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Background Demographic change increases the proportion of car drivers over the age of 70. With increasing age, the likelihood of developing a form of dementia increases. In Germany, about 1.6 million people suffer from dementia. Surveys among dementia patients showed that about two-thirds said they held a valid driving licence and just under half reported still actively driving. We explored whether and to what extent motorists with dementia are putting road safety at risk and how relatives deal with the driving behaviour of their elders. Methods Semi-structured qualitative interviews were conducted with seven experts from the fields of police, gerontology and geriatrics as well as with 16 relatives of patients with different stages of dementia. All interviews were then transcribed. The analyses based on the qualitative content analysis (Mayring 2015) with MAXQDA. Results The experts regarded elderly drivers with dementia as a public health relevant safety risk. Among those elders who are affected by dementia the awareness of the problem often is limited and not rarely they are characterized by an unsafe driving style. Experts from Austria and Switzerland supported the concept of a mandatory dementia assessment for elderly drivers while experts from Germany did not. Relatives reported very similar descriptions of their elderly’s driving characteristics. Furthermore, the cognitive and motor limitations associated with dementia often are not noticed by both patients themselves and their relatives. Conclusions Representative studies are needed to test which measures, such as a mandatory dementia check from retirement age, are likely to improve the safety of older drivers with dementia. Family doctors and GPs should address and educate dementia patients in relation to their risk of accidents. Relatives should receive information material on how to communicate with their elderlys on this topic to maximize safety while avoiding conflict. Key messages The prevalence of elderly drivers with dementia is unknown. Representative studies are needed to test best practice appoaches for harm reduction in drivers with dementia.

Background Previous research shows inequalities in access to and quality of health care for migrants. We aimed to explore in what way individuals with a migrant background, who report different levels of satisfaction with healthcare, differ in terms of illness behaviour, health needs and sociodemographic characteristics. Methods In the rural Southwest of Germany, we conducted a survey with individuals who have a Turkish (n = 217) or Russian (n = 101) background and whom we could contact via cultural centres. Data were analysed using SPSS. Results In the total sample, 47,5% (Turks 53%, Russians 37%) reported always being satisfied with healthcare, 46,9% were sometimes and 5,7% never satisfied. Turks who were not always satisfied with healthcare significantly more often did not have a regular GP, and rarely visited GPs and consultants. They more often reported the need for culture sensitive print material, assistance in applying for ambulant care and culture sensitive treatment in matters such as intimacy and death and dying. Also, they more often demanded accessibility to healthcare providers with the same cultural background compared to Turks who reported more satisfaction with healthcare. Among Russians, not always being satisfied with healthcare was associated with demanding culture sensitive information on ambulant nursing care and demanding more cultural competence in providers regarding the treatment of particular diseases. Gender was not related to satisfaction with healthcare in either group. Conclusions In this sample of migrants from a rural area culture sensitive treatment was reported to be lacking especially in ambulant nursing care and end of life treatment. In view of the increasing heterogenization of society, it is necessary to address the socio-cultural needs of migrants in a home as well as in a hospital context. Therefore, culture-sensitive materials and workshops for health professionals may be useful to complement their own expertise. Key messages A low level of satisfaction with healthcare may be related to low levels of utilization. In this underserved rural area concerns regarding culture sensitive care need to be addressed.

At the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, the NIKOS system was developed for intravenous coronary angiography. To date 379 patients were examined with this system. This made it possible to exactly determine the optimal parameters of the system. The system consists of six main components. One of them, the two-line detector, is described in detail. This ionization chamber with a horizontal pixel size of 0.4 mm has a large dynamic range and low noise as well as high quantum efficiency. The fourth version of the NIKOS-detector fulfils the requirements of intravenous coronary angiography with its dynamic range of up to 300 000:1 each at four different setup modes, an equivalent photon noise of maximal 7.6, and a spatial resolution of 1.25 lp / mm in the minimum. The detective quantum efficiency reaches 85% at a readout time of 0.2 ms / line , which is faster than the necessary 0.8 ms / line . These parameters ensure that the image quality is not decreased by the detector.

