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1.
Radiography (Lond) ; 28 Suppl 1: S93-S99, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36109264

RESUMO

OBJECTIVES: The COVID-19 pandemic caused an unprecedented health crisis resulting in over 6 million deaths worldwide, a figure, which continues to grow. In addition to the excess mortality, there are individuals who recovered from the acute stages, but suffered long-term changes in their health post COVID-19, commonly referred to as long COVID. It is estimated there are currently 1.8 million long COVID sufferers by May 2022 in the UK alone. The aim of this narrative literature review is to explore the signs, symptoms and diagnosis of long COVID and the potential impact on imaging services. KEY FINDINGS: Long COVID is estimated to occur in 9.5% of those with two doses of vaccination and 14.6% if those with a single dose or no vaccination. Long COVID is defined by ongoing symptoms lasting for 12 or more weeks post acute infection. Symptoms are associated with reductions in the quality of daily life and may involve multisystem manifestations or present as a single symptom. CONCLUSION: The full impact of long COVID on imaging services is yet to be realised, but there is likely to be significant increased demand for imaging, particularly in CT for the assessment of lung disease. Educators will need to include aspects related to long COVID pathophysiology and imaging presentations in curricula, underpinned by the rapidly evolving evidence base. IMPLICATIONS FOR PRACTICE: Symptoms relating to long COVID are likely to become a common reason for imaging, with a particular burden on Computed Tomography services. Planning, education and updating protocols in line with a rapidly emerging evidence base is going to be essential.


Assuntos
COVID-19 , COVID-19/complicações , COVID-19/diagnóstico por imagem , Humanos , Pandemias , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
2.
Radiography (Lond) ; 28(4): 1010-1015, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35926446

RESUMO

INTRODUCTION: The COVID-19 pandemic created major challenges across society, healthcare provision and also for those delivering healthcare education programmes. Clinical placements were disrupted and, in many incidences cancelled. Higher education institutions were required to move completely to online delivery methods with little notice. This created significant additional workload, stress and the need to learn new skills at a time of great uncertainty. This study explored the risks of burnout in academic radiographers during the first 12 months of the pandemic. METHODS: A survey was circulated using SurveyMonkey™ via personal, national and international networks, including the European Federation of Radiographer Societies (EFRS), to reach as many academic radiographers as possible. Disengagement and exhaustion were measured using the Oldenburg burnout inventory. Descriptive statistics and a one-way ANOVA were used to analyse the quantitative data using STATA V16 (Statacorp, TA). RESULTS: 533 academic radiographers responded to the survey from 43 different countries. Mean disengagement was in the medium range and exhaustion was high for the total dataset. In a subset of countries with 10 or more responses, there was significant variation between countries, with the UK having highest mean exhaustion score and the UK, Ireland and France sharing the highest mean disengagement score. In the total dataset, 86% agreed workload had increased during the pandemic and 35% had considered leaving academia in the last year. CONCLUSION: These data demonstrate the stark reality of the impact of the COVID-19 pandemic on academic radiographers' workload, wellbeing, and intention to leave their roles. IMPLICATIONS FOR PRACTICE: COVID-19 has had a significant impact on academic radiographers and this study highlights the urgent need for remedial measures to better support academic radiographers in order to ensure a sufficient, and sustainable workforce.


Assuntos
Esgotamento Profissional , COVID-19 , Pessoal Técnico de Saúde , Esgotamento Profissional/epidemiologia , COVID-19/epidemiologia , Humanos , Pandemias , Inquéritos e Questionários
3.
Radiography (Lond) ; 28 Suppl 1: S35-S40, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35927184

