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1.
Br J Cancer ; 106(11): 1753-9, 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22531636

RESUMEN

BACKGROUND: The commencing age of cervical screening in England was raised from 20 to 25 years in 2004. Cervical cancer incidence in young women of England is increasing. It is not clear if this is due to either greater exposure to population risk factors or reduced cervical screening. METHODS: We measured if the relative risk of cervical cancer in younger women (20-29 years) of the north-east of England (NE) differed to that of women aged 30yrs and above since 2004. We also measured average annual percentage change (AAPC) in the 3 yr moving average incidence for all age-groups. Regional screening coverage rate and population risk factors were reviewed. Comparisons were made with Wales where screening continues to commence from the age of 20yrs. RESULTS: Cervical cancer incidence in women aged 20-29 increased annually by an average of 10.3% between 2000 and 2009. The rise in women aged 30-39 was less steep (3.5%/year) but no significant rise was observed in women aged 40-49. Socioeconomic factors remained stable or improved during the time period except for the incidence of chlamydia, herpes simplex and in particular, genital warts, which increased significantly in young women. Data from Wales show similar results. CONCLUSION: The incidence of cervical cancers in young women of the NE is increasing. The rise in incidence is unrelated to the change in screening policy in 2004. Close monitoring of incidence in young women and a greater attempt to reverse the current decline in screening coverage of women aged 25-29 years are recommended.


Asunto(s)
Neoplasias del Cuello Uterino/epidemiología , Adulto , Distribución por Edad , Detección Precoz del Cáncer/estadística & datos numéricos , Femenino , Humanos , Incidencia , Factores de Riesgo , Factores Socioeconómicos , Reino Unido/epidemiología , Gales/epidemiología , Adulto Joven
2.
BJOG ; 118(6): 685-92, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21429068

RESUMEN

OBJECTIVE: Recent meta-analyses have shown that loop treatment of the cervix of > 10 mm depth may be associated with adverse outcomes in future pregnancies. The aim of this study is to assess the rate of incomplete excision and recurrent disease in relation to depth of excision in women of reproductive age undergoing loop treatment. DESIGN: Observational cohort study. SETTING: Colposcopy Clinic, Northern Gynaecological Oncology Centre, Gateshead, UK. POPULATION: In all, 1558 women undergoing loop treatment for high-grade cervical intraepithelial neoplasia (HGCIN) between 1998 and 2003. METHODS: Women were followed up until 2008. Recurrence was analysed using Kaplan-Meier plots. OUTCOME MEASURES: Incomplete excision rates and recurrence rates. Recurrence was defined as post-treatment disease with high-grade histology. Any dyskaryotic cytology on follow-up was also documented. RESULTS: Recurrent high-grade disease on histology was found in 57/1558 (3.7%) women. In women ≤ 35 years old, despite a greater rate of incomplete excision at the endocervical margin at loop depths < 10 mm compared with ≥ 10 mm (24.4% versus 13.3%, P < 0.01), the recurrence rate was similar between the two groups (4.3% versus 3.4%, log-rank, P = 0.52). In contrast, a loop depth < 10 mm was associated with a higher disease recurrence rate (7.5% versus 3.0%, log-rank, P = 0.05) in women > 35 years. CONCLUSION: In women of reproductive age requiring treatment for HGCIN, colposcopists performing loop excision should aim for < 10 mm depth. This provides adequate treatment for HGCIN and minimises the potential risk of adverse outcomes in future pregnancies.


Asunto(s)
Recurrencia Local de Neoplasia , Complicaciones Neoplásicas del Embarazo/cirugía , Displasia del Cuello del Útero/cirugía , Neoplasias del Cuello Uterino/cirugía , Adulto , Femenino , Humanos , Estimación de Kaplan-Meier , Recurrencia Local de Neoplasia/patología , Embarazo , Complicaciones Neoplásicas del Embarazo/patología , Resultado del Embarazo , Resultado del Tratamiento , Neoplasias del Cuello Uterino/patología , Adulto Joven , Displasia del Cuello del Útero/patología
4.
Osteoporos Int ; 20(12): 2025-34, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19319617

