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Minimally invasive surgery (MIS) requires a high degree of eye–hand coordination from the surgeon. To facilitate the learning process, objective assessment systems based on analysis of the instruments’ motion are being developed. To investigate the influence of performance on motion characteristics, we examined goal-oriented movements in a box trainer. In general, goal-oriented movements consist of a retracting and a seeking phase, and are, however, not performed via the shortest path length. Therefore, we hypothesized that the shortest path is not an optimal concept in MIS. Participants were divided into three groups (experts, residents, and novices). Each participant performed a number of one-hand positioning tasks in a box trainer. Movements of the instrument were recorded with the TrEndo tracking system. The movement from point A to B was divided into two phases: A-M (retracting) and M-B (seeking). Normalized path lengths (given in %) of the two phases were compared. Thirty eight participants contributed. For the retracting phase, we found no significant difference between experts [median (range) %: 152 (129–178)], residents [164 (126–250)], and novices [168 (136–268)]. In the seeking phase, we find a significant difference (<0.001) between experts [180 (172–247)], residents [201 (163–287)], and novices [290 (244–469)]. Moreover, within each group, a significant difference between retracting and seeking phases was observed. Goal-oriented movements in MIS can be split into two phases: retracting and seeking. Novices are less effective than experts and residents in the seeking phase. Therefore, the seeking phase is characteristic of performance differences. Furthermore, the retracting phase is essential, because it improves safety by avoiding intermediate tissue contact. Therefore, the shortest path length, as presently used during the assessment of basic MIS skills, may be not a proper concept for analyzing optimal movements and, therefore, needs to be revised. [ABSTRACT FROM AUTHOR]

Background: To improve endoscopic surgical skills, an increasing number of surgical residents practice on box or virtual-reality (VR) trainers. Current training is mainly focused on hand-eye coordination. Training methods that focus on applying the right amount of force are not yet available. Methods: The aim of this project is to develop a system to measure forces and torques during laparoscopic training tasks as well as the development of force parameters that assess tissue manipulation tasks. The force and torque measurement range of the developed force platform are 0-4 N and 1 Nm (torque), respectively. To show the potential of the developed force platform, a pilot study was conducted in which five surgeons experienced in intracorporeal suturing and five novices performed a suture task in a box trainer. Results: During the pilot study, the maximum and mean absolute nonzero force that the novice used were 4.7 N (SD 1.3 N) and 2.1 N (SD 0.6 N), respectively. With a maximum force of 2.6 N (SD 0.4 N) and mean nonzero force of 0.9 N (SD 0.3 N), the force exerted by the experts was significantly lower. Conclusions: The designed platform is easy to build, affordable, and accurate and sensitive enough to reflect the most important differences in, e.g., maximal force, mean force, and standard deviation. Furthermore, the compact design makes it possible to use the force platform in most box trainers. [ABSTRACT FROM AUTHOR]

In minimally invasive surgery (MIS), a surgeon needs to acquire a certain level of basic psychomotor MIS skills to perform surgery safely. Evaluation of those skills is a major impediment. Although various assessment methods have been introduced, none of them came as a superior. Three aspects of assessing psychomotor MIS skills are discussed here: (i) advantages and disadvantages of currently available assessment methods, (ii) methods to objectively classify residents according to their level of psychomotor skills, and (iii) factors that influence psychomotor MIS skills. Motion analysis has a potential to be the means to deal with assessment of psychomotor skills. Together with classification methods (e.g. linear discriminant analysis), motion analysis provides an aid in deciding whether a resident is ready to move to the next level of training. Presence of factors that influence psychomotor MIS skills results in a high need for standardisation of valid tasks and setups used for the assessment of MIS skills. [ABSTRACT FROM AUTHOR]

Purpose: To assess the safety and effectiveness of LESS compared to conventional hysterectomy.Methods: The systematic review and meta-analysis was performed according to the MOOSE guideline, and quality of evidence was assessed using GRADE. Different databases were searched up to 4th of August 2016. Randomized controlled trials and cohort studies comparing LESS to the conventional laparoscopic hysterectomy were considered for inclusion.Results: Of the 668 unique articles, 23 were found relevant. We investigated safety by analyzing the complication rate and found no significant differences between both groups [OR 0.94 (0.61, 1.44), I 2 = 19%]. We assessed effectiveness by analyzing conversion risk, postoperative pain, and patient satisfaction. For conversion rates to laparotomy, no differences were identified [OR 1.60 (0.40, 6.38), I 2 = 45%]. In 3.5% of the cases in the LESS group, an additional port was needed during LESS. For postoperative pain scores and patient satisfaction, some of the included studies reported favorable results for LESS, but the clinical relevance was non-significant. Concerning secondary outcomes, only a difference in operative time was found in favor of the conventional group [MD 11.3 min (5.45-17.17), I 2 = 89%]. The quality of evidence for our primary outcomes was low or very low due to the study designs and lack of power for the specified outcomes. Therefore, caution is urged when interpreting the results.Conclusion: The single-port technique for benign hysterectomy is feasible, safe, and equally effective compared to the conventional technique. No clinically relevant advantages were identified, and as no data on cost effectiveness are available, there are currently not enough valid arguments to broadly implement LESS for hysterectomy. [ABSTRACT FROM AUTHOR]