RESUMO

INTRODUCTION: The COVID-19 pandemic arrived in Europe in March 2020 and created major challenges across healthcare provision and for healthcare education programmes as well as having a major impact on society. Within the profession of Radiography changes in medical imaging, radiotherapy, and teaching practices have been reported along with the negative impact on radiographers and students. The aim of this study was to investigate key challenges relating to academic practice during the COIVD-19 pandemic; how radiography academics have coped and to identify recommendations for further support required to facilitate recovery of the academic faculty as the pandemic ebbs. METHODS: A survey was circulated using SurveyMonkey™ via personal, national and international networks, including the European Federation of Radiographer Societies (EFRS), to reach as many academic radiographers as possible. Open questions relating to the challenges of providing radiography education during the COVID-19 pandemic and the and coping strategies used were included. Thematic analysis was conducted using NVivo (QSR International, MA). RESULTS: 533 academic radiographers responded to the whole survey from 43 different countries, with 340 responses relating to challenges and 327 for coping strategies. The main themes for the challenges were clinical practice, communication with colleagues, lack of face to face, managing change, students (support), and staff support. The coping strategy themes were communication with colleagues, physical exercise, self-care and wellbeing. CONCLUSION: These data demonstrate a multitude of challenges for academic radiographers and the pressure they worked under during the first year of the COVID-19 pandemic was clear. However, the majority employed healthy coping strategies to help them deal with the pressure, uncertainty and trauma of the situation. IMPLICATIONS FOR PRACTICE: COVID-19 had a significant impact on academic radiographers and while many reported good strategies for coping, the level of pressure is unsustainable. This study highlights the need to support academic radiographers to ensure a sustainable workforce.


Assuntos
COVID-19 , Adaptação Psicológica , Pessoal Técnico de Saúde , COVID-19/epidemiologia , Humanos , Pandemias , Radiografia
4.
Radiography (Lond) ; 27 Suppl 1: S1-S2, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34518061
5.
Radiography (Lond) ; 27 Suppl 1: S58-S62, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34380589

RESUMO

OBJECTIVES: This paper will outline the status and basic principles of artificial intelligence (AI) in radiography along with some thoughts and suggestions on what the future might hold. While the authors are not always able to separate the current status from future developments in this field, given the speed of innovation in AI, every effort has been made to give a view to the present with projections to the future. KEY FINDINGS: AI is increasingly being integrated within radiography and radiographers will increasingly be working with AI based tools in the future. As new AI tools are developed it is essential that robust validation is undertaken in unseen data, supported by more prospective interdisciplinary research. A framework of stronger, more comprehensive approvals are recommended and the involvement of service users, including practitioners, patients and their carers in the design and implementation of AI tools is essential. Clearer accountability and medicolegal frameworks are required in cases of erroneous results from the use of AI-powered software and hardware. Clearer career pathways and role extension provision for healthcare practitioners, including radiographers, are required along with education in this field where AI will be central. CONCLUSION: With the current growth rate of AI tools it is expected that many of the applications in medical imaging will continue to develop to more accurate, less expensive and more readily available versions moving from the bench to the bedside. The hope is that, alongside efficiency and increased patient throughput, patient centred care and precision medicine will find their way in, so we will not only deliver a faster, safer, seamless clinical service but also one that will have the patients at its heart. IMPACT FOR PRACTICE: AI is already reaching clinical practice in many forms and its presence will continue to increase over the short and long-term future. Radiographers must learn to work with AI, embracing it and maximising the positive outcomes from this new technology.


Assuntos
Inteligência Artificial , Software , Previsões , Humanos , Estudos Prospectivos , Radiografia
6.
Radiography (Lond) ; 26(3): 198-204, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32052762

RESUMO

INTRODUCTION: Diagnostic student radiographer attrition is reported at 14%, 6% higher than the average for higher education, however, little research has been undertaken on this subject. This study explored risk factors for attrition and strategies that enabled these to be overcome. METHODS: A two-phase study was undertaken. Phase one: data for 579 former student diagnostic radiographers (468 completers and 111 non-completers) from 3 English universities were analysed. Logistic regression was used to estimate odds ratios and 95% confidence intervals for completion based on individual characteristics. Phase two: content analysis of data from an online survey of 186 current UK student diagnostic radiographers exploring their experiences was undertaken. RESULTS: Phase one: Attrition was 19%. Increased age, non A-level entry qualifications and poor academic performance were predictors of attrition (p < 0.005). Phase two: Challenges reported by groups identified as 'at risk' showed that for mature students and those with non-traditional entry qualifications, external responsibilities/pressures and financial pressures were likely to be the greatest cause of attrition and for younger students with traditional qualifications, academic difficulty and excessive workload were most significant. Scientific learning and academic writing were identified as the most common academic difficulties by all groups. Poor mental health may also be a risk factor. CONCLUSION: Although characteristics were identified that increased the chance of attrition, the study concluded that attrition is most likely to be multi-factorial. Academic and personal support were identified as key in students continuing their studies when they considered leaving. Clinical placement experience is likely to influence continuation decisions. IMPLICATIONS FOR PRACTICE: Transparency around course expectations and academic requirements together with ensuring high quality clinical placements may assist in reducing attrition.