RESUMEN

SUMMARY: Many falls occur among older adults with no traditional risk factors. We examined potential independent effects of lifestyle on fall risk. Not smoking and going outdoors frequently or infrequently were independently associated with more falls, indicating lifestyle-related behavioral and environmental risk factors are important causes of falls in older women. INTRODUCTION: Physical and lifestyle risk factors for falls and population attributable risks (PAR) were examined. METHODS: We conducted a 4-year prospective study of 8,378 community-dwelling women (mean age = 71 years, SD = 3) enrolled in the Study of Osteoporotic Fractures. Data on number of falls were self-reported every 4 months. Fall rates were calculated (# falls/woman-years). Poisson regression was used to estimate relative risks (RR). RESULTS: Physical risk factors (p < or = 0.05 for all) included tall height (RR = 0.89 per 5 in.), dizziness (RR = 1.16), fear of falling (RR = 1.20), self-reported health decline (RR = 1.19), difficulty with Instrumental Activities of Daily Living (IADLs) (RR = 1.12, per item), fast usual-paced walking speed (RR = 1.18, per 2 SD), and use of antidepressants (RR = 1.20), benzodiazepines (RR = 1.11), or anticonvulsants (RR = 1.62). Protective physical factors (p < or = 0.05 for all) included good visual acuity (RR = 0.87, per 2 SD) and good balance (RR = 0.85 vs. poor). Lifestyle predicted fewer falls including current smoking (RR = 0.76), going outdoors at least twice weekly but not more than once a day (RR = 0.89 and vs. twice daily). High physical activity was associated with more falls but only among IADL impaired women. Five potentially modifiable physical risk factors had PAR > or = 5%. CONCLUSIONS: Fall interventions addressing modifiable physical risk factors with PAR > or = 5% while considering environmental/behavioral risk factors are indicated.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Estilo de Vida , Accidentes por Caídas/prevención & control , Actividades Cotidianas , Distribución por Edad , Anciano , Antropometría/métodos , Mareo/complicaciones , Mareo/epidemiología , Femenino , Humanos , Actividad Motora , Estudios Prospectivos , Factores de Riesgo , Estados Unidos/epidemiología
5.
Inj Prev ; 15(5): 307-11, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19805598

RESUMEN

OBJECTIVE: To determine whether information on number of falls on a falls history screen predicts risk of non-vertebral and hip fracture. METHODS: A cohort of 5995 community-dwelling men aged 65 years and older (mean 73.7) was followed over 7.2 years for incident non-vertebral fractures. Cox proportional hazard models were used to calculate hazard ratios (HRs) (95% CI) for incident fracture comparing a history of one and two or more falls with no falls. Models were adjusted for age, clinic, body mass index, height, femoral neck bone mineral density and whether the participant had a non-trauma fracture after the age of 50. p

Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Fracturas Óseas/etiología , Anciano , Anciano de 80 o más Años , Densidad Ósea , Métodos Epidemiológicos , Cuello Femoral/fisiopatología , Fracturas Óseas/epidemiología , Fracturas Óseas/fisiopatología , Fracturas Espontáneas/epidemiología , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Fracturas de Cadera/fisiopatología , Humanos , Masculino , Anamnesis/métodos , Pronóstico , Estados Unidos/epidemiología
6.
Med Phys ; 35(2): 673-80, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18383689

RESUMEN

This article summarizes the dosimetric results of an International Atomic Energy Agency coordinated research program to investigate the feasibility of adopting guidance levels for invasive coronary artery procedures. The main study collected clinical data from hospitals located in five countries. A total of 2265 coronary angiograms (CA) and 1844 percutaneous coronary interventions (PCI) were analyzed. Substudies evaluated the dosimetric performance of 14 fluoroscopes, skin dose maps obtained using film, the quality of CA procedures, and the complexity of PCI procedures. Kerma-area product (PKA) guidance levels of 50 and 125 Gy cm2 are suggested for CA and PCI procedures. These levels should be adjusted for the complexity of the procedures performed in a given institution.


