Learning curve

Background Robotic telemanipulation systems provide solutions to the problems of less dexterity and visual constraints of minimally invasive surgery (MIS). However, their influence over surgeons’ dexterity and learning curve needs to be assessed. We present motion analysis as an objective method to measure performance and learning progress. Methods Thirteen surgeons completed five synthetic small bowel anastomoses using the da Vinci system. Objective Structured Assessment of Technical Skills (OSATS) allowed qualitative analysis. Quantitative analysis used API software of the system to retrieve real-time robotic signal data of time, path length, and number of movements. Wilcoxon signed ranks test was used for statistical analysis. A p value <0.05 was considered significant. Results OSATS global scores were 18.6 points for the first attempt and 26 for the fifth attempt (p < 0.02, Cronbach’s alpha = 0.894). Paired data of motion analysis for attempts 1 vs 5 showed significant change: time taken 3507 sec and 2287 sec (p < 0.008), total number of movements 2411 and 1387 (p = 0.01), total path length 21,630 cm and 13,941 cm (p = 0.01). Conclusions A rapid learning curve to a competent level using the da Vinci system is possible aided by the system’s intuitive motion. Motion analysis is a useful tool to measure performance in the da Vinci system compared to OSATS and time alone.

The development of new instrumentation and techniques has led to the rapid advancement of less invasive surgical approaches in total knee arthroplasty (TKA). Compared to the standard approach, minimally invasive surgery (MIS) in TKA was shown to reduce postoperative pain, blood loss, and hospitalization time, and to improve functional recovery. Growing experience with MIS-TKA has defined the proper indications for this technique. With a limited exposure, the skin, capsular tissues, and bone surfaces receive higher stresses because of the retraction required. Several complications relating to the MIS learning curve are now being reported. The reliability of a TKA procedure performed through a mini-incision, and its success, seems to depend on patient selection, surgeon experience, and surgical environment.

ObjectiveTo determine the number of ultrasound examinations necessary for training sonographers to examine accurately the fetal nasal bone at 11–14 weeks' gestation.To determine the number of ultrasound examinations necessary for training sonographers to examine accurately the fetal nasal bone at 11–14 weeks' gestation.MethodsFifteen sonographers with experience in measuring nuchal translucency were asked to examine the nasal bone during the routine 11–14-week scan. The supervising doctor recorded if the sonographer succeeded in obtaining the correct image. Each sonographer performed a total of 140 examinations, and the data were analyzed in seven groups of 20 examinations. In a second study, two sonographers with extensive experience in examining the nasal bone examined independently 100 consecutive patients at a median fetal crown–rump length of 65 (45–84) mm and median gestational age of 12 (11–14) weeks and recorded whether the nasal bone was absent or present.Fifteen sonographers with experience in measuring nuchal translucency were asked to examine the nasal bone during the routine 11–14-week scan. The supervising doctor recorded if the sonographer succeeded in obtaining the correct image. Each sonographer performed a total of 140 examinations, and the data were analyzed in seven groups of 20 examinations. In a second study, two sonographers with extensive experience in examining the nasal bone examined independently 100 consecutive patients at a median fetal crown–rump length of 65 (45–84) mm and median gestational age of 12 (11–14) weeks and recorded whether the nasal bone was absent or present.ResultsIn the first group of 20 examinations, there was failure to obtain the correct image of the fetal profile in 1–5 (median, 4) cases. In the subsequent three groups, there was failure to obtain the correct image in 0–3 (median, 1) cases. In the fifth and sixth groups failure occurred in 0–2 (median, 0) cases and in the seventh group all sonographers obtained successful images of the fetal profile in all cases. One sonographer obtained successful images of all cases after the first 40 scans, four after the first 60 scans, six after the first 80 and two each after the first 100 and 120 scans. In the second study, there was agreement between the two sonographers that the nasal bone was absent in two and present in 98 of the 100 consecutive patients examined.In the first group of 20 examinations, there was failure to obtain the correct image of the fetal profile in 1–5 (median, 4) cases. In the subsequent three groups, there was failure to obtain the correct image in 0–3 (median, 1) cases. In the fifth and sixth groups failure occurred in 0–2 (median, 0) cases and in the seventh group all sonographers obtained successful images of the fetal profile in all cases. One sonographer obtained successful images of all cases after the first 40 scans, four after the first 60 scans, six after the first 80 and two each after the first 100 and 120 scans. In the second study, there was agreement between the two sonographers that the nasal bone was absent in two and present in 98 of the 100 consecutive patients examined.ConclusionThe minimum number of scans required for an experienced sonographer to become competent in examining the fetal nasal bone is on average 80, with a range of 40–120. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.The minimum number of scans required for an experienced sonographer to become competent in examining the fetal nasal bone is on average 80, with a range of 40–120. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.

