A geographical study of thyroid cancer incidence in north-west England following the Windscale nuclear reactor fire of 1957.

The Windscale nuclear reactor fire at Sellafield, United Kingdom, in October 1957 led to an uncontrolled release of iodine-131 (radioactive half-life, 8 d) into the atmosphere. Contamination from the accident was most pronounced in the counties of Cumbria and Lancashire, north-west England. Radioiodine concentrates in the thyroid gland producing an excess risk of thyroid cancer, notably among those exposed as children, which persists into later life.

Reconstructing the abundance of Dounreay hot particles on an adjacent public beach in Northern Scotland.

Following the discovery of a number of hot particles in the offshore environment of Dounreay on the North Coast of Scotland in 1997, the Dounreay site operator was required to introduce rapid and extensive beach monitoring. Since the introduction of vehicular based beach monitoring in 1999 there have been two further generations of beach monitoring equipment, developed to satisfy regulatory requirements for particle detection and in response to the recommendations of the Dounreay Particles Advisory Group (DPAG). This paper reports the results of DPAG's review of beach monitoring capabilities, evaluating the factors influencing detection capability, assessing the likely monthly particle abundance and whether there has been any real change in particle arrivals with time.

Investigation of 18F-FDG 3D mode PET image quality versus acquisition time.

Objective: Three-dimensional (3D) mode positron emission tomography (PET) is being used increasingly for clinical PET imaging. However, as yet, optimal acquisition parameters have not been established. The aim of this study was to investigate the effect of varying acquisition time on 3D image quality using standard clinical activities of F-fluorodeoxyglucose (FDG).

Determination of left ventricular long-axis orientation using MRI: changes during the respiratory and cardiac cycles in normal and diseased subjects.

Background: It has previously been shown that magnetic resonance imaging (MRI) can be used to accurately determine left ventricular (LV) long-axis orientation in healthy individuals. However, the inter- and intra-observer variability in patients with acute coronary syndrome (ACS) and chronic heart failure (CHF) has not been explored. Furthermore, the changes in LV long-axis orientation because of respiration and during the cardiac cycle remain to be determined.

Investigation of the effect of subcutaneous fat on image quality performance of 2D conventional imaging and tissue harmonic imaging.

Tissue harmonic imaging (THI) has been reported to improve contrast resolution, tissue differentiation and overall image quality in clinical examinations. However, a study carried out previously by the authors (Brown et al. 2004) found improvements only in spatial resolution and not in contrast resolution or anechoic target detection.

Long-lived radiopharmaceuticals: dispensing from multidose vials.

We report the use of broth simulation as a means of validating the practice of sub-dispensing from stock vials of long-lived sterile radiopharmaceuticals. 'Matched' vials of nutrient broth accompanied the stock vials of long-lived sterile radiopharmaceuticals during their time in use and were subject to the same handling and storage procedures. At the end of the life of each radiopharmaceutical stock vial, the matching broth residue was sent for incubation and reporting.

Validation of a sensitivity performance index test protocol and evaluation of colour Doppler sensitivity for a range of ultrasound scanners.

The ability to detect flow is the most crucial aspect of an ultrasound (US) system because, if flow cannot be detected, no other aspect of performance matters. The objectives of this study were to validate a Doppler "sensitivity performance index," a figure of merit, and to determine if it could be used to differentiate colour Doppler sensitivity performance in scanners of varying complexity. The sensitivity performance index was developed to give a combined measure of related aspects of sensitivity, such as the lowest detectable velocity, the vessel size and the penetration depth.

Objective measurements of image quality.

Tissue harmonic imaging (THI) and compound imaging have been reported clinically to improve contrast resolution, tissue differentiation and overall image quality. However, there have been limited studies to date to quantify objectively the improvements in image quality achieved with these new imaging techniques. The aim of this study was to quantify differences in image quality that exist between conventional B-mode imaging, harmonic imaging, compound imaging and harmonic compound imaging.