Efforts have been made to image coronary arteries by non-invasive or minimally invasive methods. One method is dichromography after intravenous injection of a contrast agent. The method and the NIKOS system, which was developed for investigations of patients using this method, are described. Up to now, 379 patients were investigated. The results of a validation study are given.

The medical community is highly interested in methods for non-invasive imaging of coronary arteries. One method under development is dichromography. This method allows imaging of small fast moving objects like the coronary arteries including distal parts and sidebranches after intravenous injection of contrast material. Two images with monochromatic X-rays at energies just below and above the K-edge of iodine at 33.17 keV are simultaneously taken. After logarithmic subtraction coronary arteries down to 0.7 mm diameter with extremely low iodine concentrations of 10 mg/ml become visible. At the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY in Hamburg, Germany the system NIKOS was developed for dichromography. In this system the detector is one of the main components. This two-line detector is an ionization chamber for the two energies. The two gaps are separated by the drift cathode. A Frisch-grid for shielding the ions in a distance of 3 mm defines the conversion room. The 336 anode strips per line with a length of 56 mm in the direction of the beam are connected to the frontend electronics. The parameters of the current version of the detector in one setting are: noise equivalent of 7.6 photons, dynamic range of 300 000 : 1, readout time for the two lines (672 pixels) 0.18 ms.

Coronary angiography is the established routine imaging modality for patients with coronary artery disease. In recent years, the number of these procedures has increased remarkably. Complications associated with this invasive approach are in the range of 1.5% and the mortality is 0.1%. A further reduction of risk appears difficult to achieve because of the invasive nature of the procedure. Therefore, efforts have been made to image coronary arteries by non-invasive or minimally invasive techniques. One method under development is dichromography. This technique is based on subtraction of two images at different energies. Dichromography allows imaging of small fast-moving objects like the coronary arteries including distal parts and sidebranches after intravenous injection of a contrast material. Two images with monochromatic x-rays just below and above the absorption K-edge of the contrast agent iodine at 33.17 keV are obtained simultaneously and logarithmically subtracted. Monochromatic x-rays of sufficient intensity to visualize coronary arteries of 1 mm diameter with a low iodine mass density of are only provided by synchrotron radiation. At the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY in Hamburg, Germany the system NIKOS was developed for dichromography. This system consists of six main parts: a wiggler beamline, a two beam monochromator, a safety system, a scanning device with a seat for the patient, a two-line detector, and a computer system. After initial experimental studies with dogs, human patients have been investigated since 1990. Results of investigated patients demonstrate the feasibility and safety of the method together with high diagnostic accuracy. All cases were follow-up investigations after bypass surgery or interventions like angioplasty with a balloon catheter or rotablation with a very fast milling tool. A large-scale study has been underway since June 1997 to validate the diagnostic sensitivity and specificity compared with selective coronary angiography.

A comparison of two different multi-channel line detectors utilized in transvenous coronary angiography was performed. An Li+ drifted silicon strip detector (SSD) was tested at the SMERF facility X17B2 at the National Synchrotron Light Source (NSLS). An ionization chamber (IC) was tested at the W2 beamline at HASYLAB. Both detectors were operated in the charge-integrating mode. The main purpose was to measure and compare the Modulation Transfer Function (MTF( f )), Noise Power Spectrum (NPS( f )), Detective Quantum Efficiency (DQE( f )) in terms of spatial frequencies and the dynamic range of both detector systems. It turned out that the IC is superior to the SSD in time resolution and dynamic range at a single gain setting and has a slight advantage in the transmission of high spatial frequencies. Although for high photon flux the DQE values of the IC exceed those of the SSD, it is the reverse for low photon flux caused by a higher noise floor of the read-out electronics. This makes the SSD superior to the IC since the incident flux is limited by the tolerable entry dose to the patients. For the comparison other criteria like price, reliability, maintenance, etc., are not taken into consideration.

