Radiology imaging delays as independent predictors of length of hospital stay for emergency medical admissions.

AIM: To investigate the extent to which the time to completion for computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound could be shown to influence the length of stay and costs incurred while in hospital, while accounting for patient acuity. MATERIALS AND METHODS: All emergency admissions, totalling 25,326 imaging investigations between 2010-2014 were evaluated. The 50(th), 75(th), and 90(th) centiles of completion times for each imaging type was entered into a multivariable truncated Poisson regression model predicting the length of hospital stay. Estimates of risk (odds or incidence rate ratios [IRRs]) of the regressors were adjusted for acute illness severity, Charlson comorbidity index, chronic disabling disease score, and sepsis status. Quantile regression analysis was used to examine the impact of imaging on total hospital costs. RESULTS: For all imaging examinations, longer hospital lengths of stay were shown to be related to delays in imaging time. Increased delays in CT and MRI were shown to be associated with increased hospital episode costs, while ultrasound did not independently predict increased hospital costs. The magnitude of the effect of imaging delays on episode costs were equivalent to some measures of illness severity. CONCLUSION: CT, MRI, and ultrasound are undertaken in patients with differing clinical complexity; however, even with adjustment for complexity, the time delay in a more expeditious radiological service could potentially shorten the hospital episode and reduce costs.

Guidance on the dental management of patients with haemophilia and congenital bleeding disorders.

Recommendations for dental preventive strategies and treatment planning were originally developed through consensus meetings by the Scottish Oral Health Group for Medically Compromised Patients and published in 2003 as a Guideline. The United Kingdom Haemophilia Centre Doctors' Organisation (UKHCDO) Dental Working Party has updated these recommendations following the AGREE II approach (www.agreetrust.org), involving a literature search, a review of national and international guidelines and after seeking the opinions of haemophilia treaters in the United Kingdom by an online survey. Where possible, evidence from the literature is graded according to the 'GRADE' system (www.bcshguidelines.com/bsch_process/evidence_levels_and_grades_of_recommendations/43_grade.html); however, overall there is a lack of robust data and most studies have methodological limitations. The objective of this guidance, which is largely consensus-based, is to assist dental practitioners in primary and secondary care to provide routine dental care for patients of all ages with congenital bleeding diatheses in order to improve overall access to dental care. The guidance may not be appropriate in all cases and individual patient circumstances may dictate an alternative approach. Date for guideline review: May 2016.

Prevalence and lifestyle determinants of the metabolic syndrome.

Participants with the metabolic syndrome are at risk of developing type 2 diabetes and coronary heart disease. The aim of this study was to determine the role of lifestyle risk factors in the development of the metabolic syndrome with particular reference to physical activity, smoking and alcohol consumption. We performed a cross sectional study of the prevalence of CVD risk factors and glucose intolerance, including type 2 diabetes involving a group of 1473 men and women were sampled from 17 general practice lists in the South of Ireland. A total of 1018 attended for screening, giving a response rate of 69%. Participants completed a detailed health and lifestyle questionnaire and provided fasting blood samples for analysis of glucose, insulin and lipids. The metabolic syndrome was defined according to the current WHO criteria. The prevalence of the metabolic syndrome was 21.0% (95% C.I. 18.7% to 24.1%). In multivariate analyses with the metabolic syndrome as the dependent variable we observed a significant, independent inverse association with physical activity level (OR = 0.60; 95% CI, 0.39-0.90 for medium and OR = 0.51; 95% CI, 0.28-0.93) for high level of activity relative to the low level of activity group). Ex-drinkers had a higher prevalence of the syndrome in multivariate analysis relative to occasional drinkers, (OR = 2.38; 95% CI, 1.08-5.26). Prevalence of the metabolic syndrome was not significantly associated with current alcohol consumption or with smoking status. These data highlight the importance of physical inactivity in the aetiology of the metabolic syndrome.

Established cardiovascular disease and CVD risk factors in a primary care population of middle-aged Irish men and women.

