Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
1.
Surg Endosc ; 31(10): 4058-4066, 2017 10.
Article in English | MEDLINE | ID: mdl-28281111

ABSTRACT

BACKGROUND: Touch Surgery™ (TS) is a serious gaming application for cognitive task simulation and rehearsal of key steps in surgical procedures. The aim was to establish face, content, and construct validity of TS for laparoscopic cholecystectomy (LC). Furthermore, learning curves with TS and a virtual reality (VR) trainer were compared in a randomized trial. METHODS: The performance of medical students and general surgeons was compared for all three modules of LC in TS to establish construct validity. Questionnaires assessed face and content validity. For analysis of learning curves, students were randomized to train on VR or TS first, and then switched to the other training modality. Performance data were recorded. RESULTS: 54 Surgeons and 51 medical students completed the validation study. Surgeons outperformed students with TS: patient preparation (students = 45.0 ± 19.1%; surgeons = 57.3 ± 15.2%; p < 0.001), access and laparoscopy (students = 70.2 ± 10.9%; surgeons = 75.9 ± 9.7%; p = 0.008) and LC (students = 69.8 ± 12.4%; surgeons = 77.7 ± 9.6%; p < 0.001). Both groups agreed that TS was a highly useful and realistic application. 46 students were randomized for learning curve analysis. It took them 2-4 attempts to reach a 100% score with TS. Training with TS first did not improve students' performance on the VR trainer; however, students who trained with VR first scored significantly higher in module 3 of TS. CONCLUSION: TS is an accepted serious gaming application for learning cognitive aspects of LC with established construct, face, and content validity. There appeared to be a synergy between TS and the VR trainer. Therefore, the two training modalities should accompany one another in a multimodal training approach to laparoscopy.


Subject(s)
Cholecystectomy, Laparoscopic/education , Education, Medical/methods , Mobile Applications/statistics & numerical data , Surgeons/education , Virtual Reality , Adult , Clinical Competence/statistics & numerical data , Cognition/physiology , Computer Simulation , Female , Humans , Learning Curve , Male , Pilot Projects , Reproducibility of Results , Students, Medical/statistics & numerical data , Surveys and Questionnaires , Video Games
2.
Surg Endosc ; 31(5): 2155-2165, 2017 05.
Article in English | MEDLINE | ID: mdl-27604368

ABSTRACT

INTRODUCTION: Training and assessment outside of the operating room is crucial for minimally invasive surgery due to steep learning curves. Thus, we have developed and validated the sensor- and expert model-based laparoscopic training system, the iSurgeon. MATERIALS: Participants of different experience levels (novice, intermediate, expert) performed four standardized laparoscopic knots. Instruments and surgeons' joint motions were tracked with an NDI Polaris camera and Microsoft Kinect v1. With frame-by-frame image analysis, the key steps of suturing and knot tying were identified and registered with motion data. Construct validity, concurrent validity, and test-retest reliability were analyzed. The Objective Structured Assessment of Technical Skills (OSATS) was used as the gold standard for concurrent validity. RESULTS: The system showed construct validity by discrimination between experience levels by parameters such as time (novice = 442.9 ± 238.5 s; intermediate = 190.1 ± 50.3 s; expert = 115.1 ± 29.1 s; p < 0.001), total path length (novice = 18,817 ± 10318 mm; intermediate = 9995 ± 3286 mm; expert = 7265 ± 2232 mm; p < 0.001), average speed (novice = 42.9 ± 8.3 mm/s; intermediate = 52.7 ± 11.2 mm/s; expert = 63.6 ± 12.9 mm/s; p < 0.001), angular path (novice = 20,573 ± 12,611°; intermediate = 8652 ± 2692°; expert = 5654 ± 1746°; p < 0.001), number of movements (novice = 2197 ± 1405; intermediate = 987 ± 367; expert = 743 ± 238; p < 0.001), number of movements per second (novice = 5.0 ± 1.4; intermediate = 5.2 ± 1.5; expert = 6.6 ± 1.6; p = 0.025), and joint angle range (for different axes and joints all p < 0.001). Concurrent validity of OSATS and iSurgeon parameters was established. Test-retest reliability was given for 7 out of 8 parameters. The key steps "wrapping the thread around the instrument" and "needle positioning" were most difficult to learn. CONCLUSION: Validity and reliability of the self-developed sensor-and expert model-based laparoscopic training system "iSurgeon" were established. Using multiple parameters proved more reliable than single metric parameters. Wrapping of the needle around the thread and needle positioning were identified as difficult key steps for laparoscopic suturing and knot tying. The iSurgeon could generate automated real-time feedback based on expert models which may result in shorter learning curves for laparoscopic tasks. Our next steps will be the implementation and evaluation of full procedural training in an experimental model.