This paper presents our solution to solve the challenge presented at the 3DUI 2012 Contest. The challenge consisted of assisted collaborative navigation in a 3D environment. One user (called power user) has a global view of the 3D environment; alternatively, the other user (called explorer) has a first person view of the environment. The power user uses co-located gestures to manipulate and explore the VR Environment in a power wall like display. These gestures allow the power user to rotate, translate, zoom and place cues for the explorer within the environment, effectively aiding him. The explorer navigates the scene by means of a point and go metaphor: he points to where he wants to go using an optically tracked Wiimote controller; a virtual line connecting the Wiimote in his hand and the target surface is rendered in the VR Environment. We have chosen to use point light sources as cues to the explorer. These point lights show the explorer which direction he should follow to complete the scavenger hunt through the VR Environment. We performed an informal user study showed that users enjoyed completing the given task, despite the initial learning curve for the power user role.

Background Robotic telemanipulation systems provide solutions to the problems of less dexterity and visual constraints of minimally invasive surgery (MIS). However, their influence over surgeons’ dexterity and learning curve needs to be assessed. We present motion analysis as an objective method to measure performance and learning progress. Methods Thirteen surgeons completed five synthetic small bowel anastomoses using the da Vinci system. Objective Structured Assessment of Technical Skills (OSATS) allowed qualitative analysis. Quantitative analysis used API software of the system to retrieve real-time robotic signal data of time, path length, and number of movements. Wilcoxon signed ranks test was used for statistical analysis. A p value <0.05 was considered significant. Results OSATS global scores were 18.6 points for the first attempt and 26 for the fifth attempt (p < 0.02, Cronbach’s alpha = 0.894). Paired data of motion analysis for attempts 1 vs 5 showed significant change: time taken 3507 sec and 2287 sec (p < 0.008), total number of movements 2411 and 1387 (p = 0.01), total path length 21,630 cm and 13,941 cm (p = 0.01). Conclusions A rapid learning curve to a competent level using the da Vinci system is possible aided by the system’s intuitive motion. Motion analysis is a useful tool to measure performance in the da Vinci system compared to OSATS and time alone.

Background: After more than 8 years of working in the field, we thought it would be interesting to evaluate our experience in the laparoscopic repair of abdominal wall hernias, focusing attention on the lessons learned with time. Methods: From January 1994 to November of 2000, a total of 270 patients with abdominal wall hernias were treated in our center using the laparoscopic approach. The data collected and analyzed were preoperative evaluation, operative findings, early and long-term complications, and recurrences. Results: The mean follow-up time was 44 months, mean surgical time was 85 min, and mean hospital stay was 1.5 days. The average number of abdominal wall defects was 4.8 per patient. There were 9 (3.3%) small bowel perforations. Conversion to open surgery was required in 1 case (0.3%). Minor early postoperative complications occurred in 38 patients (14.07%). Twenty patients (7.4%) developed persistent postoperative abdominal pain. There was 1 case (0.3%) of small bowel incarceration through the mesh border and another case (0.3%) of small bowel leakage due to ischemia and subsequent peritonitis. The relapse rate was 4.4% (12 cases). Conclusion: The laparoscopic approach is a valuable option in the management of abdominal wall hernias, but it requires experience in laparoscopic surgery and there is a specific learning curve for the technique.