Contemporary Irish data on the prevalence of major cardiovascular disease (CVD) risk factors are sparse. The primary aims of this study were (1) to estimate the prevalence of major cardiovascular disease risk factors, including Type 2 Diabetes Mellitus, in the general population of men and women between the ages of 50 and 69 years; and (2) to estimate the proportion of individuals in this age group at high absolute risk of cardiovascular disease events on the basis of pre-existing cardiovascular disease or as defined by the Framingham equation. Participants were drawn from the practice lists of 17 general practices in Cork and Kerry using stratified random sampling. A total of 1018 people attended for screening (490 men, 48%) from 1473 who were invited, a response rate of 69.1%. Cardiovascular disease risk factors and glucose intolerance are common in the population of men and women aged between 50 and 69 years. Almost half the participants were overweight and a further quarter met current international criteria for obesity, one of the highest recorded prevalence rates for obesity in a European population sample. Forty per cent of the population reported minimal levels of physical activity and 19% were current cigarette smokers. Approximately half the sample had blood pressure readings consistent with international criteria for the diagnosis of hypertension, but only 38% of these individuals were known to be hypertensive. Eighty per cent of the population sample had a cholesterol concentration in excess of 5 mmol/l. Almost 4% of the population had Type 2 Diabetes Mellitus, of whom 30% were previously undiagnosed. A total of 137 participants (13.5%) had a history or ECG findings consistent with established cardiovascular disease. Of the remaining 881 individuals in the primary prevention population, a total of 20 high-risk individuals (19 male) had a risk of a coronary heart disease event > or = 30% over ten years according to the Framingham risk equation, giving an overall population prevalence of 2.0% (95% CI 1.3 - 3.0). At a risk level > or = 20% over ten years, an additional 91 individuals (8.9%) were identified. Thus a total of 24.4% of the population were at risk either through pre-existing CVD (13.5%) or an estimated 10-year risk exceeding 20% according to the Framingham risk equation (10.9%). Thus a substantial proportion of middle-aged men are at high risk of CVD. The findings emphasise the scale of the CVD epidemic in Ireland and the need for ongoing monitoring of risk factors at the population level and the need to develop preventive strategies at both the clinical and societal level.

Time-resolved grazing-incidence diffraction studies of thin films using an imaging-plate camera and focusing monochromator.

A multiple imaging-plate (IP) detector system and focusing monochromator have been developed and successfully applied to the time-resolved study of phase transitions in Langmuir-Blodgett (LB) films by grazing-incidence X-ray diffraction (GIXD). The first reported application of imaging plates to a GIXD study was carried out by our group and proved to be very successful in the determination of thin-film structure [Foran, Peng, Steitz, Barnes & Gentle (1996). Langmuir, 12, 774-777]. To extend the capabilities of this system, an IP camera was designed and built which can accommodate up to 13 IPs (40 x 20 cm) inside the vacuum chamber of the main diffractometer at the Australian Beamline at the Photon Factory. The camera allows the enclosed IPs to be successively exposed and stored inside the diffractometer for later scanning. The focusing monochromator employed in this technique combines fixed exit-beam height with sagittal focusing of the second crystal and delivers a gain in flux of >/=20 times when measured through a 0.1 x 0.1 mm aperture. The utility of the system incorporating the IP camera and the focusing monochromator has been demonstrated through the study of temperature-dependent phase transitions in LB films of metal fatty acids.

Focusing monochromator and imaging-plate camera for grazing-incidence diffraction studies of thin films.

