Validation of LapSim®

Surgical Skills Assessment of Applicants to General Surgery Residency

Panait L, Larios JM, Brenes RA, Fancher TT, Ajemian MS, Dudrick SJ, Sanchez JA,

J Surg Res 2011

BACKGROUND: Manual skill proficiency is not currently employed in selecting residents for general surgery training programs. The study objective was to assess whether the technical skill levels of applicants to a general surgery residency program are higher than those of internal medicine residents.

MATERIAL AND METHODS: Forty-two applicants to a community general surgery program underwent manual skill testing on interview day. Four laparoscopic tasks on a virtual reality (VR) simulator (LapSim, Goteborg, Sweden) were tested. Performance scores were computer-generated. Participants’ previous experience with other manual dexterity activities was assessed via a questionnaire. Applicants’ selfperception of their surgical skills was correlated with their skill dexterity scores on the simulator. Candidates’ simulator scores were also compared with those of a group of internal medicine interns (n=9) and a group of mid-level surgical residents, PGY 2-3 (n=7).

RESULTS: Simulator scores of the applicants were significantly lower than those of mid-level surgical residents in all VR tasks (P<0.05). The internal medicine interns scored higher that the surgery candidates in three of four simulator tasks. Participation in other manual dexterity activities was not associated with increased dexterity scores.

CONCLUSION: This study suggests that surgical dexterity levels do not correlate with the self-assessed skill levels or with previous experience with other manual dexterity activities. Moreover, there appears to be no self-selection of applicants for surgery residency based on actual surgical skills. Selection criteria for surgical training, which incorporate technical proficiency skills, may potentially better discriminate those applicants with an aptitude for a surgical specialty.

Warm-up in a Virtual Reality Environment Improves Performance in the Operating Room.

Dan Calatayud, MD,* Sonal Arora, MBBS,† Rajesh Aggarwal, PhD,† Irina Kruglikova, MD,‡

Svend Schulze, DSc,* Peter Funch-Jensen, DSc,‡ and Teodor Grantcharov, PhD§

(Ann Surg 2010;251: 1181–1185)

OBJECTIVE: To assess the impact of warm-up on laparoscopic performance in the operating room (OR). Background: Implementation of simulation-based training into clinical practice remains limited despite evidence to show that the improvement in skills is transferred to the OR. The aim of this study was to evaluate the impact of a short virtual reality warm-up training program on laparoscopic performance in the OP. Methods: Sixteen Laparoscopic Cholecystectomies were performed by 8 surgeons in the OR. Participants were randomized to a group which received a preprocedure warm-up using a virtual reality simulator and no warm-up group. After the initial laparoscopic cholecystectomy all surgeons served as their own controls by performing another procedure with or without preoperative warm-up. All OR procedures were videotaped and assessed by 2 independent observers using the generic OSATS global rating scale (from 7 to 35).

RESULTS: There was significantly better surgical performance on the laparoscopic Cholecystectomy following preoperative warm-up, median 28.5 (range _ 18.5–32.0) versus median 19.25 (range _ 15–31.5), P _ 0.042. The results demonstrated excellent reliability of the assessment tool used (Cronbach’s _ _ 0.92).

CONCLUSION: This study showed a significant beneficial impact of warm-up on laparoscopic performance in the OP. The suggested program is short, easy to perform, and therefore realistic to implement in the daily life in a busy surgical department. This will potentially improve the procedural outcome and contribute to improved patient safety and better utilization of OR resources.

Telementoring versus on-site mentoring in virtual reality-based surgical training.

Panait L, Rafiq A, Tomulescu V, Boanca C, Popescu I, Carbonell A, Merrell RC.

Surg Endosc. 2006 Jan;20(1):113-8. Epub 2005 Oct 24.

BACKGROUND: Telementoring can be an adjunct to surgical training using virtual reality surgical simulation. Telementoring is hypothesized to be as effective as a local mentor for surgical skills training.

METHODS: In this study, 20 Romanian medical students trained using a virtual reality surgical simulator (LapSim) with a telementor or local mentor. All the students watched an instructional module at the beginning of the exercise. The telementor, in the United States, interacted by videoconferencing. Before and after training sessions, tool path length and time for task completion were measured.

