely) and 1 in support mode (in which the user could sit on the wearable chair with the knee slightly bent) for 3 min. For balance evaluation, the skeletal coordinates were measured. For subjective evaluation, a visual analogue scale questionnaire was administered before and after each task. RESULTS: Balance assessment revealed that patients had less head sway during support, whereas subjective evaluation showed that the device support created a positive psychological state in terms of stability, comfort, satisfaction, interest in usage, and motivation for rehabilitation. However, patients reported feeling strangeness, fear, or restraint during support. CONCLUSION: The static wearable chair improved the static balance of 3 patients and created a more positive psychological state. Use of the device is considered acceptable for use with rehabilitation patients. However, patients might feel strangeness, fear, and restraint during support. Familiarization with the static wearable chair may make it more acceptable among rehabilitation patients.

An attempt to construct the individual model of daily facial skin temperature using variational autoencoder.

Facial skin temperature (FST) has also gained prominence as an indicator for detecting anomalies such as fever due to the COVID-19. When FST is used for engineering applications, it is enough to be able to recognize normal. We are also focusing on research to detect some anomaly in FST. In a previous study, it was confirmed that abnormal and normal conditions could be separated based on FST by using a variational autoencoder (VAE), a deep generative model. However, the simulations so far have been a far cry from reality. In this study, normal FST with a diurnal variation component was defined as a normal state, and a model of normal FST in daily life was individually reconstructed using VAE. Using the constructed model, the anomaly detection performance was evaluated by applying the Hotelling theory. As a result, the area under the curve (AUC) value in ROC analysis was confirmed to be 0.89 to 1.00 in two subjects.

Years of experience is more effective in defining experts in the gaze analysis of laparoscopic suturing task than task duration.

In this study, the relationship between gaze patterns, task duration, and years of experience, which are commonly used to define and evaluate expert surgeons in laparoscopic surgery, was identified. Ten surgeons with 1-28 years of experience and six inexperienced students were included. Subjects used forceps to repeat the task of suturing a suture pad. Each subject wore an eye-marking recorder, and gaze points were recorded and analyzed. No significant relationship between task duration and gaze pattern was observed. However, there was a significant relationship between a surgeon's years of experience and the percentage of time spent gazing at the forceps. Subjects with more years of experience operated without looking at the forceps and fixed their gaze on the operational target. Therefore, when analyzing laparoscopic gazing patterns, it may be more appropriate to define an "expert" based on the years of experience rather than task duration.

Face Alignment in Thermal Infrared Images Using Cascaded Shape Regression.

The evaluation of physiological and psychological states using thermal infrared images is based on the skin temperature of specific regions of interest, such as the nose, mouth, and cheeks. To extract the skin temperature of the region of interest, face alignment in thermal infrared images is necessary. To date, the Active Appearance Model (AAM) has been used for face alignment in thermal infrared images. However, computation using this method is costly, and it has a low real-time performance. Conversely, face alignment of visible images using Cascaded Shape Regression (CSR) has been reported to have high real-time performance. However, no studies have been reported on face alignment in thermal infrared images using CSR. Therefore, the objective of this study was to verify the speed and robustness of face alignment in thermal infrared images using CSR. The results suggest that face alignment using CSR is more robust and computationally faster than AAM.

Functional innervation of human induced pluripotent stem cell-derived cardiomyocytes by co-culture with sympathetic neurons developed using a microtunnel technique.

Microelectrode array (MEA) based-drug screening with human induced pluripotent stem cell-derived cardiomyocytes (hiPSCM) is a potent pre-clinical assay for efficiently assessing proarrhythmic risks in new candidates. Furthermore, predicting sympathetic modulation of the proarrhythmic side-effects is an important issue. Although we have previously developed an MEA-based co-culture system of rat primary cardiomyocyte and sympathetic neurons (rSNs), it is unclear if this co-culture approach is applicable to develop and investigate sympathetic innervation of hiPSCMs. In this study, we developed a co-culture of rSNs and hiPSCMs on MEA substrate, and assessed functional connections. The inter-beat interval of hiPSCM was significantly shortened by stimulation in SNs depending on frequency and pulse number, indicating functional connections between rSNs and hiPSCM and the dependency of chronotropic effects on rSN activity pattern. These results suggest that our co-culture approach can evaluate sympathetic effects on hiPSCMs and would be a useful tool for assessing sympathetic modulated-cardiotoxicity in human cardiac tissue.

A device for co-culturing autonomic neurons and cardiomyocytes using micro-fabrication techniques.

It is still unclear how the activity of sympathetic and parasympathetic neurons influences the activity of cardiomyocytes in culture. We developed a device for co-culturing sympathetic neurons, parasympathetic neurons, and cardiomyocytes using micro-fabrication techniques. Morphological connections between each type of autonomic neuron and the cardiomyocytes were observed by immunostaining. The inter-beat-interval (IBI) of the cardiomyocytes was modulated after electrically stimulating each type of autonomic neuron. Modulation of the IBI was blocked by the addition of pharmacological blockers to the culture medium. These results suggest that the co-culture device can be utilized to understand how the activity of sympathetic neurons and parasympathetic neurons influences the activity of cardiomyocytes in the culture environment.