Worldwide several systems for Digital Subtraction Angiography in energy subtraction mode (dichromography) with synchrotron radiation are developed. Two of the systems–the system NIKOS in the Hamburger Synchrotronstrahlungslabor HASYLAB in Hamburg and the system in Brookhaven–allow investigations of patients. The aim of the work is to visualize coronary arteries down to 1 mm diameter with an iodine mass density of 1 mg/cm2, thus allowing non-invasive investigations by intravenous application of the contrast medium. The two images for subtraction are simultaneously taken with photon energies just below and above the iodine K-edge (33.17 keV) in a line scan mode. In principle the system NIKOS consists of six main parts: A 20-pole wiggler with a total length of 2.4 m and a field of 1.26 T is installed in the storage ring DORIS at DESY in Hamburg. In a two beam monochromator two bent perfect Si(111) crystals in Laue geometry are used for filtering the quasi-monochromatic beams with a bandwidth of 180 eV out of the white synchrotron radiation beam. In a safety system three independent very fast beam shutters are installed which close within less than 10 ms at any malfunction of the system. Because the line scan mode is used a scanning device moves the patient with up to 50 cm/s through the two monochromatic beams. As a detector a two-line ionization chamber with a spatial resolution of 0.4 mm is installed. The chamber has a dynamic range of 39,000:1 and reads a line within 0.73 ms. The quantum efficiency for 33 keV photons is 85%. The computer system is used for control of the system, data acquisition, image processing and presentation. Since 1990 thirty patients were studied with the system NIKOS. In all cases follow-up investigations after interventions like bypass surgery, angioplasty or rotablation were performed. Intravenous angiograms from investigations with version III of the system are presented.

A new method of X-ray polarimetry based on the photoeffect in a finely segmented MOS charge coupled device (CCD) has been applied to monochromatic synchrotron radiation at HASYLAB at DESY and to planar channeling radiation at the superconducting electron linac S-DALINAC at Darmstadt. For the smallest pixel dimensions available today (6.8×6.8 μm 2 ) an analyzing power of 10% is observed at an energy of 33 keV. In addition to events from photoeffect in the thin depleted front layer of the CCD also diffusion spread events from much more abundant conversions deeper inside the chip were utilized for polarization analysis.

BACKGROUND AND AIMS Low birth weight is associated with elevated health-care costs and adverse conditions for the newborn's start to life. A variety of health problems and an impaired potential for the infant's development are known long-term effects. Only few studies have examined the role of psychosocial and socioeconomic determinants for the incidence of low birth weight, especially in Germany. The aim of our study was to test the impact of maternal socioeconomic and psychosocial characteristics as well as health behaviour on the infant's birth weight. METHODS In an exploratory case-control study we tested whether the before mentioned potential determinants of low birth weight were observed more often among cases (birth weight

Worldwide at many synchrotron radiation laboratories different systems have been developed for digital subtraction angiography (DSA) in energy subtraction mode (dichromography). Aim of the work is to visualize coronary arteries down to 1 mm diameter with an iodine mass density of 1 mg/cm2, thus allowing non-invasive investigations by intravenous application of the contrast agent. The two images for subtraction are simultaneously taken with photon energies just below and above the iodine K-edge (33.17 keV) in a line scan mode. In the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY the system NIKOS II (NIKOS =Nicht-invasive Koronarangiographie mit Synchrotronstrahlung) consists of six main parts: the 20 pole wiggler HARWI, a two beam monochromator, a safety system, a fast scanning device, a fast low-noise two-line detector, and a computer system. In 1990 the first patients were investigated with the system NIKOS II. 30 ml of contrast medium were injected within 2 s into the vena cava superior. The scan velocity was 9 cm/s corresponding to 5.6 ms per line. The resulting images have a size of 10.0 cm (horizontal) × 12.3 cm (vertical). The pixel size in the images is 0.5 × 0.5 mm2. The radiation dose per scan (two energy images) was 25 mGy on the average. There are two main problems with the intravenous investigations using DSA in energy subtraction mode for visualization of coronary arteries: • The correct time T from the injection of the contrast material up to the beginning of the scan depends on the individual circulation time of the patient. • In intravenous investigations the small structures of interest (coronary arteries) can be superimposed by large structures (aorta, left atrium and ventricle). The images from the investigations are compared to angiograms, conventionally obtained. They have not yet the quality necessary for clinical routine but show the potential of the method if the system is optimized.