Asunto(s)
Guías de Práctica Clínica como Asunto , Protección Radiológica/métodos , Protección Radiológica/normas , Radiografía Intervencional/métodos , Radiografía Intervencional/normas , Radiometría/métodos , Radiometría/normas , Carga Corporal (Radioterapia) , Estudios de Factibilidad , Humanos , Proyectos Piloto , Dosis de Radiación , Efectividad Biológica Relativa
7.
Radiat Prot Dosimetry ; 129(1-3): 74-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18346966

RESUMEN

The contribution of interventional cardiology procedures to the population dose in Europe is poorly known. The estimation of the population dose from these procedures requires knowledge of both the typical dose received by patients and an estimate of the number of procedures undertaken annually. Data on the number of cardiology procedures in various European countries are available on the internet for a number of countries. However, this data set is incomplete or out of date. This paper describes the statistical analysis undertaken to estimate the number of interventional cardiology procedures in a number of European countries for 2007. Estimates of the number of procedures are given. On average, the number of cardiac catheterisations per million population is 5346, percutaneous transluminal coronary angioplasty is 1599 and 1214 stent procedures. In addition, there are an estimated 973 pacemaker insertions per million population.


Asunto(s)
Cardiología/métodos , Radiografía Intervencional/métodos , Radiografía Intervencional/estadística & datos numéricos , Angioplastia Coronaria con Balón/métodos , Cateterismo Cardíaco , Angiografía Coronaria/métodos , Europa (Continente) , Humanos , Stents
8.
Radiat Prot Dosimetry ; 131(1): 110-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18779185

RESUMEN

The past two decades have witnessed a technologically driven revolution in radiology. At the centre of these developments has been the use of computing. These developments have also been driven by the introduction of new detector and imaging devices in radiology and nuclear medicine, as well as the widespread application of computing techniques to enhance and extract information within the images acquired. Further advances have been introduced into digital practice. These technological developments, however, have not been matched by justification and optimisation studies to ensure that these new imaging devices and techniques are as effective as they might be, or performed at the lowest possible dose. The work programme of the SENTINEL Coordination Action was subdivided into eight work packages: functional performance and standards; efficacy and safety in digital radiology, dentistry and nuclear medicine, cardiology, interventional radiology, population screening/sensitive groups; justification, ethics and efficacy; good practice guidance and training; and project management. The intention of the work programme was to underwrite the safety, efficacy and ethical aspects of digital practice as well as to protect and add value to the equipment used in radiology.


Asunto(s)
Diagnóstico por Imagen/normas , Medicina Nuclear/normas , Radiología/normas , Cardiología/instrumentación , Cardiología/métodos , Odontología/métodos , Diagnóstico por Imagen/instrumentación , Diagnóstico por Imagen/métodos , Eficiencia , Unión Europea , Humanos , Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/métodos , Radiografía/instrumentación , Radiografía/métodos , Radiología/instrumentación , Radiología/legislación & jurisprudencia , Radiología/métodos , Seguridad
9.
Radiat Prot Dosimetry ; 129(1-3): 179-83, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18453556

RESUMEN

Justification and optimisation form the basic elements for the radiological protection of individuals for medical exposures. Justification includes the assessment of patient organ doses from which radiation risks are deduced. Medical radiation exposures are justified only in the case of a sufficient net benefit. For screening examinations, such as CT virtual colonoscopy, this implies that patient organ doses should be relatively low to minimise the radiation detriment. Image quality should be sufficient to maximise the potential diagnostic benefits. The Medical Exposures Directive places special attention on medical exposures as part of health screening programmes and examinations involving high individual doses to the patient, both of which apply to CT virtual colonoscopy. Technical factors were recorded for a series of patients having virtual colonoscopy on a CT scanner. In addition, the dose-length product was assessed. Patient organ doses were deduced using a CT dose calculation program. The typical effective dose was 7.5 mSv for male patients and 10.2 mSv for female patients. The effective dose is higher for female patients, as some gender-specific organs are irradiated during virtual colonoscopy. Each patient has two series of scans resulting in doses of 15 mSv for male patients and 20 mSv for female patients.


