RESUMO
We examined the mortality risks among 2463 individuals who were exposed in utero to atomic bomb radiation in Hiroshima or Nagasaki in August 1945 and were followed from October 1950 through 2012. Individual estimates of mother's weighted absorbed uterine dose (DS02R1) were used. Poisson regression method was used to estimate the radiation-associated excess relative risk per Gy (ERR/Gy) and 95% confidence intervals (CI) for cause-specific mortality. Head size, birth weight, and parents' survival status were evaluated as potential mediators of radiation effect. There were 339 deaths (216 males and 123 females) including deaths from solid cancer (n = 137), lymphohematopoietic cancer (n = 8), noncancer disease (n = 134), external cause (n = 56), and unknown cause (n = 4). Among males, the unadjusted ERR/Gy (95% CI) was increased for noncancer disease mortality (1.22, 0.10-3.14), but not for solid cancer mortality (- 0.18, < - 0.77-0.95); the unadjusted ERR/Gy for external cause mortality was not statistically significant (0.28, < - 0.60-2.36). Among females, the unadjusted ERRs/Gy were increased for solid cancer (2.24, 0.44-5.58), noncancer (2.86, 0.56-7.64), and external cause mortality (2.57, 0.20-9.19). The ERRs/Gy adjusted for potential mediators did not change appreciably for solid cancer mortality, but decreased notably for noncancer mortality (0.39, < - 0.43-1.91 for males; 1.48, - 0.046-4.55 for females) and external cause mortality (0.10, < - 0.57-1.96 for males; 1.38, < - 0.46-5.95 for females). In conclusion, antenatal radiation exposure is a consistent risk factor for increased solid cancer mortality among females, but not among males. The effect of exposure to atomic bomb radiation on noncancer disease and external cause mortality among individuals exposed in utero was mediated through small head size, low birth weight, and parental loss.
Assuntos
Sobreviventes de Bombas Atômicas/estatística & dados numéricos , Feto/efeitos da radiação , Exposição Materna/efeitos adversos , Mortalidade , Neoplasias Induzidas por Radiação/mortalidade , Exposição à Radiação/estatística & dados numéricos , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Gravidez/efeitos da radiação , Fatores de RiscoRESUMO
AIM: Queensland has current radiation-protection guidelines; however, with the absence of data exploring compliance and implementation, the efficacy is unknown. The aim of the present study was to investigate the knowledge and attitudes on radiation protection among private North Queensland (NQ) dentists. METHODS: A quantitative methodology was employed in an observational and descriptive study using questionnaires for data collection. RESULTS: Of the 154 questionnaires distributed, 63 were completed and returned. The respondents' knowledge concerning the technical details of their equipment was limited, with 31.5% and 47% not knowing the tube voltage and current utilized for their machines, respectively. In total, 23.8% of dentists had limited knowledge about the speed of the conventional film they used, 90.5% of respondents agreed that the role of imaging in dentistry is important, and 75.8% dentists reported the thyroid as the most important organ to protect during dental radiography. Their knowledge regarding position-distance rule was reasonably adequate; 80.3% of the dental practices appeared to follow the Australian Radiation Protection and Nuclear Safety Agency guidelines, 95.2% preferred taking radiographs if it was only urgent, and 69.8% identified a need for spreading awareness regarding radiation protection. CONCLUSIONS: An opportunity and need for further continuing education was identified among NQ dentists to ensure safety of patients.
Assuntos
Atitude do Pessoal de Saúde , Odontólogos/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Proteção Radiológica/normas , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente/normas , Gravidez/efeitos da radiação , Queensland , Proteção Radiológica/métodos , Radiografia Dentária/efeitos adversos , Radiografia Dentária/normas , Radiologia/educação , Inquéritos e Questionários , Glândula Tireoide/efeitos da radiaçãoRESUMO
OBJECTIVES: Dental radiography may involve situations where the patient is known to be pregnant or the pregnancy is noticed after the X-ray procedure. In such cases, the radiation dose to the foetus, though low, needs to be estimated. Uniform and widely used guidance on dental X-ray procedures during pregnancy are presently lacking, the usefulness of lead shields is unclear and practices vary. METHODS: Upper estimates of radiation doses to the foetus and breasts of the pregnant patient were estimated with an anthropomorphic female phantom in intraoral, panoramic, cephalometric and CBCT dental modalities with and without lead shields. RESULTS: The upper estimates of foetal doses varied from 0.009 to 6.9 µGy, and doses at the breast level varied from 0.602 to 75.4 µGy. With lead shields, the foetal doses varied from 0.005 to 2.1 µGy, and breast doses varied from 0.002 to 10.4 µGy. CONCLUSIONS: The foetal dose levels without lead shielding were <1% of the annual dose limit of 1 mSv for a member of the public. Albeit the relative shielding effect, the exposure-induced increase in the risk of breast cancer death for the pregnant patient (based on the breast dose only) and the exposure-induced increase in the risk of childhood cancer death for the unborn child are minimal, and therefore, need for foetal and breast lead shielding was considered irrelevant. Most important is that pregnancy is never a reason to avoid or to postpone a clinically justified dental radiographic examination.