Assuntos
Escolha da Profissão , Radiografia , Evasão Escolar/estatística & dados numéricos , Estudantes de Ciências da Saúde/estatística & dados numéricos , Tecnologia Radiológica/educação , Adolescente , Adulto , Feminino , Humanos , Masculino , Risco , Reino Unido , Adulto Jovem
7.
Radiography (Lond) ; 25(4): 359-364, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31582245

RESUMO

INTRODUCTION: We evaluated the reporting competency of radiographers providing preliminary clinical evaluations (PCE) for intraluminal pathology of computed tomography colonography (CTC). METHOD: Following validation of a suitable tool, audit was undertaken to compare radiographer PCE against radiology reports. A database was designed to capture radiographer and radiologist report data. The radiographer's PCE of intraluminal pathology was given a score, the "pathology discrepancy and significance" (PDS) score based on the pathology present, any discrepancy between the PCE and the final report, and the significance of that discrepancy on the management of the patient. Agreement was assessed using percentage agreement and Kappa coefficient. Significant discrepancies between findings were compared against endoscopy and pathology reports. RESULTS: There was agreement or insignificant discrepancy between the radiographer PCE and the radiology report for 1736 patients, representing 97.0% of cases. There was a significant discrepancy between findings in 2.8% of cases and a major discrepancy recorded for 0.2% of cases. There was a 98.4% agreement in the 229 cases where significant pathologies were present. CONCLUSION: From a database of 1815 studies acquired over three years and representing work done in a clinical environment, this study indicates a potential for trained radiographers to provide a PCE of intraluminal pathology.


Assuntos
Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada , Neoplasias Colorretais/diagnóstico por imagem , Competência Clínica , Colo/patologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Humanos , Radiografia/normas , Radiografia/estatística & dados numéricos , Estudos Retrospectivos
8.
Radiography (Lond) ; 24 Suppl 1: S28-S32, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30166005

RESUMO

INTRODUCTION: The Francis Report recommended an increased focus on compassion in healthcare, and recognition and non-judgmental acceptance of diversity is fundamental in compassionate patient care. The aim of this study was to achieve a wider understanding of diversity that includes individual patient needs, expectations, perceptions and feelings during diagnostic imaging. METHODS: Using thirty-four semi-structured interviews with individual patients, this qualitative study explored their experiences of undergoing diagnostic radiography examinations and asked what compassionate care meant to them and how it is perceived and manifested in the brief, task-focussed and highly technical diagnostic projection imaging encounter. Data were analysed using Thematic Analysis. RESULTS: Four key themes were identified from the analysis; these were: feelings and vulnerability; hidden emotions; professionalism and valued qualities and communication. CONCLUSION: Diversity is defined not only in terms of socio-cultural differences but also psychological ones, i.e. individual emotional and attitudinal characteristics, some of which may be consciously or unconsciously concealed. In order that patients are treated equitably and all of their care needs met, recommendations include a broader focus in education and training to include adapting communication skills and techniques in perception and expression of non-verbal cues. Further research into the pressures specific to the time-pressured, task-focussed, highly technical and rapid turnover environment of projection imaging radiography and how this impacts upon compassionate patient care would make a useful contribution to the field.