Asunto(s)
Colon/efectos de la radiación , Neoplasias del Colon/diagnóstico , Colonografía Tomográfica Computarizada/métodos , Tamizaje Masivo , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos , Tomografía Computarizada por Rayos X/métodos , Colonografía Tomográfica Computarizada/estadística & datos numéricos , Simulación por Computador , Femenino , Humanos , Masculino , Método de Montecarlo
10.
Radiat Prot Dosimetry ; 129(1-3): 328-32, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18319283

RESUMEN

The results of international calibration of Kerma Area Product (KAP) meters for European SENTINEL survey on patient dose optimisation of cardiac and interventional radiology practice are presented. Twelve countries were involved in the study. An investigation was conduced on 25 KAP meters fitted to undercouch X-ray tubes; 13 KAP meters were installed on cardiac units and the remaining 12 on interventional ones. The simplified calibration method has been applied, consisting of KAP estimation by multiplying the air kerma at the centre of the X-ray field by the irradiated area. The obtained values of calibration factors range from 0.4 to 0.9 and from 0.4 to 0.8 for KAP meters installed on cardiac and interventional units, respectively. They account also for table and mattress attenuation. For air kerma assessment, measurements with thermoluminescent dosemeters have been applied and when possible compared against an additional reference dosemeter. As the result of the investigation, the importance of calibration of KAP meters in clinical conditions that include mattress and table attenuation has been recognised.


Asunto(s)
Cardiología/instrumentación , Cardiología/normas , Exposición Profesional/análisis , Dosis de Radiación , Monitoreo de Radiación/métodos , Protección Radiológica/métodos , Radiología Intervencionista/instrumentación , Radiología Intervencionista/normas , Calibración , Cardiología/métodos , Recolección de Datos , Humanos , Radiología Intervencionista/métodos , Sensibilidad y Especificidad , Rayos X
11.
Radiat Prot Dosimetry ; 129(1-3): 184-90, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18483008

RESUMEN

In the United Kingdom National Health Service Breast Screening Programme (NHSBSP), women aged between 50 and 70 y are invited for mammography every 3 y. Screening histories for each woman, over four screening rounds, were analysed. Data from five screening programmes were used to select 57,425 women into the study. Cases were selected on the basis of being between the ages of 50 and 53 at the start of the NHSBSP (i.e. between 1989 and 1992). Assessment of the outcome for each screening round for each woman involved assigning a simple outcome code. Each of the possible pathways through the four screening rounds was analysed. This comprises of 500 possible pathways. This data enabled the following information to be determined: (i) The number of times a woman attended the screening programme. (ii) The number of women referred for assessment at each screening round. This information may be used to deduce the population dose to this group of women averaged over four screening rounds. Patient doses have been monitored since the programme's inception and are typically 4.5 mGy for two-view screening. It is possible to determine the mean glandular dose received by this cohort of women over four screening rounds by multiplying the number of examinations by the mean glandular dose for a typical woman. Allowance has to be made for the number of projections taken at each screening round. Once a woman has been screened, she may be invited back for further assessment if an abnormality is found on her mammogram. A stereotactic attachment is used to determine where to place the biopsy device. Although the dose received during a normal screening mammogram is well known, the dose for a stereotactic procedure and other assessment procedures is less well known, partly because only a small part of the breast is directly irradiated during stereotaxis. However, the woman may have multiple exposures during this stage. A prospective survey of doses was completed to deduce the mean glandular dose at the first assessment stage and during stereotaxis. Numbers of films, including magnification films taken at first-stage assessment were established in the North East of England and Scotland by means of a postal survey. Average total mean glandular dose was deduced using previous survey data for the screening programme and a multiplying factor to allow for magnification film dose. On average 1.6 full field and 0.15 collimated contact films are taken for each woman (with 2.25 and 0.75 mGy film(-1)), 1.0 full field and 0.9 collimated magnification views. The mean magnification film dose to the assessed breast was 5.0 and 1.7 mGy for a collimated magnification film. A survey of 134 women at screening centres in the North East of England was performed to deduce the mean glandular dose from digital stereotaxis which is almost universally used in breast screening. A typical woman received a dose to the assessed breast of 4.5 mGy with a range of 1.3-17 mGy. This data may be used to deduce the total mean glandular dose over four screening rounds including the assessment stages. The estimated mean glandular dose to a typical woman invited to the screening programme is approximately 16 mGy, when allowance for attendance rate and assessment rate over each screening round is made. The mean glandular dose to the population is approximately 4700 Sv y(-1).