RESULTS: Instructional media and training with mentoring resulted in similar levels of performance between locally mentored and telementored groups. Right- and left-hand path length and time decreased significantly within each group from the initial to the final evaluation (p < 0.05) for most tasks (grasping, cutting, suturing). No significant difference was achieved for clip-applying. CONCLUSIONS: Integration of instructional media with telementoring can be as effective for the development of surgical skills as local mentoring.

Face and construct validity of virtual reality simulation of laparoscopic gynecologic surgery.

Schreuder HW, van Dongen KW, Roeleveld SJ, Schijven MP, Broeders IA.

Am J Obstet Gynecol. 2009 Mar 12. (Epub ahead of print,)

OBJECTIVE: The objective of the study was to validate virtual reality simulation in assessing laparoscopic skills in gynecology by establishing the extent of realism of the simulation to the actual task (face validity) and the degree to which the results of the test one uses reflects the subject tested (construct validity).

STUDY DESIGN: Subjects (n = 56) were divided into 3 groups: novices (n = 15), intermediates (n = 20), and experts (n = 21). Participants completed 3 repetitions of a training program consisting of 4 basic skills and 3 gynecologic procedural simulations. The performance was compared between groups using a post hoc Student t test with the Bonferroni technique. Face validity was determined by using a questionnaire of 27 statements.

RESULTS: Resulting from the questionnaire, the opinion about the realism and training capacities of the tasks was favorable among all groups. The degree of prior laparoscopic experience was reflected in the outcome performance parameters of the tasks. Experts achieved significant better scores on specific parameters.

CONCLUSION: The results of this study indicate acceptance and thus face validity of the system among both reference (novice, intermediate) and expert group. There is a significant difference between subjects with different laparoscopic experience and thereby construct validity for the laparoscopic simulator could be established.

The impact of self-belief on laparoscopic performance of novices and experienced surgeons.

Maschuw K, Osei-Agyemang T, Weyers P, Danila R, Bin Dayne K, Rothmund M, Hassan I.

World J Surg. 2008 Sep;32(9):1911-6.

BACKGROUND: In many professions, nontechnical aspects such as motivation or coping with stress are known to influence performance, success, and outcome. These qualities are assessed and trained in novices for quality and safety reasons. This study explored the impact of self-belief of surgeons on laparoscopic performance using a virtual reality simulator (LapSim).

METHODS: Eighteen inexperienced surgical residents (with less than ten laparoscopic procedures performed) and 22 advanced residents (with more than 50 laparoscopic procedures performed) filled out a ten-item questionnaire used for the assessment of the individual sense of general self-efficacy (GSE). Afterward the participants were asked to perform three defined tasks on the LapSim, each at two different levels of difficulty. The tasks consisted of coordination, dissection, and application of clips. To assess laparoscopic performance, the total time to complete the tasks, economy of motion, and damage parameters were analyzed and correlated with the GSE score by means of Bravis-Pearson correlation analysis.

RESULTS: In novices, high GSE scores correlated with more errors and poor economy of motion, while in advanced residents, laparoscopic performance was independent of the level of assessed self-efficacy. CONCLUSION: In a small sample, high self-belief does not predict success. In novices it negatively correlates with laparoscopic skills, while in advanced residents it is independent of laparoscopic performance. Thus, training aspects seem to be of greater importance for laparoscopic skills. Nevertheless, nontechnical aspects like self-belief, motivation, stress-coping strategies, judgment, decision-making, and leadership should be included in the surgical curriculum.

Does box model training improve surgical dexterity and economy of movement during virtual reality laparoscopy? A randomised trial.

Clevin L, Grantcharov TP

Acta Obstet Gynecol Scand. 2008;87(1):99-103.

Comment in: Acta Obstet Gynecol Scand. 2008;87(5):579-81.

OBJECTIVE: Laparoscopic box model trainers have been used in training curricula for a long time, however data on their impact on skills acquisition is still limited. Our aim was to validate a low cost box model trainer as a tool for the training of skills relevant to laparoscopic surgery.

DESIGN: Randomised, controlled trial (Canadian Task Force Classification I).

SETTING: University Hospital.