Background: Currently, task time and errors are often used as performance parameters in laparoscopic training. Training with the focus on task time improvement alone results in fast, but possibly less controlled, instrument movements and therefore suboptimal tissue handling skills. Methods: Twenty-five medical students were randomly assigned in two groups. Both groups performed a tissue manipulation task six times. During this training session, the time feedback group ( n = 13) received real-time visual feedback of the task time. The force feedback group ( n = 12) received real-time visual feedback of the tissue manipulation force. After the training sessions, participants in both groups performed an entirely different task without visual feedback. Task time, force, and motion parameters of this posttest were used to compare the technical skills of the medical students. Results: The training data of the group that received force feedback showed a learning curve for the mean and max absolute force, max force area, force volume, task time, and path length of both instruments. The data from the group that received time feedback showed a learning curve for the max force, task time, and path length of both instruments. In the posttest, the parameters of mean absolute force ( p = 0.039), max force ( p = 0.041), and force volume ( p = 0.009) showed a significant difference in favor of the group that received force feedback. Conclusions: The learning curves and the posttest indicate that training with visual force feedback improves tissue handling skills with no negative effect on the task time and instrument motions. Conventional laparoscopic training with visual time feedback improves instrument motion and task time, but it does not improve tissue manipulation skills. [ABSTRACT FROM AUTHOR]

Background: To improve endoscopic surgical skills, an increasing number of surgical residents practice on box or virtual reality (VR) trainers. Current training is focused mainly on hand-eye coordination. Training methods that focus on applying the right amount of force are not yet available. Methods: The aim of this project is to develop a low-cost training system that measures the interaction force between tissue and instruments and displays a visual representation of the applied forces inside the camera image. This visual representation continuously informs the subject about the magnitude and the direction of applied forces. To show the potential of the developed training system, a pilot study was conducted in which six novices performed a needle-driving task in a box trainer with visual feedback of the force, and six novices performed the same task without visual feedback of the force. All subjects performed the training task five times and were subsequently tested in a post-test without visual feedback. Results: The subjects who received visual feedback during training exerted on average 1.3 N (STD 0.6 N) to drive the needle through the tissue during the post-test. This value was considerably higher for the group that received no feedback (2.6 N, STD 0.9 N). The maximum interaction force during the post-test was noticeably lower for the feedback group (4.1 N, STD 1.1 N) compared with that of the control group (8.0 N, STD 3.3 N). Conclusions: The force-sensing training system provides us with the unique possibility to objectively assess tissue-handling skills in a laboratory setting. The real-time visualization of applied forces during training may facilitate acquisition of tissue-handling skills in complex laparoscopic tasks and could stimulate proficiency gain curves of trainees. However, larger randomized trials that also include other tasks are necessary to determine whether training with visual feedback about forces reduces the interaction force during laparoscopic surgery. [ABSTRACT FROM AUTHOR]

Not much is known about the exact role of force feedback in laparoscopy. This study aimed to determine whether force feedback influences movements of instruments during training in laparoscopic tasks and whether force feedback is required for training in basic laparoscopic force application tasks. A group of 19 gynecologic residents, randomly divided into two groups, performed three laparoscopic tasks in both the box trainer and the virtual reality (VR) trainer. The box-VR group began with the box trainer, whereas the VR-box group began with the VR trainer. The three selected tasks included different levels of force application. The box trainer provides natural force feedback, whereas the VR trainer does not provide force feedback. The performance of the two groups was compared with regard to time, path length, and depth perception. For the tasks in which force plays hardly a role, no differences between box-VR group and the VR-box group were found. During a task in which force application (pulling and pushing forces) plays a role, the box-VR group outperformed VR-box group in the box trainer. Moreover, training with the box trainer had a positive effect on subsequent performance of the task with the VR trainer. This was not found the other way around. No differences were found between box-VR and the VR-box group in tasks not requiring force application. Force feedback influences basic laparoscopic skills during tasks in which pulling and pushing forces are applied. For these tasks, the switch from the trainer without force feedback to the one with natural force feedback has a detrimental effect on performance. Therefore, training for tasks in which forces play an important role (e.g., stretching, grasping) should be done using systems with natural force feedback, whereas eye–hand coordination can be trained without force feedback. [ABSTRACT FROM AUTHOR]

Background: To evaluate the effect of a mentor traineeship in laparoscopic surgery in a teaching hospital. Method: This observational study was performed between January 1997 and December 2004 at Bronovo Hospital, The Hague, The Netherlands. Since January 2001, an advanced endoscopic gynecologist has mentored a trainee in laparoscopic surgery. Data on the trainee’s procedures preceding (1997–2000) and during the mentor traineeship (2001–2004) were compared. The number and type of procedures performed, complications and conversions were derived from a prospectively kept database supplemented by a retrospective chart review. Operating times for total laparoscopic hysterectomy (TLH) were registered to establish the trainee’s learning curve. Results: Since the presence of a mentor, the trainee has performed significantly more advanced laparoscopic procedures. Despite the significant increase in advanced cases, the trainee’s laparoscopic conversion rate to laparotomy remained stable between period 1 and period 2 (7.5 and 4.5%, respectively, p = 0.35, 95% CI –0.033 to 0.092); moreover, for level-3 procedures the conversion rate decreased (p < 0.001, 95% CI 0.30–0.71). Despite the increase in advanced cases, the total complication rate remained stable (3.2–4.5%, p = 0.62, 95% CI –0.07 to 0.04) including the number of level-3 complications (p = 0.63, 95% CI –0.4 to 0.3). A decreasing trend in operating time for TLH was found; however, this was not significant (Spearman correlation coefficient –0.421, p = 0.81). Conclusions: Mentor traineeship in gynecology enhanced the advanced laparoscopic caseload. With the increase in advanced procedures, no increase in conversion rate, complication rate or operating times for TLH was found. Due to the mentorship, patients were not exposed to increased complications and conversions, or to the disadvantages of a prolonged operating time. Predominantly, mentor traineeship facilitated the implementation of laparoscopic surgery into an established gynecological practice in a teaching hospital. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]