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mamografía/métodos , Tamizaje Masivo/organización & administración , Programas Nacionales de Salud , Dosis de Radiación , Anciano , Neoplasias de la Mama/epidemiología , Inglaterra/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Medición de Riesgo
12.
Radiat Prot Dosimetry ; 129(1-3): 3-5, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18310611

RESUMEN

Health-care expenditure on radiological equipment in Europe is a growing fraction of the gross domestic product for all member states. This increase in expenditure has been driven by technical developments in equipment design, matched by the introduction of novel clinical practices, examinations and procedures. The radiation protection implications of these developments have to be assessed. The SENTINEL co-ordination action covered radiation protection, safety and related issues that arise from these technical and clinical developments. SENTINEL covered 90% of patient examinations in European Radiology, 60% of the collective dose from medical sources and approximately 50% of the collective dose to European citizens from man-made sources. The SENTINEL co-ordination actions 'main' objective was to address the safety and efficacy issues which are common to all digital diagnostic imaging systems, including nuclear medicine. High-dose procedures and sensitive groups (such as children) were covered by the project. Specifically, the co-ordination action aimed: (1) to establish both physical and clinical image quality criteria and link the two, (2) to undertake a series of dosimetry studies to establish the reference levels for new procedures and (3) to develop good practice guidelines for radiation protection in digital imaging and produce training material.


Asunto(s)
Diagnóstico por Imagen , Traumatismos por Radiación/prevención & control , Protección Radiológica/economía , Protección Radiológica/métodos , Radiometría/métodos , Humanos , Control de Calidad , Protección Radiológica/normas
13.
Radiat Prot Dosimetry ; 129(1-3): 199-203, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18430718

RESUMEN

For the dose study, a semi-automated method of data collection is used in this study. The participating centres were asked to fill out a spreadsheet with all necessary data and return it. For direct digital (DR) systems, the relevant data available in the DICOM header were used. All data is automatically added to a database and processed. The data were used to calculate the mean glandular dose for every image and for different thicknesses of polymethyl methacrylate phantoms using available conversion factors. Second-degree polynomials were fitted to the patient dose data and a reference dose curve was constructed for a range of thicknesses instead of a dose reference level at a single point. The dose reference curve rises from 1.57 mGy for a thickness of 30 mm to 2.50 mGy for 55 mm and 3.83 mGy for 75 mm. The results show centres that exceed this curve lie only in the lower or higher range of thicknesses and would remain undetected using a dose reference value in a single point. This gives better information to radiographers on where there is room for improvement of the dose levels in their system.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mama/efectos de la radiación , Recolección de Datos , Mamografía/estadística & datos numéricos , Mamografía/normas , Dosis de Radiación , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/prevención & control , Europa (Continente)/epidemiología , Femenino , Humanos , Mamografía/métodos , Valores de Referencia , Pantallas Intensificadoras de Rayos X
14.
Radiat Prot Dosimetry ; 129(1-3): 96-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18287190

RESUMEN

Relatively high organ doses absorbed by patients in interventional cardiology suggest the opportunity to define these patients as a cohort to be followed forward in time in an epidemiological study of the cancer risks associated with exposure to low-dose ionising radiation. In this paper, the UNSCEAR 2000 Report risk estimates for the most exposed organs/tissues in cardiac interventional procedures are reviewed, as well as the critical features of such an epidemiological study that is anticipated to have an intrinsically low statistical power because of the low levels of risk and possible confounding factors. To overcome these limitations, data collected in different institutions can be combined provided that a common design and conduct are used for dose assessment. A minimum dataset to be collected on a patient basis is proposed that can be implemented routinely in most facilities. This data should be linked to the local patient information system in order to retrieve all the exposures of a given patient.