MEASUREMENTS AND MAIN RESULTS: Sixteen gynaecologic residents with limited laparoscopic experience were randomised to a group that received a structured box model training curriculum, and a control group. Performance before and after the training was assessed in a virtual reality laparoscopic trainer (LapSim and was based on objective parameters, registered by the computer system (time, error, and economy of motion scores). Group A showed significantly greater improvement in all performance parameters compared with the control group: economy of movement (p=0.001), time (p=0.001) and tissue damage (p=0.036), confirming the positive impact of box-trainer curriculum on laparoscopic skills acquisition. CONCLUSIONS: Structured laparoscopic skill training on a low cost box model trainer improves performance as assessed using the VR system. Trainees who used the box model trainer showed significant improvement compared to the control group. Box model trainers are valid tools for laparoscopic skills training and should be implemented in the comprehensive training curricula in gynaecology.

Is virtual reality simulation an effective training method in surgery?

Grantcharov TP.

Nat Clin Pract Gastroenterol Hepatol. 2008 May;5(5):232-3. Epub 2008 Apr 1.

No abstract available

Training opportunities and the role of virtual reality simulation in acquisition of basic laparoscopic skills.

Aggarwal R, Balasundaram I, Darzi A.

J Surg Res. 2008 Mar;145(1):80-6. Epub 2007 Oct 22.

BACKGROUND: Within the past decade, there has been increasing interest in simulation-based devices for training and assessment of technical skills, especially for minimally invasive techniques such as laparoscopy. The aim of this study was to investigate the perceptions of senior and junior surgeons to virtual reality simulation within the context of current training opportunities for basic laparoscopic procedures.

METHODS: A postal questionnaire was sent to 245 consultants and their corresponding specialist registrar (SpR), detailing laparoscopic surgical practice and their knowledge and use of virtual reality (VR) surgical simulators.

RESULTS: One hundred ninety-one (78%) consultants and 103(42%) SpRs returned questionnaires; 16%(10/61) of junior SpRs (year 1-4) had performed more than 50 laparoscopic cholecystectomies to date compared with 76% (32/42) of senior SpRs (year 5-6) (P < 0.001); 90% (55/61) of junior SpRs and 67% (28/42) of senior SpRs were keen to augment their training with VR (P = 0.007); 81% (238/294) of all surgeons agreed that VR has a useful role in the laparoscopic surgical training curriculum.

CONCLUSIONS: There is a lack of experience in index laparoscopic cases of junior SpRs, and laparoscopic VR simulation is recognized as a useful mode of practice to acquire technical skills. This should encourage surgical program directors to drive the integration of simulation-based training into the surgical curriculum.

Correlating virtual reality and box trainer tasks in the assessment of laparoscopic surgical skills.

Newmark D, Dandolu V, Milner R, Grewal H, Harbison S, Hernandez E.

Am J Obstet Gynecol. 2007 Nov; 197(5) 546.e1-4.

OBJECTIVE: The purpose of this study was to examine the correlation in the assessment of laparoscopic surgical skills in medical students with the use of a virtual reality laparoscopic trainer and a low-fidelity video box trainer with comparative tasks.

STUDY DESIGN: Third-year medical students were asked to perform 3 basic skills set modules on LapSim (Surgical Science, Gothenburg, Sweden): coordination, grasping and lifting, and handling the intestines. Each task was set at the easiest level, and each student was allowed a maximum of 10 attempts to complete each task. Similar-appearing tasks were chosen for comparison with the use of a standard video box trainer: pegboard, cup drop and rope pass, respectively. Laparoscopic skills were evaluated with the use of both trainers during 1 session. Pearson’s correlation coefficients were used to compare paired data on each student using statistical software.

RESULTS: Forty-seven of 65 medical students were assigned to clinical clerkships on-campus at Temple University School of Medicine participated in the study. All 47 students participated in the video box trainer tasks; 34 students completed both the video box trainer and LapSim skills set. Observations that were obtained on the LapSim virtual reality system and video box trainer simulator demonstrated several correlations. The time to completion for the LapSim coordination task and the pegboard task were correlated (r = 0.507; P = .006), as were the grasping and lifting task completion time on LapSim and the comparative box trainer cup drop task completion time (r = 0.404; P = .022). When accounting for errors, the LapSim coordination task tissue damage score was correlated with the sum of all box trainer errors (r = 0.353; P = .040); the average grasping and lifting tissue damage was correlated with the total number of errors during all box trainer tasks (r = 0.374; P = .035). CONCLUSION: Overall, in evaluating laparoscopic skills, the LapSim and video box trainer were correlated positively with one another. The scoring of laparoscopic skills by both systems appears to be equivalent for the measurement of time to task completion and number of errors.

