Objective psychomotor laparoscopic skills evaluation using a low-cost wearable device based on accelerometry: construct and concurrent validity study.

BACKGROUND: Motion analysis of surgical maneuvers provides useful quantitative information for the objective evaluation of the surgeons. However, surgical simulation laboratories for laparoscopic training do not usually integrate devices that help quantify the level of skills of the surgeons due to their limited resources and the high costs of new technologies. The purpose of this study is to present the construct and concurrent validity of a low-cost motion tracking system, based on a wireless triaxial accelerometer, employed to objectively evaluate psychomotor skills of surgeons during laparoscopic training. METHODS: An accelerometry system, a wireless three-axis accelerometer with appearance of wristwatch, was placed on the dominant hand of the surgeons to register the motion during the laparoscopy practice with the EndoViS simulator, which simultaneously recorded the motion of the laparoscopic needle driver. This study included the participation of 30 surgeons (6 experts, 14 intermediates and 10 novices) who performed the task of intracorporeal knot-tying suture. Using 11 motion analysis parameters (MAPs), the performance of each participant was assessed. Subsequently, the scores of the three groups of surgeons were statistically analyzed. In addition, a validity study was conducted comparing the metrics between the accelerometry-tracking system and the EndoViS hybrid simulator. RESULTS: Construct validity was achieved for 8 of the 11 metrics examined with the accelerometry system. Concurrent validity demonstrated that there is a strong correlation between the results of the accelerometry system and the EndoViS simulator in 9 of 11 parameters, showing reliability of the accelerometry system as an objective evaluation method. CONCLUSION: The accelerometry system was successfully validated. This method is potentially useful to complement the objective evaluation of surgeons during laparoscopic practice in training environments such as box-trainers and simulators.

Construct validity of the SurgForce system for objective assessment of laparoscopic suturing skills.

BACKGROUND: Laparoscopic surgery requires a new set of skill to be learned by the surgeons, of which the most relevant is tissue manipulation. Excessive forces applied to the tissue can cause rupture during manipulation or ischemia when confronting both sides of the tissue. The aim of this study is to establish the construct validity of the SurgForce system for objective assessment of advanced laparoscopic skills, based on the force signal generated during suture tasks, and the development of force parameters for evaluating tissue handling interaction. METHODS: The SurgForce system, a tissue handling training device that measures dynamic force, was used to capture the force generated by surgeons with different levels of laparoscopic experience. For construct validity, 37 participants were enrolled in this study: 19 medical students, 12 residents of surgical specialties and 6 expert surgeons. All participants performed an intracorporeal knotting suture task over a synthetic tissue pad with a laparoscopic box-trainer. The force performance of the participants was analyzed using 11 force-based parameters with the application of the SurgForce system. Statistical analysis was performed between novice, intermediate, and expert groups using a Kruskal-Wallis test, and between the pairs of groups using a Mann-Whitney U-test. RESULTS: Overall, 9 of the 11 force-related parameters showed significant differences between the three study groups. Results between the pairs of groups presented significant differences in 5 force parameters proposed. Construct validity results demonstrated that the SurgForce system was able to differentiate force performance between surgeons with different levels of laparoscopic experience. CONCLUSION: The SurgForce system was successfully validated. This force system showed its potential to measure the force exerted on tissue for objective assessment of tissue handling skills in suturing tasks. Furthermore, its compact design allows the use of this device in conventional laparoscopic box-trainers.

Development of a Laparoscopic Box Trainer Based on Open Source Hardware and Artificial Intelligence for Objective Assessment of Surgical Psychomotor Skills.

BACKGROUND: A trainer for online laparoscopic surgical skills assessment based on the performance of experts and nonexperts is presented. The system uses computer vision, augmented reality, and artificial intelligence algorithms, implemented into a Raspberry Pi board with Python programming language. METHODS: Two training tasks were evaluated by the laparoscopic system: transferring and pattern cutting. Computer vision libraries were used to obtain the number of transferred points and simulated pattern cutting trace by means of tracking of the laparoscopic instrument. An artificial neural network (ANN) was trained to learn from experts and nonexperts' behavior for pattern cutting task, whereas the assessment of transferring task was performed using a preestablished threshold. Four expert surgeons in laparoscopic surgery, from hospital "Raymundo Abarca Alarcón," constituted the experienced class for the ANN. Sixteen trainees (10 medical students and 6 residents) without laparoscopic surgical skills and limited experience in minimal invasive techniques from School of Medicine at Universidad Autónoma de Guerrero constituted the nonexperienced class. Data from participants performing 5 daily repetitions for each task during 5 days were used to build the ANN. RESULTS: The participants tend to improve their learning curve and dexterity with this laparoscopic training system. The classifier shows mean accuracy and receiver operating characteristic curve of 90.98% and 0.93, respectively. Moreover, the ANN was able to evaluate the psychomotor skills of users into 2 classes: experienced or nonexperienced. CONCLUSION: We constructed and evaluated an affordable laparoscopic trainer system using computer vision, augmented reality, and an artificial intelligence algorithm. The proposed trainer has the potential to increase the self-confidence of trainees and to be applied to programs with limited resources.

Construct validity of a video-tracking system based on orthogonal cameras approach for objective assessment of laparoscopic skills.

PURPOSE: This study was aimed to establish the construct validity of a video-tracking system based on orthogonal cameras approach for assessment of laparoscopic psychomotor skills in training environments. METHODS: The camera-tracking system consists of two webcams placed in orthogonal configuration at a distance of 13.5 cm. The orthogonal cameras employ a color segmentation algorithm to register the 3D motions of the laparoscopic instruments using colored tapes placed on the distal end. For construct validity, 31 participants (4 experts and 27 residents) performed three training tasks in a laparoscopic box trainer with the built-in orthogonal cameras system. Eleven motion-related parameters were used to evaluate their performance. Statistical analysis was performed, and results between two groups were compared using a Mann-Whitney U-test. RESULTS: Construct validity results showed statistical differences in almost all motion-related parameters for assessment of laparoscopic technical skills. Results demonstrated that the orthogonal video-based tracking system was able to differentiate laparoscopic experience between experts and trainees surgeons. CONCLUSION: The orthogonal cameras system was successfully validated in a laparoscopic box trainer. This video-based tracking system was able to distinguish performance between experts and trainees surgeons, showing its potential as a reliable tool to assess laparoscopic psychomotor skills. The orthogonal cameras allow incorporating the advantages of this video motion-tracking technology with the benefits of the traditional laparoscopic box trainers, creating realistic haptic feedback and allowing the evaluation of psychomotor skills of the surgeons.

Construction and validation of a low-cost surgical trainer based on iPhone technology for training laparoscopic skills.

In this article, we describe the construction and validation of a laparoscopic trainer using an iPhone 5 and a plastic document holder case. The abdominal cavity was simulated with a clear plastic document holder case. On 1 side of the case, 2 holes for entry of laparoscopic instruments were drilled. We added a window to place the camera of the iPhone, which works as our camera of the trainer. Twenty residents carried out 4 tasks using the iPhone Trainer and a physical laparoscopic trainer. The time of all tasks were analyzed with a simple paired t test. The construction of the trainer took 1 hour, with a cost of