Assuntos
Competência Cultural/psicologia , Diversidade Cultural , Diagnóstico por Imagem , Empatia , Relações Profissional-Paciente , Populações Vulneráveis/psicologia , Comunicação , Emoções , Feminino , Humanos , Entrevistas como Assunto , Masculino
10.
Radiography (Lond) ; 24(2): 151-158, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29605113

RESUMO

INTRODUCTION: Disuse osteopenia is a known consequence of reduced weight-bearing and has been demonstrated at the hip following leg injury but has not been specifically studied in postmenopausal women. METHOD: Bilateral DXA (GE Lunar Prodigy) bone mineral density (BMD) measurements were taken at the neck of femur (NOF), total hip region (TH) and lumbar spine in postmenopausal female groups comprising controls (N = 43), new leg fractures (#<3wks) (N = 9), and participants who had sustained a leg fracture more than one year previously (#>1yr) (N = 24). #>1yr were assessed at a single visit and the remaining groups at intervals over twelve months. Weight-bearing, function, 3-day pedometer readings, and pain levels were also recorded. RESULTS: The #<3wks demonstrated significant (p < 0.05) losses in ipsilateral TH BMD at 6 weeks from baseline 0.927 ± 0.137 g/cm2, to 0.916 ± 0.151 g/cm2 improving to 0.946 ± 0.135 g/cm2 (n.s) at 12 months following gradual return to normal function and weight-bearing activity. The #>1yr scored significantly below controls in almost all key physical and functional outcomes demonstrating a long-term deficit in hip bone density on the ipsilateral side. CONCLUSION: The clinical significance of post-fracture reduction in hip BMD is a potential increased risk of hip fracture for a variable period that may be mitigated after return to normal function and weight-bearing. Improvement at 12 months in #<3wks is not consistent with #>1yr results indicating that long-term impairment in function and bone health may persist for some leg fracture patients. Unilateral bone loss could have implications for Fracture Liaison Services when assessing the requirement for medication post fracture.


Assuntos
Densidade Óssea , Doenças Ósseas Metabólicas/etiologia , Colo do Fêmur/diagnóstico por imagem , Fraturas do Quadril/etiologia , Fraturas por Osteoporose/complicações , Fraturas da Tíbia/complicações , Absorciometria de Fóton , Idoso , Estudos Transversais , Feminino , Quadril/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Pós-Menopausa , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Suporte de Carga
12.
Radiography (Lond) ; 23 Suppl 1: S48-S52, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28780951

RESUMO

INTRODUCTION: Academia is one area of practice in which radiographers can specialise; they compile approximately 2% of the total radiography profession in the UK, but are highly influential and essential for the education and development of the workforce in addition to undertaking research. However, the academic environment is very different to clinical practice and a period of transition is required. METHODS: Data were collated to explore the age and retirement profile of the academic radiography workforce in the UK; to understand the research time allocated to this workforce; the time required to develop a clinical radiographer into an academic and the mentorship and succession planning provisions nationally. An online UK wide survey was conducted and sent to all 24 Universities delivering radiography education within the UK. RESULTS: Eighteen out of 24 Universities in the UK responded to the survey. Approximately 30% of radiography academics are due to retire over the next 10 years, with over 25% of radiographers who currently hold a doctorate qualification included within this figure. Those entering academia have notably lower qualifications as a group than those who are due to retire. Developing clinical radiographers into academics was thought to take 1-3 years on average, or longer if they are required to undertake research. CONCLUSION: There is vulnerability in the academic radiography workforce. Higher education institutions need to invest in developing the academic workforce to maintain research and educational expertise, which is underpinned by master's and doctorate level qualifications.