Construct validity of the LapSim: can the LapSim virtual reality simulator distinguish between novices and experts?

van Dongen KW, Tournoij E, van der Zee DC, Schijven MP, Broeders IA.

Surg Endosc. 2007 Aug;21(8):1413-7. Epub 2007 Feb 9.

BACKGROUND: Virtual reality simulators may be invaluable in training and assessing future endoscopic surgeons. The purpose of this study was to investigate if the results of a training session reflect the actual skill of the trainee who is being assessed and thereby establish construct validity for the LapSim virtual reality simulator (Surgical Science Ltd., Gothenburg, Sweden).

METHODS: Forty-eight subjects were assigned to one of three groups: 16 novices (0 endoscopic procedures), 16 surgical residents in training (>10 but <100 endoscopic procedures), and 16 experienced endoscopic surgeons (>100 endoscopic procedures). Performance was measured by a relative scoring system that combines single parameters measured by the computer. RESULTS: The higher the level of endoscopic experience of a participant, the higher the score. Experienced surgeons and surgical residents in training showed statistically significant higher scores than novices for both overall score and efficiency, speed, and precision parameters.

CONCLUSIONS: Our results show that performance of the various tasks on the simulator corresponds to the respective level of endoscopic experience in our research population. This study demonstrates construct validity for the LapSim virtual reality simulator. It thus measures relevant skills and can be integrated in an endoscopic training and assessment program.

Virtual reality laparoscopic skill assessment in microgravity.

Panait L, Merrell RC, Rafiq A, Dudrick SJ, Broderick TJ.

J Surg Res. 2006 Dec;136(2):198-203. Epub 2006 Oct 11.

BACKGROUND: The objective of the study was to assess if performance of basic laparoscopic skills on a virtual reality (VR) simulator is impaired in microgravity relative to normal gravitational influences.

MATERIALS AND METHODS: Fourteen subjects with various educational backgrounds underwent basic laparoscopy skill training for five consecutive days on the ground before flying aboard NASA’s KC-135 zero-gravity laboratory. The participants performed basic laparoscopic exercises (clip applying, grasping, cutting, and suturing) on a VR laparoscopy simulator, both on the ground and during 25-s microgravity windows in parabolic flight. Skill levels after ground training were compared with skill levels in performing the same tasks in microgravity. Blinded reviewers measured the number of tasks successfully completed, tissue damage number, left and right hand path lengths during task execution, and percentage of task attempts that resulted in successful completion.

RESULTS: A significant increase in tissue injury (t test, P < 0.05) and task erosion were seen in clip applying, cutting, and grasping in microgravity (45%, 20% and 57% decrease in task attempts that resulted in a successful completion, respectively). However, there was no significant difference in the left and right hand path lengths, and the total number of tasks successfully completed on the ground versus in microgravity, for any of the four laparoscopic exercises (t test, P > 0.05).

CONCLUSION: This study demonstrates decreased efficiency and increased injury to the simulated tissues in performing laparoscopic skills during microgravity as compared to performing these skills in standard gravitational influence. Additional experiments are indicated to further develop and validate VR microgravity surgical simulation.

Objective assessment of gynecologic laparoscopic skills using the LapSimGyn virtual reality simulator.

Larsen CR, Grantcharov T, Aggarwal R, Tully A, Sørensen JL, Dalsgaard T, Ottesen B.

Surg Endosc. 2006 Sep;20(9):1460-6. Epub 2006 Jul 3.

BACKGROUND: Safe realistic training and unbiased quantitative assessment of technical skills are required for laparoscopy. Virtual reality (VR) simulators may be useful tools for training and assessing basic and advanced surgical skills and procedures. This study aimed to investigate the construct validity of the LapSimGyn VR simulator, and to determine the learning curves of gynecologists with different levels of experience.

METHODS: For this study, 32 gynecologic trainees and consultants (juniors or seniors) were allocated into three groups: novices (0 advanced laparoscopic procedures), intermediate level (>20 and <60 procedures), and experts (>100 procedures). All performed 10 sets of simulations consisting of three basic skill tasks and an ectopic pregnancy program. The simulations were carried out on 3 days within a maximum period of 2 weeks. Assessment of skills was based on time, economy of movement, and error parameters measured by the simulator.