A multiple-imaging-plate detector system and focusing monochromator have been developed and successfully applied to the time-resolved study of phase transitions in Langmuir-Blodgett films by grazing-incidence X-ray diffraction (GIXD). The monochromator described here combines fixed-exit-beam height with sagittal focusing of the second crystal. The design is similar to that of Matsushita et al. [Matsushita, Ishikawa & Oyanagi (1986). Nucl. Instrum. Methods, A246, 377-379], with the exception that the motion of the first crystal is achieved via a computer-controlled X-Y translation table rather than a set of cams. The second crystal is a ribbed Si(111) wafer mounted in a four-point bending mechanism. The first reported application of imaging plates to a GIXD study was carried out by our group and proved to be very successful in the determination of thin-film structure [Foran, Peng, Steitz, Barnes & Gentle (1996). Langmuir, 12, 774-777]. To extend the capabilities of this system, an imaging-plate camera was designed and built which can accommodate up to 13 imaging plates (40 x 20 cm) inside the vacuum chamber of the main diffractometer at the Australian Beamline at the Photon Factory.

An eight-position capillary sample spinning stage for the diffractometer at BL20B at the Photon Factory.

An eight-position capillary sample spinning stage has been developed for use in conjunction with the versatile vacuum diffractometer (BIGDIFF) at BL20B at the Photon Factory. BIGDIFF is often used in its powder diffraction mode using powders mounted in capillaries and up to eight imaging plates to record the diffraction pattern from the sample. Using the multiple spinning stage a number of diffraction patterns can be recorded on the imaging plates if the imaging-plate cassette is moved behind the Weissenberg screen to a new position after exposure of the sample to the beam. Not only is this system more efficient in terms of time saved in the pumping-down process, but also it has the advantage of allowing the diffraction patterns of standards to be recorded, thereby calibrating both the angle scale of the diffractometer and the intensity scales of the imaging plates absolutely.

Tensometry of carbon fibres and elastomers at the diffractometer at BL20B of the Photon Factory.

Two systems have been developed for the simultaneous recording of the SAXS and the WAXS patterns from carbon fibre and elastomer samples which are placed under stress. The systems have been designed to fit inside the versatile vacuum diffractometer (BIGDIFF) at the Photon Factory. In one system, use is made of the ability to move the imaging-plate cassette. In the other, use has been made of an imaging-plate changer which can deliver up to 13 plates into position with a duty cycle of about 60 s. In this case each imaging plate can record SAXS/WAXS patterns in the range 0.5-20 degrees due to the passage of the beam through the specimen which is mounted in a specially designed tensometer. Because BIGDIFF is a vacuum diffractometer and parasitic scattering is small, exposure times as short as 2 s can give acceptable SAXS/WAXS patterns. The systems have been used for the study of both the change of structure with strain, and the relaxation processes which occur as a result of the sample being strained at a fixed rate by a predetermined amount.

Synchrotron radiation study of the relation between structure and strain in polyurethane elastomers.

This paper describes a system for the study of the relation between structure and applied strain in thermoplastic polyurethane elastomers using the Australian National Beamline Facility at the Photon Factory, KEK, Tsukuba, Japan. The system uses the sagittal focusing monochromator at beamline 20B to provide a high-intensity focused beam which then falls on the specimen mounted in a miniature tensometer mounted in the unique vacuum diffractometer (BIGDIFF). Imaging plates were used to record simultaneously SAXS and WAXS patterns from the specimen at a particular strain. The change in SAXS and WAXS patterns with loading and unloading was recorded using a ten-plate imaging-plate changer.

Application of imaging-grazing-incidence X-ray diffraction and specular reflectivity to the structural investigation of quantum-confinement semiconductor devices.

X-ray reflectivity and grazing-incidence X-ray diffraction techniques have been employed to investigate the structure of quantum-well and quantum-dot semiconductor devices. This work has been performed using both laboratory and synchrotron radiation sources. The use of synchrotron radiation enabled reflectivity studies to be performed on small samples, and established the feasibility of imaging-grazing-incidence diffraction studies on quantum-confinement structures. Interdiffusion effects in quantum-well and quantum-dot structures, the disordering of overlayers grown on quantum dots, and the variation in diffraction pattern with incident angle have been observed. It is evident that X-ray reflectivity and imaging-grazing-incidence X-ray diffraction yield quite different but complementary information.