Assuntos
Tecnologia Radiológica , Universidades , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aposentadoria/estatística & dados numéricos , Inquéritos e Questionários , Reino Unido , Recursos Humanos
13.
Leukemia ; 31(1): 151-158, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27363283

RESUMO

Genomic studies have identified recurrent somatic mutations in acute leukemias. However, current murine models do not sufficiently encompass the genomic complexity of human leukemias. To develop preclinical models, we transplanted 160 samples from patients with acute leukemia (acute myeloid leukemia, mixed lineage leukemia, B-cell acute lymphoblastic leukemia, T-cell ALL) into immunodeficient mice. Of these, 119 engrafted with expected immunophenotype. Targeted sequencing of 374 genes and 265 frequently rearranged RNAs detected recurrent and novel genetic lesions in 48 paired primary tumor (PT) and patient-derived xenotransplant (PDX) samples. Overall, the frequencies of 274 somatic variant alleles correlated between PT and PDX samples, although the data were highly variable for variant alleles present at 0-10%. Seventeen percent of variant alleles were detected in either PT or PDX samples only. Based on variant allele frequency changes, 24 PT-PDX pairs were classified as concordant while the other 24 pairs showed various degree of clonal discordance. There was no correlation of clonal concordance with clinical parameters of diseases. Significantly more bone marrow samples than peripheral blood samples engrafted discordantly. These data demonstrate the utility of developing PDX banks for modeling human leukemia, and emphasize the importance of genomic profiling of PDX and patient samples to ensure concordance before performing mechanistic or therapeutic studies.


Assuntos
Xenoenxertos/patologia , Leucemia/genética , Doença Aguda , Adolescente , Adulto , Animais , Células Sanguíneas/transplante , Transplante de Medula Óssea , Bovinos , Criança , Perfilação da Expressão Gênica , Humanos , Imunofenotipagem , Leucemia/patologia , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
14.
Biomed Res Int ; 2016: 3574258, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28025642

RESUMO

We aimed to study whether short-duration vibration exercise or football sessions of two different durations acutely changed plasma markers of bone turnover and muscle strain. Inactive premenopausal women (n = 56) were randomized to complete a single bout of short (FG15) or long duration (FG60) small sided football or low magnitude whole body vibration training (VIB). Procollagen type 1 amino-terminal propeptide (P1NP) was increased during exercise for FG15 (51.6 ± 23.0 to 56.5 ± 22.5 µg·L-1, mean ± SD, P < 0.05) and FG60 (42.6 ± 11.8 to 50.2 ± 12.8 µg·L-1, P < 0.05) but not for VIB (38.8 ± 15.1 to 36.6 ± 14.7 µg·L-1, P > 0.05). An increase in osteocalcin was observed 48 h after exercise (P < 0.05), which did not differ between exercise groups. C-terminal telopeptide of type 1 collagen was not affected by exercise. Blood lactate concentration increased during exercise for FG15 (0.6 ± 0.2 to 3.4 ± 1.2 mM) and FG60 (0.6 ± 0.2 to 3.3 ± 2.0 mM), but not for VIB (0.6 ± 0.2 to 0.8 ± 0.4 mM) (P < 0.05). Plasma creatine kinase increased by 55 ± 63% and 137 ± 119% 48 h after FG15 and FG60 (P < 0.05), but not after VIB (26 ± 54%, NS). In contrast to the minor elevation in osteocalcin in response to a single session of vibration exercise, both short and longer durations of small sided football acutely increased plasma P1NP, osteocalcin, and creatine kinase. This may contribute to favorable effects of chronic training on musculoskeletal health.


Assuntos
Creatina Quinase/sangue , Exercício Físico , Osteocalcina/sangue , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Futebol , Vibração , Adulto , Feminino , Humanos , Ácido Láctico/sangue , Pessoa de Meia-Idade , Fatores de Tempo
15.
Osteoporos Int ; 27(8): 2567-76, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26919995