RESULTS: The data showed that expert gynecologists performed significantly and consistently better than intermediate and novice gynecologists. The learning curves differed significantly between the groups, showing that experts start at a higher level and more rapidly reach the plateau of their learning curve than do intermediate and novice groups of surgeons.

CONCLUSION: The LapSimGyn VR simulator package demonstrates construct validity on both the basic skills module and the procedural gynecologic module for ectopic pregnancy. Learning curves can be obtained, but to reach the maximum performance for the more complex tasks, 10 repetitions do not seem sufficient at the given task level and settings. LapSimGyn also seems to be flexible and widely accepted by the users.

Improvement of surgical skills after a three-day practical course for laparoscopic surgery.

Hassan I, Koller M, Zielke A, Lehmann K, Rothmund M, Gerdes B.

Swiss Med Wkly. 2006 Sep 30;136(39-40):631-6.

OBJECTIVES: Currently, skills labs are becoming increasingly important in the field of medical education. This study aims to objectively assess psychomotor skills acquisition of residents attending a three-day laparoscopic course.

MATERIALS AND METHODS: 44 participants (test group) of the sixth practical course for Visceral Surgery of German surgical societies (Deutsche Gesellschaft für Chirurgie; DGCH and Berufsverband Deutscher Chirurgen; BDC) in Warnemuende with various degree of experience in laparoscopic surgery (18 advanced residents performing more than 50 laparoscopic operations and 26 novices performing less than 10 laparoscopic operations) and 6 consultants attending as tutors of the course (gold standard) were recruited as subjects. 20 medical students in their final year (camera holder) were chosen as a second control group (naive). Both control groups had no training during the practical course. The virtual reality simulator LapSim was used to assess laparoscopic skills of participants before and after the course. Time to complete the tasks, error score, and economy of motion parameters (path length and angular path) were analysed.

RESULTS: After the practical course the advanced participants of the test group completed the task significantly faster (p = 0.019), with smaller error score (p = 0.023), and more economy of motion [path length (p = 0.014) and angular path (p = 0.049)] than before the course. The novices of the test group and both control groups showed no significant improvement of their performance parameters (p >0.05).

CONCLUSION: A three-day practical course for laparoscopic surgery improved laparoscopic skills of residents. However, advanced residents benefit most from the course.

Virtual reality simulation can improve technical skills during laparoscopic salpingectomy for ectopic pregnancy.

Aggarwal R, Tully A, Grantcharov T, Larsen C, Miskry T, Farthing A, Darzi A.

BJOG 2006:113:1382–1387 32.

OBJECTIVES: To assess the first commercially available virtual reality (VR) simulator to incorporate procedural modules for training of inexperienced gynaecological surgeons to perform laparoscopic salpingectomy for ectopic pregnancy. DESIGN: Prospective cohort study. SETTING: Departments of surgery and gynaecology in central London teaching hospitals. SAMPLE: Thirty gynaecological surgeons were recruited to the study, and were divided into novice (<10 laparoscopic procedures), intermediate (20-50) and experienced (>100) groups.

METHODS: All subjects were orientated to the VR simulator with a basic skills task, followed by performing ten repetitions of the virtual ectopic pregnancy module, in a distributed manner.

MAIN OUTCOME MEASURES: Operative performance was assessed by the time taken to perform surgery, blood loss and total instrument path length. RESULTS: There were significant differences between the groups at the second repetition of the ectopic module for time taken (median 551.1 versus 401.2 versus 249.2 seconds, P = 0.001), total blood loss (median 304.2 versus 187.4 versus 123.3 ml, P = 0.031) and total instrument path length (median 17.8 versus 8.3 versus 6.8 m, P = 0.023). The learning curves of the experienced operators plateaued at the second session, although greater numbers of sessions were necessary for intermediate (seven) and novice (nine) surgeons to achieve similar levels of skill. CONCLUSIONS: Gynaecological surgeons with minimal laparoscopic experience can improve their skills during short-phase training on a VR procedural module. In contrast, experienced operators showed nonsignificant improvements. Thus, VR simulation may be useful for the early part of the learning curve for surgeons who wish to learn to perform laparoscopic salpingectomy for ectopic pregnancy.