Diffraction enhanced imaging (DEI) uses refraction of x-rays at edges, which allows pronounced visualization of material borders and rejects scattering which often obscures edges and blurs images. Here, the first evidence is presented that, using DEI, a destruction-free evaluation of the quality of integration of metal implants into bone is possible. Experiments were performed in rabbits and sheep with model implants to investigate the option for DEI as a tool in implant research. The results obtained from DEI were compared to conventional histology obtained from the specimens. DE images allow the identification of the quality of ingrowth of bone into the hydroxyapatite layer of the implant. Incomplete integration of the implant with a remaining gap of less than 0.3 mm caused the presence of a highly refractive edge at the implant/bone border. In contrast, implants with bone fully grown onto the surface did not display a refractive signal. Therefore, the refractive signal could be utilized to diagnose implant healing and/or loosening.

The new X‐ray radiography imaging technique, named diffraction enhanced imaging (DEI), enables almost scatter free absorption imaging, the production of the so‐called refraction images of a sample. The images show improved contrast compared to standard imaging applications. At the HASYLAB wiggler beamline W2 at the 2nd‐generation storage ring DORIS a 5cm wide beam with an adjustable energy between 10 and 70keV is available. A Si [111] pre‐monochromator is used followed by the main monochromator using the (111) or the (333)‐reflection. Visualization of fossils, detecting internal pearl structures, monitoring of bone and cartilage and documentation of implant healing in bone are application examples at HASYLAB.

A position sensitive one‐dimensional x‐ray detector with a large dynamic range (≳214:1) for high photon fluxes with fast image recording sequence (300 ms per frame) has been developed for transvenous coronary angiography with synchrotron radiation. A position resolution of 1 LP/mm and a detection quantum efficiency (DQE) of at least 58% (for 11 000 photons per pixel) has been achieved for 33 keV photons in a Xe‐CO2 gas mixture at 20 bars. The use of Kr‐CO2 as conversion gas provides a better contrast of the weak iodine signal than Xe‐CO2 or Si, respectively, for a fraction of 2% of the second harmonics of the synchrotron beam used.

High photon fluxes are crucial in dichromatic digital subtraction angiography with line scan systems to allow for adequate image quality. To obtain images wide enough and with sufficient vertical resolution, each of the two beams used has to be at least 100 mm wide but not more than 0.5 mm high at the patient’s heart with the beam energies bracketing the iodine‐K edge at 33.17 keV. A new monochromator in Laue transmission geometry has been developed, successfully tested at beamline ID11 of the European Synchrotron Radiation Facility (ESRF) and is now in use at the angiography wiggler beamline W2 at HASYLAB. The monochromator consists of two almost identical goniometer heads which are independently controlled. Within each head a bent silicon single crystal extracts a quasimonochromatic beam and focuses it vertically to the patient thus also increasing intensity compared to an unbent crystal. With a storage ring current of 50 mA the new monochromator provides 0.8×1011 photons/mm2/s in front of the patient w...

We developed the NIKOS-system as a minimal invasive technique to image stenosis in coronary arteries after injection of iodine containing contrast material into a brachial vein. This technique uses dichromography whereby with monochromatic X-rays one image for subtraction is taken at an energy below and the other one above the K-edge of iodine. Immediately after the investigation of the patient the subtracted image is displayed under assistance of a newly designed graphical user interface (GUI). The images are automatically preprocessed by correcting for technical influences. With the help of the GUI the physician can apply different image processing algorithms on, the subtraction image to enable an accurate diagnosis. Because the GUI has a simple handling and the implemented algorithms react very rapidly, the physicians accepted the use of the GUI.