Subject(s)
Laparoscopy/education , Simulation Training , Clinical Competence , Feedback , Humans , Reproducibility of Results , Suture Techniques/education
3.
Eur Surg Res ; 57(1-2): 1-9, 2016.
Article in English | MEDLINE | ID: mdl-27058392

ABSTRACT

PURPOSE: The validated Objective Structured Assessment of Technical Skills (OSATS) score is used for evaluating laparoscopic surgical performance. It consists of two subscores, a Global Rating Scale (GRS) and a Specific Technical Skills (STS) scale. The OSATS has accepted construct validity for direct observation ratings by experts to discriminate between trainees' levels of experience. Expert time is scarce. Endoscopic video recordings would facilitate assessment with the OSATS. We aimed to compare video OSATS with direct OSATS. METHODS: We included 79 participants with different levels of experience [58 medical students, 15 junior residents (novices), and 6 experts]. Performance of a cadaveric porcine laparoscopic cholecystectomy (LC) was evaluated with OSATS by blinded expert raters by direct observation and then as an endoscopic video recording. Operative time was recorded. RESULTS: Direct OSATS rating and video OSATS rating correlated significantly (x03C1; = 0.33, p = 0.005). Significant construct validity was found for direct OSATS in distinguishing between students or novices and experts. Students and novices were not different in direct OSATS or video OSATS. Mean operative times varied for students (73.4 ± 9.0 min), novices (65.2 ± 22.3 min), and experts (46.8 ± 19.9 min). Internal consistency was high between the GRS and STS subscores for both direct and video OSATS with Cronbach's α of 0.76 and 0.86, respectively. Video OSATS and operative time in combination was a better predictor of direct OSATS than each single parameter. CONCLUSION: Direct OSATS rating was better than endoscopic video rating for differentiating between students or novices and experts for LC and should remain the standard approach for the discrimination of experience levels. However, in the absence of experts for direct rating, video OSATS supplemented with operative time should be used instead of single parameters for predicting direct OSATS scores.


Subject(s)
Cholecystectomy, Laparoscopic/education , Clinical Competence , Video Recording , Educational Measurement , Endoscopy, Digestive System , Humans , Operative Time
4.
Langenbecks Arch Surg ; 401(6): 893-901, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27055853

ABSTRACT

PURPOSE: Learning curves for minimally invasive surgery are prolonged since psychomotor skills and visuospatial orientation differ from open surgery and must be learned. This study explored potential advantages of sequential learning of psychomotor and visuospatial skills for laparoscopic suturing and knot tying compared to simultaneous learning. METHODS: Laparoscopy-naïve medical students were randomized into a sequential learning group (SEQ) or a simultaneous learning group (SIM). SEQ (n = 28) trained on a shoebox with direct 3D view before proceeding on a box trainer with 2D laparoscopic view. SIM (n = 25) trained solely on a box trainer with 2D laparoscopic view. Training time and number of attempts needed were recorded until a clearly defined proficiency level was reached. RESULTS: Groups were not different in total training time (SEQ 5868.7 ± 2857.2 s; SIM 5647.1 ± 2244.8 s; p = 0.754) and number of attempts to achieve proficiency in their training (SEQ 44.0 ± 17.7; SIM 36.8 ± 15.6; p = 0.123). SEQ needed less training time on the box trainer with 2D laparoscopic view than did SIM (SEQ 4170.9 ± 2350.8 s; SIM 5647.1 ± 2244.8 s; p = 0.024), while the number of attempts here was not different (SEQ 29.9 ± 14.1; SIM 36.8 ± 15.6; p = 0.097). SEQ was faster in the first attempts on the shoebox (281.9 ± 113.1 s) and box trainer (270.4 ± 133.1 s) compared to the first attempt of SIM on the box trainer (579.4 ± 323.8 s) (p < 0.001). CONCLUSION: In the present study, SEQ was faster than SIM at the beginning of the learning curve. SEQ did not reduce the total training time needed to reach an ambitious proficiency level. However, SEQ needed less training on the box trainer; thus, laparoscopic experience can be gained to a certain extent with a simple shoebox.