The value of virtual reality-simulator training in the development of laparoscopic surgical skills.

Hart R, Doherty DA, Karthigasu K, Garry R.

J Minim Invasive Gynecol. 2006 Mar-Apr;13(2):126-33

OBJECTIVE: To determine the effectiveness of virtual reality (VR) training in improving the surgical skills of medical students and gynecologic trainees. DESIGN: A prospective observational study to assess the changes observed in objectively measured surgical performance after VR training. SETTING AND POPULATION: University teaching hospital and the laboratories of the University of Western Australia. PARTICIPANTS: Fifteen 5th-year medical students, six junior-doctor trainees (years 1-3), and eight senior trainees (years 4-6). INTERVENTIONS: Standard gynecologic procedures before and after VR training were undertaken on sheep. The procedures were video-recorded and edited to blind the scorer as to identity and seniority of the operator. The procedures were scored using a combination of operative time and penalties for surgical errors. The surgical scores were correlated with the VR scores.

MEASUREMENTS AND MAIN RESULTS: Operative skills were assessed using a combination score compiled from scores obtained while undertaking salpingectomy, salpingotomy, and tubal clipping. Virtual reality scores were also a combination score derived from summation of various computer-calculated measures of time and accuracy in undertaking two standardized exercises. RESULTS: The baseline VR scores were significantly related to the overall pre-training scores (salpingectomy p = .032). A better initial VR score was also predictive of better surgical performance. The initial VR score was also predictive of improvement observed between baseline and post-training (p = .004).

CONCLUSION: Virtual reality training is of value in improving surgical skills in the clinical environment. It appears to be of most value in the earliest stages of training. These data suggest that serious consideration should be given to incorporating VR training into the training program of obstetricians and gynecologists at an early stage.

Construct validity of the LapSim laparoscopic surgical simulator.

Woodrum DT, Andreatta PB, Yellamanchilli RK, Feryus L, Gauger PG, Minter RM.

Am J Surg. 2006 Jan;191(1):28-32.

BACKGROUND: Computer-aided simulators may increase the safety and efficiency of training in laparoscopic surgery. Before implementation of the Immersion LapSim (Gaithersburg, MD) simulator in our training curriculum, we wished to determine its construct validity (ie, whether the simulator could differentiate laparoscopic novices from trainees with greater experience).

METHODS: Subjects were medical students (MS), residents (RES), and laparoscopic faculty (FAC). Subjects performed 10 repetitions of 6 LapSim tasks. The LapSim measured performance in 6 to 10 parameters per task, and performance was compared between groups. Post hoc t tests were used to make pair-wise comparisons among the 3 groups using the Bonferroni technique. Statistical significance was set at P < .05.

RESULTS: The degree of prior laparoscopic experience was reflected in performance on at least 1 parameter for each task. Several patterns of performance between MS, RES, and FAC were observed.

CONCLUSIONS: The LapSim has performance parameters that reliably differentiate between subjects with varying laparoscopic experience. However, some performance parameters do not differentiate between groups. To accurately measure a trainee’s skill level, only parameters that sensitively measure the true level of performance should be used.

LapSim virtual reality laparoscopic simulator reflects clinical experience in German surgeons.

Langelotz C, Kilian M, Paul C, Schwenk W.

Langenbecks Arch Surg. 2005 Nov;390(6):534-7. Epub 2005 Jul 29.

BACKGROUND AND AIMS: The aim of this study was to analyze the ability of a training module on a virtual laparoscopic simulator to assess surgical experience in laparoscopy. METHODS: One hundred and fifteen participants at the 120th annual convent of the German surgical society took part in this study. All participants were stratified into two groups, one with laparoscopic experience of less than 50 operations (group 1, n=61) and one with laparoscopic experience of more than 50 laparoscopic operations (group 2, n=54). All subjects completed a laparoscopic training module consisting of five different exercises for navigation, coordination, grasping, cutting and clipping. The time to perform each task was measured, as were the path lengths of the instruments and their respective angles representing the economy of the movements. Results between groups were compared using chi(2) or Mann-Whitney U-test.

RESULTS: Group 1 needed more time for completion of the exercises (median 424 s, range 99-1,376 s) than group 2 (median 315 s, range 168-625 s) (P<0.01). Instrument movements were less economic in group 1 with larger angular pathways, e.g. in the cutting exercise (median 352 degrees , range 104-1,628 degrees vs median 204 degrees , range 107-444 degrees , P<0.01), and longer path lengths (each instrument P<0.05).