Intravenous coronary angiography with synchrotron radiation is a novel and minimally invasive technique for coronary imaging. At the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, a dedicated angiography system has been developed, which has been shown to provide detailed images of coronary artery segments. For each scan, two monochromatic X-ray images below and above the K-edge of iodine were recorded simultaneously. The two images were subtracted logarithmically to produce a maximal contrast enhancement of the iodine. To date, the procedure has been carried out on 379 outpatients. No complications occurred during or after the angiographic procedure, and hospitalization was not required in any subject. The acceptance by patient is extremely high. Five outside reviewers, blinded as to the clinical data or prior angiographic interpretation, reviewed the images for the presence or absence of 70% or more occlusion of a vessel. They reached a sensitivity of 79% and a specificity of 99%. The study has demonstrated that the synchrotron method has satisfactory sensitivity and very high specificity for severe stenoses. The new method has several advantages over magnetic resonance imaging (MRI), electron beam computed tomography (EBCT), and multi-slice computed tomography (MSCT). Neither vascular calcification (CT) nor the presence of metal stents (MRI) impairs the evaluation of perfusion of segments of the coronary arteries. Furthermore, the spatial resolution is three or four times higher using synchrotron angiography, and problems due to respiratory motion are eliminated.

Dichromography represents a digital subtraction angiography mode based on energy substraction which allows imaging of fast moving subjects like the heart. For logarithmic subtraction 2 images with X-rays just below and above the iodine K-edge (33.17 keV) are simultaneously obtained in a line scan mode. Monochromatic X-rays of sufficient intensity to visualize coronary arteries of 1 mm diameter with extremely low iodine concentrations (1 mg/cm2) after venous injection is only provided by synchrotron radiation. The system NIKOS (non-invasive coronary arteriography with synchrotron radiation) at the Deutsches Elektronen Synchrotron (DESY) consists of 6 components: a wiggler, a monochromator, a safety system, a scanning device, a detector and a computer system. After experimental studies in dogs patients are imaged since 1990. Initial results demonstrate feasibility and safety of synchrotron radiation coronary angiography. Large scale studies are designed to further evaluate sensitivity and specificity. When compact synchrotron radiation sources become available, this technique could be used for follow-up studies and for evaluation of certain high coronary risk populations.

Purpose In Canada, population-based studies report higher perinatal morbidity and mortality among Aboriginal infants than among Caucasians. The aim of this study was to compare baseline characteristics, treatment intensity, and mortality of Aboriginal versus Caucasian babies in neonatal intensive care units (NICU). Methods We examined 12,564 infants with information on ethnicity from 17 tertiary care NICUs across Canada from January 1996 to October 1997. Patient information included demographic variables, health status of infant and problems at birth, and standardized measures on illness severity (Score for Neonatal Acute Physiology Version II), and therapeutic intensity (Neonatal Therapeutic Intensity Scoring System, or NTISS). Patients were tracked until death or discharge home. Bivariate analyses and multiple linear regression analyses were conducted. Multiple births and babies with other ethnicities than Aboriginal and Caucasian were excluded. Results Aboriginal ( n = 709) and Caucasian ( n = 8333) babies did not differ in terms of Apgar score, gestational age, and intrauterine growth restriction. The mean birth weight (g) was higher among Aboriginals (2674, SD = 1.08) than among Caucasians (2535, SD = 1.04). The mean severity of illness score was higher among Caucasians (7.6, SD = 10.8 vs. 6.7, SD = 11.7). The mean treatment intensity score was higher for Caucasian infants (12.4, SD = 7.5 vs. 11.5, SD = 8.7). After adjustment for birth weight and illness severity, there were no ethnic differences in treatment score. There were no differences in mortality rate (odds ratio = 0.99, 95% confidence interval = 0.90–1.09). Conclusion Contrary to population-based samples, in this highly selected sample there were no ethnic differences in infant mortality. Treatment intensity did not differ between Aboriginal and Caucasian babies, if adjusted for confounders. Further studies should examine whether increased access to tertiary care may help to reduce infant mortality rates in the Aboriginal population.