Asunto(s)
Corazón/efectos de la radiación , Neoplasias Inducidas por Radiación/epidemiología , Dosis de Radiación , Radiología Intervencionista , Radioterapia/efectos adversos , Bases de Datos Factuales , Humanos , Radiación Ionizante , Medición de Riesgo
15.
Radiat Prot Dosimetry ; 129(1-3): 104-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18310612

RESUMEN

In interventional cardiology, a wide variation in patient dose for the same type of procedure has been recognised by different studies. Variation is almost due to procedure complexity, equipment performance, procedure protocol and operator skill. The SENTINEL consortium has performed a survey in nine european centres collecting information on near 2000 procedures, and a new set of reference levels (RLs) for coronary angiography and angioplasty and diagnostic electrophysiology has been assessed for air kerma-area product: 45, 85 and 35 Gy cm2, effective dose: 8, 15 and 6 mSv, cumulative dose at interventional reference point: 650 and 1500 mGy, fluoroscopy time: 6.5, 15.5 and 21 min and cine frames: 700 and 1000 images, respectively. Because equipment performance and set-up are the factors contributing to patient dose variability, entrance surface air kerma for fluoroscopy, 13 mGy min(-1), and image acquisition, 0.10 mGy per frame, have also been proposed in the set of RLs.


Asunto(s)
Diagnóstico por Imagen/normas , Dosis de Radiación , Traumatismos por Radiación/prevención & control , Monitoreo de Radiación/normas , Radiografía Intervencional/normas , Angioplastia Coronaria con Balón , Angiografía Coronaria , Electrofisiología , Fluoroscopía , Humanos , Valores de Referencia
16.
Radiat Prot Dosimetry ; 129(1-3): 204-10, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18310099

RESUMEN

Paediatric patients represent a very specific group within the radiology department. Compared to adult patients, they are more sensitive to radiation. As they are sometimes submitted to several radiology procedures, dose and image quality should be well balanced. Nowadays, only a few centres specialize in paediatric imaging, and knowledge of paediatric patient doses is, therefore, very scattered. The effect of the introduction of digital technology on paediatric patient doses remains largely undocumented. Data collected in the present survey illustrate that there is a clear need for standardisation in this domain. The proposal of a European diagnostic reference level (DRL) is quite difficult. Preliminary DRLs, based on typically 5-7 radiology centres per examination are proposed. The 'effective dose' may or may not be a very rigorous parameter, but it still remains useful nowadays to calculate a parameter that summarises the possible radiation-induced detriment to these young patients. However, conversion factors for calculation of the effective dose should be harmonised. Future studies should include an image quality evaluation study, using criteria that account for digital equipment. Data collection would be straightforward and could be performed in a systematic and automatic way if DICOM headers of digital images would include appropriate as well as relevant information for the particular case of paediatric examinations.


Asunto(s)
Abdomen/efectos de la radiación , Recolección de Datos , Pelvis/diagnóstico por imagen , Dosis de Radiación , Radiografía Torácica , Radiología/estadística & datos numéricos , Radiología/normas , Niño , Preescolar , Europa (Continente)/epidemiología , Humanos , Lactante , Recién Nacido , Radiología/métodos , Valores de Referencia
17.
Br J Radiol ; 79(942): 479-82, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16714749

RESUMEN

The balance between benefit and radiation risk in a breast cancer screening programme has received much attention at the initial screening stage. This paper extends that attention to first stage assessment, i.e. the first stage at which women are recalled for further investigation because of suspected lesions or other suspect film features, and prior to any biopsy. Numbers of films, including magnification films, taken at this stage, have been established in two UK regions by different methods. Average total mean glandular dose has been calculated using published data of dose per film from initial screening and a multiplying factor to allow for magnification film dose. It is concluded that the benefit/risk ratio is considerably higher at first stage assessment than at initial screening by a factor of between 4 and 9, because of the very much higher cancer detection rate in this well-defined sub-group of women. Qualitatively, this conclusion is unaffected by the quite wide variation between screening centres in the numbers of films taken at first stage assessment.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mamografía/efectos adversos , Tamizaje Masivo/efectos adversos , Anciano , Inglaterra , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Dosis de Radiación , Protección Radiológica , Medición de Riesgo
18.
Biochim Biophys Acta ; 1095(1): 78-82, 1991 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-1932129

