OSIRIS-REx is the first NASA mission to return a sample of an asteroid to Earth. Navigation and flight dynamics for the mission to acquire and return a sample of asteroid 101955 Bennu establish many ...firsts for space exploration. These include relatively small orbital maneuvers that are precise to ∼1 mm/s, close-up operations in a captured orbit about an asteroid that is small in size and mass, and planning and orbit phasing to revisit the same spot on Bennu in similar lighting conditions. After preliminary surveys and close approach flyovers of Bennu, the sample site will be scientifically characterized and selected. A robotic shock-absorbing arm with an attached sample collection head mounted on the main spacecraft bus acquires the sample, requiring navigation to Bennu’s surface. A touch-and-go sample acquisition maneuver will result in the retrieval of at least 60 grams of regolith, and up to several kilograms. The flight activity concludes with a return cruise to Earth and delivery of the sample return capsule (SRC) for landing and sample recovery at the Utah Test and Training Range (UTTR).
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Simulators are being used more and more for teaching and testing laparoscopic skills. However, it has yet to be firmly established that simulator performance reflects operative laparoscopic skill. ...The study reported here was designed to test the hypothesis that laparoscopic simulator performance predicts intraoperative laparoscopic skill.
A review of our prospectively maintained database identified 40 subjects who underwent Fundamentals of Lapraoscopic Surgery (FLS) skills testing and objective intraoperative assessments within the same 6-month period. Subjects consisted of 22 novice (postgraduate year PGY 1-2), 10 intermediate (PGY 3-4), and 8 experienced (PGY 5, fellows, and attendings) laparoscopic surgeons. Laparoscopic performance was objectively assessed in the operating room using the previously validated Global Operative Assessment of Laparoscopic Skill (GOALS). Analysis of variance (ANOVA) was used to compare mean FLS scores and mean GOALS scores across experience levels. The relationship between individual FLS scores and GOALS scores was assessed with linear regression analysis. A multivariate analysis evaluated FLS score and surgeon experience as predictors of intraoperative GOALS score. A receiver-operator curve (ROC) was constructed in order to define an FLS cutoff score that predicts intraoperative performance at or above the level of experienced surgeons. Significance was defined as p < 0.05.
Mean FLS scores and mean GOALS scores increased with increasing experience. Individual FLS scores correlated significantly with intraoperative GOALS scores (0.77, p < 0.001). Multivariate analysis confirmed that FLS score is an independent predictor of intraoperative GOALS scores. The ROC identified an FLS cutoff score of 70 with optimal sensitivity (91%) and specificity (86%) for predicting a GOALS score at or above the level of experienced surgeons.
In this study sample, FLS simulator scores were independently predictive of intraoperative laparoscopic performance as measured by GOALS. More precisely, an FLS cutoff score of 70 optimized sensitivity and specificity for expert intraoperative performance. A larger prospective study is justified to validate these findings.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The antiphospholipid syndrome (APLS) is a complex autoimmune disease often connected to systemic lupus erythematodes. Main features are thromboses, fetal loss and specific antibodies. The involved ...autoantibodies are directed against plasma proteins such as beta2glycoprotein1 (β2GPI) or prothrombin which depend on negatively charged phospholipids. Direct antibodies against phospholipids are of no importance for APLS. Clotting tests such as activated partial thromboplastin time or diluted Russell’s viper venom test (dRVVT) can show a prolonged time for coagulation despite a prothrombotic state in vivo but the investigator needs awareness about disturbing phospholipid sources and other influential factors. Enzyme linked immuno sorbent assay tests for antibodies against cardiolipin, β2GPI and prothrombin are valuable solid phase tests with different specificity. Antiphospholipid, anticardiolipin or lupus anticoagulant are misnomers in connection with APLS. They are preserved as a reminiscence of the pioneering work on the way to the still not exactly revealed basics of APLS. Valve operations in APLS patients seem to be rare; a meta-analysis of 57 cases proves that the perioperative management is, at the moment, an empirical approach with high morbidity and mortality in these young patients.
The McGill Inanimate System for Training and Evaluation of Laparoscopic Skills (MISTELS) is a series of five tasks with an objective scoring system. The purpose of this study was to estimate the ...interrater and test-retest reliability of the MISTELS metrics and to assess their internal consistency.
To determine interrater reliability, two trained observers scored 10 subjects, either live or on tape. Test-retest reliability was assessed by having 12 subjects perform two tests, the second immediately following the first. Interrater and test-retest reliability were assessed using intraclass correlation coefficients. Internal consistency between tasks was estimated using Cronbach's alpha.
The interrater and test-retest reliabilities for the total scores were both excellent at 0.998 95% confidence interval (CI), 0.985-1.00 and 0.892 (95% CI, 0.665-0.968), respectively. Cronbach's alpha for the first assessment of the test-retest was 0.86.
The MISTELS metrics have excellent reliability, which exceeds the threshold level of 0.8 required for high-stakes evaluations. These findings support the use of MISTELS for evaluation in many different settings, including residency training programs.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The McGill Inanimate System for Training and Evaluation of Laparoscopic Skills (MISTELS) was developed to assess laparoscopic skills and to score them objectively. This system has been described ...previously. The purpose of the current study was to determine a pass/fail threshold.