Subject(s)
Laparoscopy/education , Psychomotor Performance , Spatial Processing , Suture Techniques/education , Clinical Competence , Female , Humans , Learning Curve , Male , Models, Anatomic , Prospective Studies , Simulation Training
5.
Int J Comput Assist Radiol Surg ; 11(12): 2295-2301, 2016 Dec.
Article in English | MEDLINE | ID: mdl-26872808

ABSTRACT

AIM: To analyze factors influencing the learning of surgical liver anatomy in a computer-based teaching module (TM). METHODS: Medical students in their third to fifth year of training (N [Formula: see text] 410) participated in three randomized trials, each with a different primary hypothesis, comparing two- (2D) and three-dimensional (3D) presentation modes in a TM for surgical liver anatomy. Computed tomography images were presented according to the study and allocation group. Students had to answer eleven questions on surgical liver anatomy and four evaluative questions. Scores and time taken to answer the questions were automatically recorded. Since the three studies used the same 15 questions in the TM, a pooled analysis was performed to compare learning factors across studies. RESULTS: 3D groups had higher scores (7.5 ± 1.7 vs. 5.6 ± 2.0; p < 0.001) and needed less time (503.5 ± 187.4 vs. 603.1 ± 246.7 s; p < 0.001) than 2D groups. Intensive training improved scores in 2D (p < 0.001). Men gave more correct answers than women, independent of presentation mode (7.2 ± 2.0 vs. 6.5 ± 2.1; p [Formula: see text] 0.003). An overall association was found between having fun and higher scores in 11 anatomical questions (p < 0.001). In subgroup analysis, 3D groups had more fun than 2D groups (84.7 vs. 65.1 %; p < 0.001). If given the option, more students in the 2D groups (58.9 %) would have preferred a 3D presentation than students in the 3D group (35.9 %) would have preferred 2D (p  < 0.001). CONCLUSION: 3D was superior to 2D for learning of surgical liver anatomy. With training 2D showed similar results. Fun and gender were relevant factors for learning success.


Subject(s)
Biliary Tract Surgical Procedures/education , Computer-Assisted Instruction , Imaging, Three-Dimensional , Liver/surgery , Educational Measurement , Female , Humans , Liver/anatomy & histology , Male , Tomography, X-Ray Computed
6.
Trials ; 17: 14, 2016 Jan 07.
Article in English | MEDLINE | ID: mdl-26739331

ABSTRACT

BACKGROUND: Laparoscopy training has become an integral part of surgical education. Suturing and knot tying is a basic, yet inherent part of many laparoscopic operations, and should be mastered prior to operating on patients. One common and standardized suturing technique is the C-loop technique. In the standard training setting, on a box trainer, the trainee learns the psychomotor movements of the task and the laparoscopic visuospatial orientation simultaneously. Learning the psychomotor and visuospatial skills separately and sequentially may offer a more time-efficient alternative to the current standard of training. METHODS: This is a monocentric, two-arm randomized controlled trial. The participants are medical students in their clinical years (third to sixth year) at Heidelberg University who have not previously partaken in a laparoscopic training course lasting more than 2 hours. A total of 54 students are randomized into one of two arms in a 1:1 ratio to sequential learning (group 1) or control (group 2). Both groups receive a standardized introduction to the training center, laparoscopic instruments, and C-loop technique. Group 1 learn the C-loop using a transparent shoebox, thus only learning the psychomotor skills. Once they reach proficiency, they then perform the same knot tying procedure on a box trainer with standard laparoscopic view, where they combine their psychomotor skills with the visuospatial orientation inherent to laparoscopy. Group 2 learn the C-loop using solely a box trainer with standard laparoscopic view until they reach proficiency. Trainees work in pairs and time is recorded for each attempt. The primary outcome is mean total training time for each group. Secondary endpoints include procedural and knot quality subscore differences. Tertiary endpoints include studying the influence of gender and video game experience on performance. DISCUSSION: This study addresses whether the learning of the psychomotor and visuospatial aspects of laparoscopic suturing and knot tying is optimal sequentially or simultaneously, by assessing total training time, procedural, and knot quality differences between the two groups. It will improve the efficiency of future laparoscopic suturing courses and may serve as an indicator for laparoscopic training in a broader context, i.e., not only for suturing and knot tying. TRIAL REGISTRATION: This trial was registered on 12 August 2015 with the trial registration number DRKS00008668 .


