Dual energy subtraction: principles and clinical applications

Two technical solutions using single or dual shot offer different advantages and disadvantages for dual energy subtraction. The principles of these are explained and the main clinical applications with results are demonstrated. Elimination of overlaying bone and proof or exclusion of calcification are the primary aims of energy subtraction chest radiography, offering unique information in different clinical situations.

Cancer screening - principles, evaluation and implementation

Screening for malignant disease aims to reduce the population risk of impaired health due to the tumor in question. Screening does not only entail testing but covers all steps required to achieve the intended reduction in risk, from the appropriate information of the population to a suitable therapy. Screening tests are performed in individuals free or unaware of any symptoms associated with the tumor. An essential condition is a recognizable pathological abnormality, which occurs without symptoms and represents a pre-clinical, early stage of the tumor. Overdiagnosis and overtreatment have only recently been recognized as important problems of screening for malignant disease. Overdiagnosis is defined as a screening-detected tumor that would never have led to symptoms. In prostate-specific antigen (PSA) screening for prostate cancer 50 % - 70 % of screening-detected cancers represent such overdiagnoses. Similarly, in the case of mammography screening 20 % - 30 % of screening-detected breast cancers are overdiagnoses. The evaluation of screening interventions is often affected by biases such as healthy screenee effects or length and lead time bias. Randomized controlled trials are therefore needed to examine the efficacy and effectiveness of screening interventions and to define the rate of adverse outcomes such as unnecessary diagnostic evaluations, overdiagnosis and overtreatment. Unfortunately there is no independent Swiss body comparable to the National Screening Committee in the United Kingdom or the United States Preventive Services Task Force, which examines screening tests and programs and develops recommendations. Clearly defined goals, a central organization responsible for inviting eligible individuals, documentation and quality assurance and balanced information of the public are important attributes of successful screening programs. In Switzerland the establishment of such programs is hampered by the highly fragmented, Federal health system which allows patients to access specialists directly.

Vom gesellschaftlichen Engagement für den Islam zum islamischen Engagement für die Gesellschaft – Verschiebungen In Tariq Ramadans Plädoyer für eine ganzheitliche Moderne

Tariq Ramadan (born 1962) is not only a leading thinker of Islamic Reformism, but also the most prominent Muslim actor in the ongoing reconfiguration of secularity in Europe. As a guiding back- ground, the introduction to this paper establishes that by now a public role for religion in secular societies is widely accepted, albeit attached to conditions (1). After an insight into the self-posi- tioning of Ramadan, followed by a comprehensive overview of secondary literature (2), I argue for two – discernible rather than clear-cut – phases to be identified within his discourse over 16 years: Considering secular societies as devoid of values, Ramadan promotes a distinct Islamic alternative that grounds its (modern) principles (allegedly) in revelation only, and also includes specific norms of Islamic law (3). Later, the Islam to be realized consists almost exclusively of ethics – of which the basic values are shared by, and even to be established with, all members of society (4). Ramadan’s continuous plea for a holistic modernity is elaborated on at the end of this paper (5).