RESUMO

UNLABELLED: Significant increased hip fracture incidence has been reported in the year following total knee replacement. This study demonstrates that bone and muscle loss is a post-surgical consequence of total knee replacement, alongside poor outcomes in function and activity potentially contributing to reduced quality of life and increased hip fracture risk. INTRODUCTION: A significant increase in hip fracture incidence in the year following total knee replacement (TKR) surgery has been reported. This study investigated function and activity following TKR and the effects of limited mobility on bone and muscle loss and their potential contribution to hip fracture risk. METHODS: Changes in dual-energy X-ray absorptiometry (DXA) (GE Lunar Prodigy, Bedford MA), bone mineral density (BMD) at the neck of femur (NOF), total hip region (TH) and lumbar spine were measured alongside leg lean tissue mass (LLTM) in post-menopausal Caucasian females following TKR (N = 19) compared to controls (N = 43). Lumbar spine trabecular bone scores (TBSs) were calculated. Ipsilateral/contralateral weight bearing, lower limb function, 3-day pedometer readings, pain levels and falls were also recorded. Measurements were obtained at pre-surgery baseline and at 6 weeks, 6 months and 12 months post-surgery. RESULTS: No statistically significant differences were demonstrated between groups at baseline bilaterally in LLTM or BMD at the NOF and TH. Losses in ipsilateral NOF and TH BMD and contralateral LLTM were significantly higher in the TKR group at 6 months. Impairment in function and weight bearing persisted in the TKR group 12 months post-operatively alongside deficits in bilateral muscle mass and ipsilateral NOF and TH BMD. Falls incidence was not significantly higher in the TKR group. CONCLUSIONS: Bone loss at the hip with associated muscle loss is a consequence of TKR that, in addition to poor patient outcomes in function and activity, potentially contributes to increased hip fracture risk in the year following surgery.


Assuntos
Artroplastia do Joelho , Densidade Óssea , Fraturas do Quadril/epidemiologia , Absorciometria de Fóton , Idoso , Feminino , Fêmur/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Pós-Menopausa , Qualidade de Vida , Fatores de Risco , População Branca
16.
Transpl Infect Dis ; 16(2): 213-24, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24589027

RESUMO

BACKGROUND: Invasive fungal infections are a major cause of morbidity and mortality among solid organ transplant (SOT) and hematopoietic cell transplant (HCT) recipients, but few data have been reported on the epidemiology of endemic fungal infections in these populations. METHODS: Fifteen institutions belonging to the Transplant-Associated Infection Surveillance Network prospectively enrolled SOT and HCT recipients with histoplasmosis, blastomycosis, or coccidioidomycosis occurring between March 2001 and March 2006. RESULTS: A total of 70 patients (64 SOT recipients and 6 HCT recipients) had infection with an endemic mycosis, including 52 with histoplasmosis, 9 with blastomycosis, and 9 with coccidioidomycosis. The 12-month cumulative incidence rate among SOT recipients for histoplasmosis was 0.102%. Occurrence of infection was bimodal; 28 (40%) infections occurred in the first 6 months post transplantation, and 24 (34%) occurred between 2 and 11 years post transplantation. Three patients were documented to have acquired infection from the donor organ. Seven SOT recipients with histoplasmosis and 3 with coccidioidomycosis died (16%); no HCT recipient died. CONCLUSIONS: This 5-year multicenter prospective surveillance study found that endemic mycoses occur uncommonly in SOT and HCT recipients, and that the period at risk extends for years after transplantation.


Assuntos
Blastomicose/epidemiologia , Coccidioidomicose/epidemiologia , Doenças Endêmicas , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Histoplasmose/epidemiologia , Transplante de Órgãos/efeitos adversos , Adolescente , Adulto , Idoso , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Blastomicose/tratamento farmacológico , Criança , Coccidioidomicose/tratamento farmacológico , Coinfecção/tratamento farmacológico , Coinfecção/epidemiologia , Comorbidade , Feminino , Histoplasmose/tratamento farmacológico , Humanos , Incidência , Itraconazol/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia , Fatores de Tempo , Estados Unidos/epidemiologia , Adulto Jovem
17.
Osteoarthritis Cartilage ; 15(6): 682-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17306566