Background and Aims In Ghana, 74/1,000 children per year die before their fifth birthday and many suffer from ill health. We explore the relative impact of genetic traits for the children’s health. Methods Within a trial on Intermittent Preventive Treatment in Infants for malaria 1,070 infants were recruited at 3 months and followed-up for 21 months in the Ashanti region. Each month standardized medical history, clinical exam and parasite density were taken. Anthropometric measures were performed every 3 months. DNA preparation and genotyping were performed according to standardized protocols. We defined “health” as a lack of malaria episodes with high parasitaemia, no episodes of anemia, no reporting of severe events like measles, accidents, burns, pneumonia, and normal WHO-growth standards during the entire study phase. We tested the association between health and genetic traits in multivariable logistic regression analyses adjusted for socioeconomic, spatial and clinical data. Results As expected, children with sickle cell trait (HbAS) were more likely to grow up healthy (OR=2.89, 95%-CI=1.59–5.24). This effect was less pronounced for carriers of HbAC (hemoglobin C). The CD74 gene SNP rs7709772AG was associated with health (OR=8.00, 95%-CI=1.76–36.29). This gene encodes for a membrane protein which is important for the regulation of immune responses against infectious diseases. α-thalassemia was not related to health in multivariate analyses. Conclusions Independently of socioeconomic and geographic factors, genetic traits that influence the risks for malaria and other infectious diseases may affect children’s health in an endemic area. This information can be relevant for the development of treatments.

Background and Aims Especially in resource poor settings measures for health promotion should be guided by evidence to channel expenditures according to populations’ health priorities. Our aim was to identify predictors for infants’ health amenable for short or midterm change to guide health policy decision making in Ghana. Methods This part of the Intermittent Preventive Treatment in Infants Trial used socioeconomic, behavioral and knowledge-related data that were collected on recruitment with interviews in the local language. Spatial data on the infants’ residence area were measured by handheld global positioning system (GPS) receiver. We tested the association between these factors and health in bivariate and multivariable analyses adjusted for each other and for genetic and clinical factors. Results In bivariate analyses, maternal age, financial status, TV, radio, refrigerator and kitchen in the house, malaria knowledge, effective protection against mosquitos and the villages’ distance to the next hospital were related to health but birth order and water source were not. In multivariate analyses, infants from well-off families were twice as likely to grow up healthy (OR=2.03, 95%–CI=1.32–3.54) than infants from poor families. Type of mosquito protection and distance to hospital also were related to health. Conclusions Independently of the child’s genetic traits, effective protection against mosquitos and access to hospital may be related to better health outcomes in this area in Ghana. Further studies should explore how access to health services can be improved in remote settings. In the meantime, investment in effective mosquito protection may support growing up healthy in Ghana.

Worldwide several systems for Digital Subtraction Angiography in energy subtraction mode (dichromography) are developed. One of the systems which allows investigations of patients - the system NIKOS in the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY is described. The system consists out of six main parts : The 20 pole wiggler HARWI in the beamline W2 of the storage ring DORIS, the two beam monochromator for the two 12.5 cm wide monochromatic X-ray beams, the safety system, the fast scanning device, the fast low-noise two-line ionization chamber and the computer system. Since 1990 patients were investigated with the system NIKOS. Aim of the work is to visualize coronary arteries down to 1 mm diameter with an iodine mass density of 1 mg/cm2, thus allowing non-invasive investigations by intravenous application of the contrast medium. The two images for subtraction are simultaneously taken with photon energies just below and above the iodine K-edge (33.17 keV) in a line scan mode. Intravenous angiograms from investigations with version III of the system NIKOS are presented and the next steps for getting an increased image quality are described.

In the near future selective coronary angiography will still be the only method to visualize the small branches of the coronary arteries. This method gives excellent images but has a certain risk for the patients with respect to morbidity (1.2 to 2.2%) and mortality (0.07 to 0.23%). That is why at different institutions worldwide1, 2, 3, 4 efforts are being made to develop a non-invasive method for coronary angiography in order to investigate ambulatory patients with mild symptoms of coronary heart disease, and to monitor disease progression routinely.

In the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY the system NIKOS II was developed for Digital Subtraction Angiography in energy subtraction mode (dichromography). Aim of the work is to visualize coronary arteries down to 1 mm diameter with an iodine mass density of 1 mg/cm2, thus allowing non-invasive investigations by intravenous application of the contrast agent. The two images for subtraction are simultaneously taken with photon energies just below and above the iodine K-edge (33.17 eV) in a line scan mode.

In modern industrialised countries chronic ischaemic heart disease is one of the major causes of death. In the course of its progression it frequently leads to acute myocardial infarction or, via different forms of heart-rhythm disturbance, to sudden heart death.