CONCLUSION: As time for completion of exercises, instrument path lengths and angular paths are indicators of clinical experience, it can be concluded that laparoscopic skills acquired in the operating room transfer into virtual reality. A laparoscopic simulator can serve as an instrument for the assessment of experience in laparoscopic surgery.

Objective assessment of laparoscopic skills using a virtual reality stimulator.

Eriksen JR, Grantcharov T.

Surg Endosc. 2005 Sep;19(9):1216-9. Epub 2005 Jul 28.

BACKGROUND: Virtual reality simulation has a great potential as a training and assessment tool of laparoscopic skills. The study was carried out to investigate whether the LapSim system (Surgical Science Ltd., Gothenburg, Sweden) was able to differentiate between subjects with different laparoscopic experience and thus to demonstrate its construct validity.

METHODS: Subjects 24 were divided into two groups: experienced (performed > 100 laparoscopic procedures, n = 10) and beginners (performed <10 laparoscopic procedures, n = 14). Assessment of laparoscopic skills was based on parameters measured by the computer system. RESULTS: Experienced surgeons performed consistently better than the residents. Significant differences in the parameters time and economy of motion existed between the two groups in seven of seven tasks. Regarding error parameters, differences existed in most but not all tasks.

CONCLUSION: LapSim was able to differentiate between subjects with different laparoscopic experience. This indicates that the system measures skills relevant for laparoscopic surgery and can be used in training programs as a valid assessment tool.

Assessing the learning curve for the acquisition of laparoscopic skills on a virtual reality simulator.

Sherman V, Feldman LS, Stanbridge D, Kazmi R, Fried GM.

Surg Endosc. 2005 May;19(5):678-82. Epub 2005 Mar 23.

BACKGROUND: The aim of this study was to develop summary metrics and assess the construct validity for a virtual reality laparoscopic simulator (LapSim) by comparing the learning curves of three groups with different levels of laparoscopic expertise.

METHODS: Three groups of subjects (‘expert’, ‘junior’, and ‘naïve’) underwent repeated trials on three LapSim tasks. Formulas were developed to calculate scores for efficiency (‘time-error’) and economy of ‘motion’ (‘motion’) using metrics generated by the software after each drill. Data (mean +/- SD) were evaluated by analysis of variance (ANOVA). Significance was set at p < 0.05.

RESULTS: All three groups improved significantly from baseline to final for both ‘time-error’ and ‘motion’ scores. There were significant differences between groups in time error performances at baseline and final, due to higher scores in the ‘expert’ group. A significant difference in ‘motion’ scores was seen only at baseline.

CONCLUSION: We have developed summary metrics for the LapSim that differentiate among levels of laparoscopic experience. This study also provides evidence of construct validity for the LapSim.

Construct validity for the LAPSIM laparoscopic surgical simulator.

Duffy A, Hogle N, McCarthy H, Lew J, Egan A, Christos P, Fowler D.

Surg Endosc. 2005 Mar;19(3):401-5. Epub 2004 Dec 23.

BACKGROUND: The skills required for laparoscopic surgery are amenable to simulator-based training. Several computerized devices are now available. We hypothesized that the LAPSIM simulator can be shown to distinguish novice from experienced laparoscopic surgeons, thus establishing construct validity.

METHODS: We tested residents of all levels and attending laparoscopic surgeons. The subjects were tested on eight software modules. Pass/fail (P/F), time (T), maximum level achieved (MLA), tissue damage (TD), motion, and error scores were compared using the t-test and analysis of variance.

RESULTS: A total of 54 subjects were tested. The most significant difference was found when we compared the most (seven attending surgeons) and least experienced (10 interns) subjects. Grasping showed significance at P/F and MLA (p < 0.03). Clip applying was significant for P/F, MLA, motion, and errors (p < 0.02). Laparoscopic suturing was significant for P/F, MLA, T, TD, as was knot error (p < 0.05). This finding held for novice, intermediate, and expert subjects (p < 0.05) and for suturing time between attending surgeons and residents (postgraduate year [PGY] 1-4) (p < 0.05).

