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21.

Background

There is an increasing need for efficient training simulators to teach advanced laparoscopic skills beyond those imparted by a box trainer. In particular, force-based or haptic skills must be addressed in simulators, especially because a large percentage of surgical errors are caused by the over-application of force. In this work, the efficacy of a novel, salient haptic skills simulator is tested as a training tool for force-based laparoscopic skills.

Methods

Thirty novices with no previous laparoscopic experience trained on the simulator using a pre-test–feedback–post-test experiment model. Ten participants were randomly assigned to each of the three salient haptic skills—grasping, probing, and sweeping—on the simulator. Performance was assessed by comparing force performance metrics before and after training on the simulator.

Results

Data analysis indicated that absolute error decreased significantly for all three salient skills after training. Participants also generally decreased applied forces after training, especially at lower force levels. Overall, standard deviations also decreased after training, suggesting that participants improved their variability of applied forces.

Conclusions

The novel, salient haptic skills simulator improved the precision and accuracy of participants when applying forces with the simulator. These results suggest that the simulator may be a viable tool for laparoscopic force skill training. However, further work must be undertaken to establish full validity. Nevertheless, this work presents important results toward addressing simulator-based force-skills training specifically and surgical skills training in general.  相似文献   
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Collecting system duplication is marked by a variety of clinical syndromes. Bilateral and obstructed duplicated systems, particularly with asymmetric levels of duplication, are rare and typically due to ureteric bud development anomalies. The infrequency with which this condition exists makes it a formidable challenge for physicians and patients. To our knowledge, we present the first case report of bilateral obstruction of bilaterally duplicated collecting systems. In our case, a 52-year-old male complaining of low back pain, constipation, urinary urgency and hematuria was found to have bilateral obstructing stones as well as asymmetrical bilateral collecting system duplication. We discuss the natural history of this condition, its consequences and identification.Key Words: Congenital abnormalities, Kidney tubules, Ureteral obstruction, Vesico-ureteral reflux  相似文献   
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Forensic odontologists play an important role locally and nationally in assisting in the identification of the victims of mass fatality incidents, whether natural or human-made. With the recent passage of legislation by Congress identifying dentists as a first-responder resource, knowledge of their expanding role in disaster response is particularly important. The purpose of this article is to describe the forensic dental course being taught at Creighton University School of Dentistry in Omaha, Nebraska, as a model for providing a fundamental education in forensic dentistry and disaster preparedness at the predoctoral dental level. This model is designed to 1) provide students with a broad view of forensic odontology; 2) give them a functional knowledge of the tools and techniques of the modern forensic dentist; 3) provide basic knowledge of their potential role in disaster preparedness and response; and 4) encourage students to pursue further forensic education, become active in national forensic organizations, and get involved in disaster preparedness/response in their home communities following graduation. This article includes lecture topics, demonstrations, and hands-on exercises being used at Creighton to teach students the fundamentals of forensic odontology and disaster preparedness.  相似文献   
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BackgroundCharcot neuroarthropathy is a morbid and expensive complication of diabetes that can lead to lower extremity amputation. Current treatment of unstable midfoot deformity includes lifetime limb bracing, primary transtibial amputation, or surgical reconstruction of the deformity. In the absence of a widely adopted treatment algorithm, the decision to pursue more costly attempts at reconstruction in the United States continues to be driven by surgeon preference.Questions/purposesTo examine the cost effectiveness (defined by lifetime costs, quality-adjusted life-years [QALYs] and incremental cost-effectiveness ratio [ICER]) of surgical reconstruction and its alternatives (primary transtibial amputation and lifetime bracing) for adults with diabetes and unstable midfoot Charcot neuroarthropathy using previously published cost data.MethodsA Markov model was used to compare Charcot reconstruction and its alternatives in three progressively worsening clinical scenarios: no foot ulcer, uncomplicated (or uninfected) ulcer, and infected ulcer. Our base case scenario was a 50-year-old adult with diabetes and unstable midfoot deformity. Patients were placed into health states based on their disease stage. Transitions between health states occurred annually using probabilities estimated from the evidence obtained after systematic review. The time horizon was 50 cycles. Data regarding costs were obtained from a systematic review. Costs were converted to 2019 USD using the Consumer Price Index. The primary outcomes included the long-term costs and QALYs, which were combined to form ICERs. Willingness-to-pay was set at USD 100,000/QALY. Multiple sensitivity analyses and probabilistic analyses were performed to measure model uncertainty.ResultsThe most effective strategy for patients without foot ulcers was Charcot reconstruction, which resulted in an additional 1.63 QALYs gained and an ICER of USD 14,340 per QALY gained compared with lifetime bracing. Reconstruction was also the most effective strategy for patients with uninfected foot ulcers, resulting in an additional 1.04 QALYs gained, and an ICER of USD 26,220 per QALY gained compared with bracing. On the other hand, bracing was cost effective in all scenarios and was the only cost-effective strategy for patents with infected foot ulcers; it resulted in 6.32 QALYs gained and an ICER of USD 15,010 per QALY gained compared with transtibial amputation. As unstable midfoot Charcot neuroarthropathy progressed to deep infection, reconstruction lost its value (ICER USD 193,240 per QALY gained) compared with bracing. This was driven by the increasing costs associated with staged surgeries, combined with a higher frequency of complications and shorter patient life expectancies in the infected ulcer cohort. The findings in the no ulcer and uncomplicated ulcer cohorts were both unchanged after multiple sensitivity analyses; however, threshold effects were identified in the infected ulcer cohort during the sensitivity analysis. When the cost of surgery dropped below USD 40,000 or the frequency of postoperative complications dropped below 50%, surgical reconstruction became cost effective.ConclusionsSurgeons aiming to offer both clinically effective and cost-effective care would do well to discuss surgical reconstruction early with patients who have unstable midfoot Charcot neuroarthropathy, and they should favor lifetime bracing only after deep infection develops. Future clinical studies should focus on methods of minimizing surgical complications and/or reducing operative costs in patients with infected foot ulcers.Level of EvidenceLevel II, economic and decision analysis.  相似文献   
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