In this study, 165 individuals were tested and grouped according to their clinical competency in laparoscopic surgery. The noncompetent group consisted of medical students and surgical residents in their first 2 years of training (n = 83). The competent group consisted of chief general surgical residents in their last year of training, laparoscopy fellows, and practicing laparoscopic surgeons (n = 82). The Mann-Whitney U test was used to evaluate differences in task performance between the two groups.
There was a significant difference in total scores and individual MISTELS task scores between the noncompetent and competent laparoscopic surgeons (189 vs 372.5; p <0.0001). By setting specific pass/fail total score thresholds (cutoff scores), competent surgeons can be discriminated from noncompetent surgeons.
An objective pass/fail evaluation can be given to individuals tested with the MISTELS system.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The purpose of this study is to assess how subjective evaluation (heartburn, dysphagia, quality of life, and satisfaction) correlates with objective data after Heller myotomy and Dor fundoplication ...for achalasia.
A total of 53 consecutive patients with achalasia undergoing laparoscopic Heller myotomy and Dor fundoplication were studied prospectively. Subjective evaluation was done preop and postop using the Gastroesophageal Reflux Disease Health-Related Quality of Life instrument (GERD-HRQL; 0 = best, 45 = worse), 4-point dysphagia and heartburn scales (0 = best, 3 = worst), patient satisfaction scale (0 = very satisfied, 5 = incapacitated), and the SF-12 general health-related quality-of-life score. At 3 months postop, patients were asked to undergo objective evaluation with 24-h pH testing, manometry, and endoscopy. Data are expressed as median (interquartile range) and analyzed by Wilcoxon signed rank test or Mann-Whitney U test.
Forty-nine patients were more than 3 months postsurgery. Comparing preop to postop, improvements were found in dysphagia 3 (2-3) to 0 (0-1), heartburn 1 (0-2) to 0 (0-1), GERD-HRQL 13.5 (6.3-22.5) to 2 (0-5), satisfaction 3 (3-4) to 1 (0-1), and SF-12 mental component summary 46 (37-56) to 58 (50-59) and physical component summary 46 (36-53) to 55 (48-56) scores (p < 0.0001 for all). Thirty-eight patients (78%) agreed to undergo objective testing, and complete data were available for 32 (65%). Four of 32 patients (12.5%) had evidence of reflux based on 24-h pH testing. Of nine patients with GERD-HRQL >5, only two had positive pH test (22%). Of 23 patients with GERD-HRQL <5, two had positive pH test (7%). Of four tested patients with moderate to severe heartburn, two had an abnormal pH test. There was no significant relationship between GERD-HRQL score and pH test results. Lower esophageal sphincter pressure (LESP) decreased from 24 (16-35) to 13 mmHg (11-17) (p < 0.001). There was no relationship between dysphagia score and postop absolute LESP or a decrease in LESP after operation.
Laparoscopic Heller myotomy and Dor fundoplication is an effective treatment for achalasia. Subjective evaluation can document patient satisfaction and health-related quality of life but does not accurately reflect postop reflux. Twenty-four-hour pH study is required to accurately assess reflux disease.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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.
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.
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.
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.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The psychomotor challenges inherent in laparoscopic surgery are evident by the steep procedural "learning curves" documented throughout the literature. Few methods have been described to evaluate ...learning curves. The cumulative summation (CUSUM) method is a criterion-based evaluation of the learning process. The purpose of this study is to describe the CUSUM learning curves for a simple task for individuals and for a group of novice laparoscopists.
Sixteen medical students undertook four weekly sessions of 10 laparoscopic pegboard transfers in the MISTELS system. Their performance was scored and recorded for each trial. CUSUM learning curves were constructed based on the goal of achieving mean scores for senior, intermediate, or junior laparoscopists >or=95% of the time.
Based on senior criteria, one student achieved the goal by the 40th peg transfer trial. Based on intermediate criteria, three students achieved the goal by their 40th trial (trials 21 and 36), and for junior criteria, 10 students achieved the acceptable success rate by their 40th trial (range, 26-40).
CUSUM analysis suggests criterion-based practice is useful for novice laparoscopists. It allows educators to track the progress of an individual toward target criteria for each MISTELS task, to more logically allocate time for training and set attainable goals, to objectively evaluate trainee acquisition of basic laparoscopic skills, and to identify trainees who need remediation.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The McGill Inanimate System for Training and Evaluation of Laparoscopic Skills (MISTELS) consists of a series of five laparoscopic exercises performed in an endotrainer box. MISTELS has been ...validated for use in both training and evaluation of general surgery residents in fundamental laparoscopic skills. The purpose of this study was to demonstrate the construct validity of MISTELS for urology residents.
Seventeen participants were evaluated during performance of the five MISTELS tasks (peg transfer, pattern cutting, ligating loop, and suturing with extracorporeal and intracorporeal knots) using the standardized scoring system, which rewards both speed and precision. Participants included 13 urology residents (PGY 1-5), 1 fellow, and 3 urologists experienced in laparoscopy. Results are expressed as median (range). The Mann-Whitney U-test was used to compare MISTELS scores for 9 novice (PGY 1-4) and 8 experienced urologists (PGY 5-attending). P < 0.05 was considered statistically significant.
The median MISTELS total normalized score for novices was 52.3 (range 15-68.9) compared with 71.7 (range 56.3-82.9) for experienced urologists (P = 0.007). Although the experienced group achieved higher scores in all five individual tasks, statistically significant differences were demonstrated for the peg transfer and intracorporeal suture tasks only.
These data provide evidence for construct validity of the MISTELS system for urology residents.
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