RESUMO

OBJECTIVE: To determine regional differences in the orientation of collagen in the articular cartilage of the equine metacarpophalangeal joint as well as describing cartilage orientation in lesions using small angle X-ray scattering (SAXS). DESIGN: SAXS diffraction patterns were taken at the European Synchrotron Radiation Facility (ESRF), with increasing depth into cartilage and bone cross sections. Results for healthy samples were taken at different regions along the joint which receive different loads and differences in collagen orientation were determined. Results were also taken from diseased samples and the collagen orientation changes from that of healthy samples observed. RESULTS: Regions subject to low loads show a lower degree of orientation and regions exposed to the highest loads possess oriented collagen fibres especially in the radial layer. In early lesions the orientations of the collagen fibres are disrupted. Subchondral bone fibres are twisted in regions where the joint receives shear forces. Changes in fibre orientation are also observed in the calcified cartilage even in regions where the cartilage is intact. In more advanced lesions where there is loss of cartilage the fibres in the calcified layer are realigned tangential to the surface. CONCLUSIONS: Regional variations in collagen arrangement show that the highly ordered layers of the articular cartilage are the most important elements in supporting high variable loads. In lesions changes occur in the deep tissue whilst the overlying cartilage appeared normal. We therefore suggest that the interface region is a key element in the early stages of the disease.


Assuntos
Osso e Ossos/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Colágeno/análise , Cavalos/anatomia & histologia , Osteoartrite/diagnóstico por imagem , Difração de Raios X/métodos , Animais , Radiografia
18.
Calcif Tissue Int ; 78(1): 9-17, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16362461

RESUMO

The ability to assess a patient's risk of fracture is fundamental to the clinical role of bone densitometry. Fracture discrimination is quantified by the relative risk (RR), defined as the increased risk of fracture for a 1 standard deviation decrease in bone mineral density (BMD). The larger the value of RR, the more effective measurements are at identifying patients at risk of fracture. Epidemiological studies show that RR values for predicting the risk of any fracture are approximately the same for all BMD measurement sites. In this study, we show theoretically that this interesting observation is predictable and a consequence of two related observations: (1) that fracture prediction by BMD measurement sites distant from the fracture site is quantitatively explained by the correlation of BMD measurements and (2) that all correlation coefficients between distant BMD sites are comparable, with values in the range r = 0.55-0.65. The first of these conditions (referred to as the correlation hypothesis) is important because it sets a lower limit on the RR values at distant BMD sites on the assumption that measurements at these sites contain no independent information about fracture risk over and above that provided by their correlation with the fracture site BMD. If the correlation hypothesis is true, the present study points to the importance of the correlation coefficient between BMD sites as a key index that is indicative of the ability of different types of measurement to predict fracture risk. If, on the contrary, the correlation hypothesis is not valid, there is scope to improve bone densitometry by further studies to better identify those measurements that do provide independent information about fracture risk and how best to integrate this information with existing techniques to improve decision making.


Assuntos
Densidade Óssea , Osso e Ossos/lesões , Fraturas Espontâneas/diagnóstico , Modelos Estatísticos , Valor Preditivo dos Testes , Absorciometria de Fóton , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Suscetibilidade a Doenças , Fraturas Espontâneas/metabolismo , Humanos , Fatores de Risco
19.
Calcif Tissue Int ; 76(2): 113-20, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15645160

RESUMO

The DMS Lexxos is the first cone-beam dual X-ray absorptiometry (DXA) system capable of performing bone mineral density (BMD) measurements of the spine and hip. By using a two-dimensional (2-D) detector array rather than the linear array used with conventional fan-beam DXA systems, image acquisition time on Lexxos is only 1.5 s. However, the need to correct for the large signal from scattered radiation reaching the detector is a potential source of error in cone-beam DXA. The aim of this clinical evaluation of the Lexxos bone densitometer was to investigate the relative accuracy of cone-beam BMD measurements compared with conventional DXA by performing an in vivo cross-calibration study with an established fan-beam system, the Hologic QDR-4500. Spine (L1-L4) and hip BMD measurements were performed in 135 patients (111 women, 24 men) referred for a bone densitometry examination. Duplicate Lexxos measurements were performed in 27 female patients to evaluate precision. On average, Lexxos spine and femoral neck BMD measurements were 2% lower than those on the QDR-4500, whereas total hip BMD was 5% higher. Larger differences were found for the trochanter and Ward's triangle regions. For all sites, Lexxos BMD measurements showed a strong linear relationship with those measured on the QDR-4500 with correlation coefficients in the range r = 0.95 to 0.97 for the clinically important spine, femoral neck, and total hip regions. The root mean standard error (RMSE) between Lexxos and QDR-4500 BMDs ranged from 0.037 g/cm(2) for the femoral neck to 0.060 g/cm(2) for the spine, whereas Lexxos precision was 1.3% for total hip, 2.0% for femoral neck, and 2.3% for spine BMD. Although for the hip BMD sites the RMSE and precision of Lexxos measurements were similar to studies of pencil-beam and fan-beam DXA systems, the results for the spine were poorer than expected. The findings of this study suggest that Lexxos corrects accurately for the effects of scattered radiation at the detector, but that the precision of spine BMD measurements may be limited by involuntary patient movement between the high and low energy X-ray exposures.