RESUMEN

The serine proteinase inhibitor heparin cofactor II (HC) can be cleaved by polymorphonuclear leukocyte (PMN) elastase (LE) to yield potent chemotactic activity for PMN and monocytes. In contrast to the bacterially-derived chemotaxin formyl-Met-Leu-Phe (fMLP), the HC-derived chemotaxin does not stimulate PMN degranulation or oxidative burst activity. We compared the effects of HC-derived chemotaxins to the effects of fMLP on PMN actin conformation and on the cAMP levels. Both the HC chemotaxins and fMLP rapidly induced an increase in F-actin which was similar in magnitude and time-course. However, in contrast to fMLP, HC-derived chemotaxins did not elevate cAMP levels. HC-derived chemotaxins may be useful probes of chemotactic responses, since they do not have the mixed biological activities of fMLP.


Asunto(s)
Actinas/química , Factores Quimiotácticos/farmacología , Cofactor II de Heparina/metabolismo , Neutrófilos/química , Actinas/análisis , Quimiotaxis de Leucocito , Cofactor II de Heparina/farmacología , Humanos , Elastasa de Leucocito , Luz , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/efectos de los fármacos , Neutrófilos/fisiología , Elastasa Pancreática/metabolismo , Conformación Proteica/efectos de los fármacos , Dispersión de Radiación
19.
Radiat Prot Dosimetry ; 117(1-3): 195-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16461510

RESUMEN

Doses in radiology should be as low as reasonably achievable. In order to compare practice in different centres it is necessary to compare patient doses. This can only be undertaken if dosimetry studies are similar. In order to facilitate comparisons, the DIMOND consortium developed a patient dosimetry protocol. Reference doses have been proposed to identify centres where optimisation studies would be of benefit. Whilst reference doses have been established for common radiographic and fluoroscopic examinations, little research has been undertaken in the area of digital radiology, partly owing to the rapid technological changes occurring in digital and interventional radiology. Dosimetry data obtained by the DIMOND research project were compared with data from published literature. Data for various digital and interventional radiology procedures were reviewed. Proposals are made for reference doses. There is obviously a need for standardised approaches to patient dosimetry, which should be recorded in the hospital's information system.


Asunto(s)
Angiografía Coronaria/métodos , Protección Radiológica/métodos , Radiología/métodos , Radiometría/métodos , Angioplastia , Fluoroscopía/métodos , Humanos , Modelos Estadísticos , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos , Radiografía Intervencional/métodos , Estándares de Referencia
20.
Radiat Prot Dosimetry ; 117(1-3): 3-6, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16461511

RESUMEN

The DIMOND III project comprised work packages and subprojects to research digital imaging, interventional radiology and interventional cardiology, i.e. areas where there has been rapid technological change, not matched by radiation protection research. Whilst new practices have great potential benefit, there are risks to patients and staff if the technology is implemented inappropriately. DIMOND aimed to develop generic technology assessment and optimisation tools. Clinical quality criteria and technical parameters were included so that digital imaging procedures can be introduced appropriately. Frequency and dimensions of acceptance and constancy testing for digital imaging systems were studied, along with differences between objective measures of image quality and subjective indices. Patient dosimetry was performed to propose and to establish reference values. Clinical evaluation projects included cardiology, interventional radiology and digital mammography. As a result of the DIMOND project, quality criteria for several procedures were developed. Example results are presented in this paper.


Asunto(s)
Protección Radiológica/métodos , Radiometría/métodos , Cardiología/métodos , Humanos , Mamografía/métodos , Control de Calidad , Traumatismos por Radiación/prevención & control , Protección Radiológica/normas , Radiología Intervencionista/métodos
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