31 research outputs found
High-resolution 18F-FDG PET with MRI for monitoring response to treatment in rheumatoid arthritis
The characterization of breast anatomical metrics using dedicated breast CT
Purpose: Accurate anatomical characterization of the breast is useful in breast phantom development and computer modeling of breast imaging technologies. Capitalizing on the three-dimensional capabilities of dedicated breast CT (bCT), a number of parameters which describe breast shape and fibroglandular distribution are defined
Noise variance analysis using a flat panel x-ray detector: A method for additive noise assessment with application to breast CT applications
Purpose: A simplified linear model approach was proposed to accurately model the response of a flat panel detector used for breast CT (bCT)
The effect of skin thickness determined using breast CT on mammographic dosimetry
The effect of breast skin thickness on dosimetry in mammography was investigated. Breast computed tomography (CT) acquisition techniques, combined with algorithms designed for determining specific breast metrics, were useful for estimating skin thickness. A radial-geometry edge detection scheme was implemented on coronal reconstructed breast CT (bCT) images to measure the breast skin thickness. Skin thickness of bilateral bCT volume data from 49 women and unilateral bCT volume data from 2 women (10 healthy women and 41 women with BIRADS 4 and 5 diagnoses) was robustly measured with the edge detection scheme. The mean breast skin thickness (±inter-breast standard deviation) was found to be 1.45±0.30 mm. Since most current published normalized glandular dose (DgN) coefficients are based on the assumption of a 4-mm breast skin thickness, the DgN values computed with Monte Carlo techniques will increase up to 18% due to the thinner skin layers (e.g., 6-cm 50% glandular breast, 28 kVp Mo–Mo spectrum). The thinner skin dimensions found in this study suggest that the current DgN values used for mammographic dosimetry lead to a slight underestimate in glandular dose
Psychological, social and biological determinants of ill health (pSoBid): study protocol of a population-based study
Background: Disadvantaged communities suffer higher levels of physical and mental ill health than more advantaged communities. The purpose of the present study was to examine the psychosocial, behavioural and biological determinants of ill health within population groups in Glasgow that differed in socioeconomic status and in their propensity to develop chronic disease especially coronary heart disease and Type 2 diabetes mellitus.
Methods: Participants were selected at random from areas known to be at the extremes of the socioeconomic continuum in Glasgow. Within the categories of least deprived and most deprived, recruitment was stratified by sex and age to achieve an overall sample containing approximately equal numbers of males and females and an even distribution across the age categories 35–44, 45– 54 and 55–64 years. Individuals were invited by letter to attend for assessment of their medical history, risk factor status, cognitive function and psychological profile, morbidity, and carotid intima-media thickness and plaque count as indices of atherosclerosis. Anonymised data on study subjects were collected from the General Practice Administration System for Scotland to analyse
characteristics of participants and non-participants
Differences in atherosclerosis according to area level socioeconomic deprivation: cross sectional, population based study
Objectives To examine the relation between area level
social deprivation and ultrasound markers of
atherosclerosis (common carotid intima-media thickness
and plaque score), and to determine whether any
differences can be explained by “classic” (currently
recognised) or “emerging” (novel) cardiovascular risk
factors.
Design Cross sectional, population based study.
Setting NHS Greater Glasgow Health Board area.
Participants 666 participants were selected on the basis
of how their area ranked in the Scottish Index of Multiple
Deprivation 2004. Approximately equal numbers of
participants from the most deprived areas and the least
deprived areas were included, as well as equal numbers
of men and women and equal numbers of participants
from each age group studied (35-44, 45-54, and
55-64 years).
Main outcome measures Carotid intima-media thickness
and plaque score, as detected by ultrasound.
Results The mean age and sex adjusted intima-media
thickness was significantly higher in participants from the
most deprived areas than in those from the least deprived
areas (0.70 mm (standard deviation (SD) 0.16 mm) v
0.68mm(SD 0.12 mm); P=0.015). On subgroup analysis,
however, this difference was only apparent in the highest
age tertile in men (56.3-66.5 years). The difference in
unadjusted mean plaque score between participants
from the most deprived and those from the least deprived
areas was more striking than the difference in intimamedia
thickness (least deprived 1.0 (SD 1.5) v most
deprived 1.7 (SD 2.0); P<0.0001). In addition, a significant
difference in plaque score was apparent in the two
highest age tertiles in men (46.8-56.2 years and 56.3-66.
5 years; P=0.0073 and P<0.001) and the highest age
tertile in women (56.3-66.5 years; P<0.001). The
difference in intima-media thickness between most
deprived and least deprived males remained significant
after adjustment for classic risk factors, emerging risk
1.7 (SD 2.0); P<0.0001). In addition, a significant
difference in plaque score was apparent in the two
highest age tertiles in men (46.8-56.2 years and 56.3-66.
5 years; P=0.0073 and P<0.001) and the highest age
tertile in women (56.3-66.5 years; P<0.001). The
difference in intima-media thickness between most
deprived and least deprived males remained significant
after adjustment for classic risk factors, emerging risk
factors, and individual level markers of socioeconomic
status (P=0.010). Adjustment for classic risk factors and
emerging cardiovascular risk factors, either alone or in
combination, did not abolish the deprivation based
difference in plaque presence (as a binary measure;
adjusted odds ratio of 1.73, 95% confidence interval 1.07
to 2.82). However, adjustment for classic risk factors and
individual level markers of early life socioeconomic status
abolished the difference in plaque presence between the
most deprived and the least deprived individuals
(adjusted odds ratio 0.94, 95% CI 0.54 to 1.65; P=0.84).
Conclusions Deprivation is associated with increased
carotid plaque score and intima-media thickness. The
association of deprivation with atherosclerosis is
multifactorial and not adequately explained by classic or
emerging risk factors
Early life socioeconomic adversity is associated in adult life with chronic inflammation, carotid atherosclerosis, poorer lung function and decreased cognitive performance: a crosssectional, population-based study
Background: Socioeconomic gradients in health persist despite public health campaigns and improvements in healthcare. The Psychosocial and Biological Determinants of Ill-health (pSoBid) study was designed to uncover novel biomarkers of chronic disease that may help explain pathways between socioeconomic adversity and poorer physical and mental health.
Methods: We examined links between indicators of early life adversity, possible intermediary phenotypes, and markers of ill health in adult subjects (n = 666) recruited from affluent and deprived areas. Classical and novel risk factors for chronic disease (lung function and atherosclerosis) and for cognitive performance were assessed, and associations sought with early life variables including conditions in the parental home, family size and leg length.
Results: Associations were observed between father’s occupation, childhood home status (owner-occupier; overcrowding) and biomarkers of chronic inflammation and endothelial activation in adults (C reactive protein, interleukin 6, intercellular adhesion molecule; P < 0.0001) but not number of siblings and leg length. Lung function (forced expiratory volume in 1 second) and cognition (Choice Reaction Time, the Stroop test, Auditory Verbal Learning Test) were likewise related to early life conditions (P < 0.001). In multivariate models inclusion of inflammatory variables reduced the impact and independence of early life conditions on lung function and measures of cognitive ability. Including variables of adult socioeconomic status attenuated the early life
associations with disease biomarkers.
Conclusions: Adverse levels of biomarkers of ill health in adults appear to be influenced by father’s occupation and childhood home conditions. Chronic inflammation and endothelial activation may in part act as intermediary phenotypes in this complex relationship. Reducing the ‘health divide’ requires that these life course determinants
are taken into account