Assuntos
Absorciometria de Fóton/instrumentação , Absorciometria de Fóton/métodos , Densidade Óssea , Articulação do Quadril/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Articulação do Quadril/metabolismo , Humanos , Vértebras Lombares/metabolismo , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
20.
Osteoporos Int ; 15(5): 367-74, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14685652

RESUMO

Osteoporosis is a highly prevalent but preventable disease and, as such, it is important that there are appropriate diagnostic criteria to identify those at risk of low trauma fracture. In 1994 the World Health Organization (WHO) introduced definitions of osteoporosis and osteopenia using T-scores, which identified 30% of all Caucasian post-menopausal women as having osteoporosis. However, the use of the WHO T-score thresholds of -2.5 for osteoporosis and -1.0 for osteopenia may be inappropriate at skeletal sites other than the spine, hip and forearm or when other modalities, such as quantitative ultrasound (QUS) are used. The aim of this study was to evaluate the age-dependence of T-scores for speed of sound (SOS) measurements at the radius, tibia, phalanx and metatarsal by use of the Sunlight Omnisense, to evaluate the prevalence of osteoporosis and osteopenia at these sites by use of the WHO criteria, and calculate appropriate equivalent T-score thresholds. The study population consisted of 278 healthy pre-menopausal women, 194 healthy post-menopausal women and 115 women with atraumatic vertebral fractures. All women had SOS measurements at the radius, tibia, phalanx and metatarsal and bone mineral density (BMD) measurements at the lumbar spine and hip. A group of healthy pre-menopausal women aged 20-40 years from the pre-menopausal group were used to estimate the population mean and SD for each of the SOS and BMD measurement sites. Healthy post-menopausal women were classified into normal, osteopenic or osteoporotic, based upon the standard WHO definition of osteoporosis and expressed as a percentage. We investigated the age-related decline in T-scores from 20-79 by stratifying the healthy subjects into 10-year age groups and calculating the mean T-score for each of these groups. Finally, we estimated appropriate T-score thresholds, using five different approaches. The prevalence of osteoporosis in the post-menopausal women aged 50 years and over ranged from 1.4 to 12.7% for SOS and 1.3 to 5.2% for BMD. The age-related decline in T-scores ranged from -0.92 to -1.80 for SOS measurements in the 60 to 69-year age group and -0.60 to -1.19 for BMD measurements in the same age group. The WHO definition was not suitable for use with SOS measurements, and revised T-score thresholds for the diagnosis of osteoporosis of -2.6, -3.0, -3.0 and -2.2 and for osteopenia of -1.4, -1.6, -2.3, and -1.4, for the radius, tibia, phalanx and metatarsal, respectively, were recommended.


Assuntos
Osteoporose Pós-Menopausa/diagnóstico por imagem , Adulto , Idoso , Envelhecimento/fisiologia , Densidade Óssea , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/fisiopatologia , Feminino , Dedos/diagnóstico por imagem , Humanos , Ossos do Metatarso/diagnóstico por imagem , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/fisiopatologia , Pós-Menopausa/fisiologia , Pré-Menopausa/fisiologia , Rádio (Anatomia)/diagnóstico por imagem , Valores de Referência , Fraturas da Coluna Vertebral/etiologia , Tíbia/diagnóstico por imagem , Ultrassonografia , Organização Mundial da Saúde
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