A Bernstein-Bézier Based Approach to Soft Tissue Simulation

This paper discusses a Finite Element approach for volumetric soft tissue modeling in the context of facial surgery simulation. We elaborate on the underlying physics and address some computational aspects of the finite element discretization.
In contrast to existing approaches speed is not our first concern, but we strive for the highest possible accuracy of simulation. We therefore propose an extension of linear elasticity towards incompressibility and nonlinear material behavior, in order to describe the complex properties of human soft tissue more accurately. Furthermore, we incorporate higher order interpolation functions using a Bernstein-Bézier formulation, which has various advantageous properties, such as its integral polynomial form of arbitrary degree, efficient subdivision schemes, and suitability for geometric modeling and rendering. In addition, the use of tetrahedral Finite Elements does not put any restriction on the geometry of the simulated volumes.
Experimental results obtained from a synthetic block of soft tissue and from the Visible Human Data Set illustrate the performance of the envisioned model.     

Ozone in oral surgery ‐ current status and prospects

Ozone has proved to be an effective water disinfectant for dental treatment units. Using this technique it is now possible to keep the water in a dental treatment unit low in germ count or germ‐free. Growth of germs does not occur during the routine intermissions in the daily activities of a dental office. Since ozonated water is germ‐free, it can be used in dental surgery as a coolant for burrs and for rinsing wounds. Thus, properties of ozone relevant to medicine can be utilized in the field of dental, oral and maxillomandibular surgery.     

全高清手术示教系统在数字化医院中的应用

本文主要介绍了现代化数字医院中手术示教系统的设计，侧重阐述了其设计依据、原则、设备选型、功能及具体应用的特点。     

Influence of Per-Operative Serum on Tumour Cell Adhesion in Vitro

In case of massive tissue damage, the ensuing inflammatory reaction produces a potentially lethal cocktail of active mediators. Beside the influence of these local factors on local tumour recurrence, we hypothesize that during surgery systemically produced mediators are potential stimulators of tumour cell adhesion as well. The aim of this study was to investigate the influence of serum samples, obtained at eight different time periods before, during, and after surgery on the interaction between human colon carcinoma cells and mesothelial cells.

In the control situation, the average adhesion of the Caco-2 cells to the mesothelial monolayers was 29%. No enhancement in adhesion was observed after incubation of the mesothelial cells with the pre- or postoperative serum of the patients.

This study suggests that systemic factors produced directly after surgery are not influencing tumour adhesion to mesothelial monolayers. Therefore, local tumour recurrence is probably only influenced by locally produced factors.     

2种手术方法治疗腮腺浅叶良性肿瘤的比较观察

目的研究保留部分腮腺浅叶腺体与腮腺浅叶全切术这2种手术方式在腮腺浅叶良性肿瘤治疗后的临床效果。方法选择90例腮腺浅叶肿瘤中,60例行肿瘤及部分浅叶腺体切除面神经解剖术,30例行肿瘤及全部浅叶切除。比较术后涎痿,面瘫及复发情况。结果 2种手术方式复发率分别为6.3%(12/60),5.0%(6/30),涎瘘率接近,术后l～12周面瘫率及恢复率类似。结论 2种手术方式对腮腺浅叶肿瘤的临床治疗效果没有明显的影响。     

Improving cardiac surgical care: A work systems approach

Over the past 50 years, significant improvements in cardiac surgical care have been achieved. Nevertheless, surgical errors that significantly impact patient safety continue to occur. In order to further improve surgical outcomes, patient safety programs must focus on rectifying work system factors in the operating room (OR) that negatively impact the delivery of reliable surgical care. The goal of this paper is to provide an integrative review of specific work system factors in the OR that may directly impact surgical care processes, as well as the subsequent recommendations that have been put forth to improve surgical outcomes and patient safety. The important role that surgeons can play in facilitating work system changes in the OR is also discussed. The paper concludes with a discussion of the challenges involved in assessing the impact that interventions have on improving surgical care. Opportunities for future research are also highlighted throughout the paper.     

Tensile forces induced in collagen by means of electromechanochemical transductive coupling

Electric fields are applied across a charged collagen membrane which supports a gradient in neutral salt concentration. Experiments over a wide range of concentration have shown that isometric tensile force densities larger than that of striated muscle can be induced by the applied field. The experimental results, together with the trends predicted by a theoretical model, suggest that the forces result from field-induced changes in intramembrane salt concentration which in turn modify the internal double layer repulsive forces between charged fibrils. Characteristic times for this electromechanochemical transduction process are examined in terms of the various rate limiting processes of importance.     

《中医外科学常见病诊疗指南》制定的方法学研究

在中医外科常见病诊疗指南的制定的方法学研究中,为了在证据等级极低的情况下保证指南的科学性与实用性,我们提出了以GRADE证据分级和推荐意见标准为基础,以古代文献、专家经验为参考,以专家共识为依据,最后综合考量的方法学思路制定指南。这样既遵循了循证医学的理念,突出了古代文献、专家经验在中医外科临床中的重要性,又保持了中医外科学的特点。     

Improving performance reliability in surgical systems

Health care has evolved rapidly to meet the medical demands of society, but not to meet the demands of consistent operational safety. In other high risk domains in which the consequences of systems failure are unacceptable, organisational and operational work systems have been developed to deliver consistent, high-quality, failure-free performance. In this paper we review contributions to a special issue of Cognition, Technology and Work on ‘Enhancing Surgical Systems’. We consider their implications for improving the reliability of care processes in light of theoretical developments in the area of high-reliability organisations and resilience engineering. Health care must move from reactive safety cultures to be more proactively resilient to the continual threats posed by complexity in clinical care processes and the multi-professional hospital environment. Our analysis emphasises the importance of team working for reliable operational performance. A schematic framework to illustrate how safety interventions in surgery might cohere within an organisational strategy for achieving high-reliability is proposed. The implications for continuous quality improvement and effective regulation of system safety over differing time scales and organisational levels are discussed.