Subject(s)
Clinical Competence , Clinical Protocols , Laparoscopy/education , Learning , Psychomotor Performance , Suture Techniques , Ethics, Medical , Humans , Students, Medical
7.
Trials ; 15: 137, 2014 Apr 23.
Article in English | MEDLINE | ID: mdl-24754961

ABSTRACT

BACKGROUND: Laparoscopy training courses have been established in many centers worldwide to ensure adequate skill learning before performing operations on patients. Different training modalities and their combinations have been compared regarding training effects. Multimodality training combines different approaches for optimal training outcome. However, no standards currently exist for the number of trainees assigned per workplace. METHODS: This is a monocentric, open, three-arm randomized controlled trial. The participants are laparoscopically-naive medical students from Heidelberg University. After a standardized introduction to laparoscopic cholecystectomy (LC) with online learning modules, the participants perform a baseline test for basic skills and LC performance on a virtual reality (VR) trainer. A total of 100 students will be randomized into three study arms, in a 2:2:1 ratio. The intervention groups participate individually (Group 1) or in pairs (Group 2) in a standardized and structured multimodality training curriculum. Basic skills are trained on the box and VR trainers. Procedural skills and LC modules are trained on the VR trainer. The control group (Group C) does not receive training between tests. A post-test is performed to reassess basic skills and LC performance on the VR trainer. The performance of a cadaveric porcine LC is then measured as the primary outcome using standardized and validated ratings by blinded experts with the Objective Structured Assessment of Technical Skills. The Global Operative Assessment of Laparoscopic Surgical skills score and the time taken for completion are used as secondary outcome measures as well as the improvement of skills and VR LC performance between baseline and post-test. Cognitive tests and questionnaires are used to identify individual factors that might exert influence on training outcome. DISCUSSION: This study aims to assess whether workplaces in laparoscopy training courses for beginners should be used by one trainee or two trainees simultaneously, by measuring the impact on operative performance and learning curves. Possible factors of influence, such as the role of observing the training partner, exchange of thoughts, active reflection, model learning, motivation, pauses, and sympathy will be explored in the data analysis. This study will help optimize the efficiency of laparoscopy training courses. TRIAL REGISTRATION NUMBER: DRKS00004675.


Subject(s)
Cholecystectomy, Laparoscopic/education , Education, Medical, Graduate/methods , Internship and Residency , Research Design , Workplace , Animals , Clinical Competence , Cognition , Computer Simulation , Computer-Assisted Instruction , Curriculum , Educational Status , Germany , Hospitals, University , Humans , Internet , Learning Curve , Models, Animal , Prospective Studies , Surveys and Questionnaires , Swine , Task Performance and Analysis , Time Factors
8.
Inorganica Chim Acta ; 401: 64-69, 2013 May 24.
Article in English | MEDLINE | ID: mdl-23626375

ABSTRACT

We have synthesized an oxaliplatin derivative using N,N'-dimethyl-1,2-diaminocyclohexane (Me2dach) as the diamine ligand. The complex (S,R,R,S)-Pt(Me2dach)(oxalate), where S,R,R,S represents the chiralities at N,C,C,N, respectively, was prepared and characterized by 1H NMR spectroscopy, COSY, NOESY, and HMQC. Oxaliplatin reacts with N-acetylmethionine (N-AcMet) to form [Pt(dach)(N-AcMet-S)2] and [Pt(dach)(N-AcMet-S,N)], with the former favored at higher molar ratios of N-AcMet. In contrast, Pt(Me2dach)(oxalate) reacts to form [Pt(Me2dach)(N-AcMet-S,O)]+ even in the presence of excess N-AcMet. Molecular mechanics calculations are consistent with significant steric clashes in models of [Pt(Me2dach)(N-AcMet-S)2]. When N-AcMet was reacted with an excess of each platinum complex, the rate of N-AcMet decrease was very similar for both complexes. Thus, the methyl groups at the nitrogen atoms had little to no effect on the addition of the sulfur atom of a single N-acetylmethionine, but they prevented chelation of the amide nitrogen or coordination of a second N-acetylmethionine residue.

SELECTION OF CITATIONS
SEARCH DETAIL
...