CONCLUSIONS: LAPSIM has construct validity to distinguish between expert and novice laparoscopists. Suture simulation can be used to discriminate between individuals at different levels of residency and expert surgeons.

A virtual reality simulator for objective assessment of surgeons’ laparoscopic skill.

Hassan I, Sitter H, Schlosser K, Zielke A, Rothmund M, Gerdes B.

Chirurg. 2005 Feb;76(2):151-6.

BACKGROUND: The aim of this study was to validate computed virtual reality simulation as a tool to assess laparoscopic skills and to establish whether the simulator allows differentiating between surgeons with different laparoscopic experience.

METHODS: 27 physicians at the surgical department of the University of Marburg, Germany, with different experience in laparoscopic surgery were divided into three groups: experienced (group I), intermediate (group II), and novices (group III). Following a brief introduction to the virtual reality simulator (LapSim), each participant performed twice a training program consisting of seven tasks (examinations I and II).

RESULTS: Comparison of experienced surgeons with less experienced laparoscopic physicians showed a significant (P<0.05) superiority of group I at examinations I and II in most exercises. The groups’ difference was more obvious in examination II, since the technique was new for all participants during examination I. Tasks of low complexity in virtual reality such as camera navigation, which are performed by young, not yet responsible surgeons in real surgery, did not show significantly different results between the three groups.

CONCLUSION: Differences in laparoscopic experience can be visualised with a virtual reality simulator, and thus a simulator is helpful for assessing surgeons’ laparoscopic skills.

Laparoscopic skills training and assessment.

Aggarwal R, Moorthy K, Darzi A.

Br J Surg. 2004 Dec;91(12):1549-58.

BACKGROUND: The introduction of laparoscopic techniques to general surgery was associated with many unnecessary complications, which led to the development of skills laboratories to train novice laparoscopic surgeons. This article reviews the tools currently available for training and assessment in laparoscopic surgery.

METHODS: Medline searches were performed to identify articles with combinations of the following key words: laparoscopy, training, curriculum, virtual reality and assessment. Further articles were obtained by manually searching the reference lists of identified papers.

RESULTS: Current training involves the use of box trainers with either innate models or animal tissues; it lacks objective assessment of skill acquisition. Virtual reality simulators have the ability to teach laparoscopic psychomotor skills, and objective assessment is now possible using dexterity-based and video analysis systems.

CONCLUSION: The tools are now available for the development of a structured, competency-based, laparoscopic surgical training programme. Copyright 2004 British Journal of Surgery Society Ltd.

Surgical Skills Assessment of Applicants to General Surgery Residency

Lucian Panait, M.D., Jose M. Larios, B.A., Robert A. Brenes, M.D., Tiffany T. Fancher, M.D.,

Michael S. Ajemian, M.D., Stanley J. Dudrick, M.D., and Juan A. Sanchez, M.D., M.P.A.1

Department of Surgery, Saint Mary’s Hospital, Waterbury, Connecticut

Submitted for publication January 7, 2011

BACKGROUND. Manual skill proficiency is not currently employed in selecting residents for general surgery training programs. The study objective was to assess whether the technical skill levels of applicants to a general surgery residency program are higher than those of internal medicine residents. Material and Methods. Forty-two applicants to a community general surgery program underwent manual skill testing on interview day. Four laparoscopic tasks on a virtual reality (VR) simulator (LapSim, Goteborg, Sweden) were tested. Performance scores were computer-generated. Participants’ previous experience with other manual dexterity activities was assessed via a questionnaire. Applicants’ selfperception of their surgical skills was correlated with their skill dexterity scores on the simulator.

Candidates’ simulator scores were also compared with those of a group of internal medicine interns (n [ 9) and a group of mid-level surgical residents, PGY 2-3 (n[7). Results. Simulator scores of the applicants were significantly lower than those of mid-level surgical residents in all VR tasks (P<0.05). The internal medicine interns scored higher that the surgery candidates in three of four simulator tasks. Participation in other manual dexterity activities was not associated with increased dexterity scores. Conclusion. This study suggests that surgical dexterity levels do not correlate with the self-assessed skill levels or with previous experience with other manual dexterity activities. Moreover, there appears to be no self-selection of applicants for surgery residency based on actual surgical skills. Selection criteria for surgical training, which incorporate technical proficiency skills, may potentially better discriminate those applicants with an aptitude for a surgical specialty.