Introduction: Many health technologies exhibit some form of learning effect, and this represents a barrier to rigorous assessment. It has been shown that the statistical methods used are relatively crude. Methods to describe learning curves in fields outside medicine, for example, psychology and engineering, may be better.

Background Laparoscopic assisted colectomy (LAC) is a difficult operation with long learning curves and conversion rates inversely proportional to the surgeon’s experience. Methods to help train surgeons outside of residency or fellowship programs have been poorly analyzed. This study was undertaken to assess the impact of an experienced laparoscopic surgeon preceptor on the outcome of LAC in a single institution Methods In September 2004, a fellowship-trained laparoscopic surgeon joined our department of surgery. This surgeon served as a LAC preceptor for six inexperienced staff surgeons and four surgical oncology fellows. Clinical and pathologic data from all attempted LAC for the 22 months preceding the arrival of the trained laparoscopic surgeon were compared with those for the 18 months following the recruitment. Results Before the addition of the expert surgeon, 28 LAC were performed in our institution, compared with 63 during the preceptor program. These represented 59% and 95% of eligible operations for each time period, respectively (P = 0.005). Overall conversion rates before and after the preceptor’s arrival decreased from 44% to 14%, respectively (P < 0.05). The chances of conversion were strongly affected by the presence or absence of the preceptor in the operating room (7% vs. 30%, respectively, P = 0.003). Overall complication rates, hospital stay, blood loss, operative time and number of lymph nodes retrieved were not affected by the presence of the preceptor. Operations completed laparoscopically resulted in significantly lower blood loss and length of stay compared with converted ones. Conclusions A shared departmental preceptor can positively affect the institutional outcome of laparoscopic colectomy. This model may help improve training and patient care in inexperienced centers.

Background Little evidence exists to guide educators in the best way to implement simulation within surgical skills curricula. This study investigated whether practicing a basic Fundamentals of Laparoscopic Surgery (FLS) simulator task [peg transfer (PT)] facilitates learning a more complex skill [intracorporeal suturing (ICS)] and compared the effect of PT training to mastery with training to the passing level on PT retention and on learning ICS. Methods For this study, 98 surgically naïve subjects were randomized to one of three PT training groups: control, standard training, and overtraining. All the participants then trained in ICS. The learning curves for ICS were analyzed by estimating the learning plateau and rate using nonlinear regression. Skill retention was assessed by retesting participants 1 month after training. The groups were compared using analysis of variance (ANOVA). Effectiveness of skill transfer was calculated using the transfer effectiveness ratio (TER). Data are presented as mean ± standard deviation (p < 0.05). Results The study was completed by 77 participants (28 control, 26 standard, and 23 overtrained subjects). The ICS learning plateau rose with increasing PT training (452 ± 10 vs. 459 ± 10 vs. 467 ± 10; p < 0.01). Increased PT training was associated with a trend toward higher initial ICS scores (128 ± 107 vs. 127 ± 110 vs. 183 ± 106; p = 0.13) and faster learning rates (15 ± 4 vs. 14 ± 4 vs. 13 ± 4 trials; p = 0.10). At retention, there were no differences in PT scores (p = 0.5). The PT training took 20 ± 10 min for standard training and 39 ± 20 min for overtraining (p < 0.01). Overtrained participants saved 11 ± 5 min in ICS training compared with the control subjects (p = 0.04). However, TER was 0.165 for the overtraining group and 0.160 for the standard training group, suggesting that PT overtraining took longer than the time saved on ICS training. Conclusion For surgically naïve subjects, part-task training with PT alone was associated with slight improvements in the learning curve for ICS. However, overtraining with PT did not improve skill retention, and peg training alone was not an efficient strategy for learning ICS.