Assuntos
Mama/efeitos da radiação , Feto/efeitos da radiação , Doses de Radiação , Proteção Radiológica/instrumentação , Radiografia Dentária/métodos , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Humanos , Concentração Máxima Permitida , Imagens de Fantasmas , Gravidez/efeitos da radiação , Radiografia Interproximal/métodos , Radiografia Panorâmica/métodosRESUMO
Determinar la calidad del intercambio de flujo placentario que existe entre la madre y el feto es de suma importancia en situaciones que amenazan el bienestar materno-fetal, es por esto que la flujometría doppler fetal es una valiosa herramienta para prevenir daños posteriores por medio de la detección temprana y manejo oportuno de fetos con alteración del flujo placentario. La flujometría doppler es un método no invasivo que ha demostrado una mayor exactitud diagnóstica para la evaluación del bienestar fetal y una mayor sensibilidad y especificidad para diagnosticar la muerte perinatal y la baja calificación de APGAR al nacer. El presente trabajo de investigación consiste en un estudio descriptivo transversal que relacionó el resultado de la flujometría doppler fetal con los valores de APGAR a los 5 y 10 minutos en recién nacidos de embarazos mayores de 34 semanas, atendidos en el Hospital Materno Infantil 1º de Mayo en el año 2014. Los datos fueron recopilados por medio de la revisión de expedientes y procesados en la herramienta Epi InfoTM7 para su posterior interpretación. Se incluyó un total de 231 flujometrías, de las cuales se obtuvieron 209 con resultado normal y 22 alteradas, de estas últimas resultaron con APGAR debajo de 7 puntos un 40% a los 5 minutos y un 9% a los 10 minutos. En base a los resultados inferimos que la flujometría alterada tiene poco valor pronóstico de APGAR bajo al nacer, por lo que su indicación debe limitarse a embarazos con riesgo de insuficiencia placentaria, ya que realizarla de forma indiscriminada puede alterar las decisiones obstétricas e incrementar el intervencionismo médico en aquellos embarazos sin factores de riesgo
Assuntos
Gravidez/efeitos da radiação , Índice de Apgar , Fluxometria por Laser-Doppler , Ginecologia , ObstetríciaRESUMO
BACKGROUND: Exposure to electromagnetic fields (EMFs) and its effects at different frequencies on living beings has been investigated for decades. However, there are fewer studies that have been conducted on humans, thus this study aims to determine the effect of extremely low frequency (ELF) -EMFs on pregnancy, fetal growth and development in humans. MATERIAL: In this epidemiologic analytical cohort study, cases included pregnant women and their newborns. There were 222 women exposed to ELF-EMFs from high voltage electricity towers and cables during pregnancy and 158 women who had no exposure during pregnancy. Data that included pregnancy duration, neonatal birth weight, length, head circumference, gender and congenital malformations were collected through direct questions, measurements and referral to the registered data of related hospital or health center documents. Collected data was analyzed by SPSS-16. P < 0.05 was considered significant. RESULTS: No significant difference was found in pregnancy duration and preterm labor, neonatal birth weight, length, head circumference and congenital malformations in the two studied groups. CONCLUSION: Although the results of this study have shown no significant effects of ELF-EMFs on human pregnancy, fetal growth and development, taking precautionary measures to reduce exposure to EMFs by pregnant women seems logical. Conducting similar studies is strongly recommended.
Assuntos
Campos Eletromagnéticos/efeitos adversos , Desenvolvimento Fetal/efeitos da radiação , Gravidez/efeitos da radiação , Anormalidades Induzidas por Radiação/etiologia , Peso ao Nascer , Estudos de Coortes , Feminino , Humanos , Recém-NascidoRESUMO
We conducted a review of literature related to radiation effects on pregnant women, fetuses, and children from the perspective of epidemiology, pathology, and radiobiology. During 8-25 weeks post-conception the central nervous system is particularly sensitive to radiation. Fetal doses in excess of 100 mGy can result in some reduction of IQ (intelligence quotient). Fetal doses in the range of 1000 mGy can lead to severe mental retardation and microcephaly, particularly during 8-15 weeks and to a lesser extent 16-25 weeks after conception. Recent studies of cancers and chromosome aberrations indicated less radiosensitivity in prenatally exposed A-bomb survivors compared with postnatally exposed survivors, for which we provide possible hypotheses as an explanation.
Assuntos
Feto/efeitos da radiação , Gravidez/efeitos da radiação , Lesões por Radiação , Adolescente , Animais , Criança , Pré-Escolar , Feminino , Humanos , Doses de RadiaçãoRESUMO
Concerns regarding radiation exposure and its effects during pregnancy are often quoted as an important barrier preventing many women from pursuing a career in Interventional Cardiology. Finding the true risk of radiation exposure from performing cardiac catheterisation procedures can be challenging and guidelines for pregnancy exposure have been inadequate. The Women in Innovations group of Cardiologists with endorsement of the Society for Cardiovascular Angiography and Interventions aim to provide guidance in this publication by describing the risk of radiation exposure to pregnant physicians and cardiac catheterisation personnel, to educate on appropriate radiation monitoring and to encourage mechanisms to reduce radiation exposure. Current data do not suggest a significant increased risk to the fetus of pregnant women in the cardiac catheterisation laboratory and thus do not justify precluding pregnant physicians from performing procedures in the cardiac catheterisation laboratory. However, radiation exposure among pregnant physicians should be properly monitored and adequate radiation safety measures are still warranted.
Assuntos
Cardiologia , Feto/efeitos da radiação , Exposição Ocupacional , Gravidez/efeitos da radiação , Doses de Radiação , Radiologia Intervencionista , Anormalidades Induzidas por Radiação , Adulto , Feminino , Física Médica , Humanos , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/congênito , Proteção Radiológica , RadiometriaRESUMO
BACKGROUND: Diagnostic irradiation of the mother during pregnancy increases the risk of childhood acute lymphoblastic leukemia (ALL). There is inconsistent evidence on associations between ALL and other parental or childhood diagnostic irradiation. The aim of this analysis is to investigate whether diagnostic X-rays of the mother before birth, of the father before conception, or of the child increased the risk of childhood ALL. METHODS: Data from 389 cases and 876 frequency-matched controls were analyzed using unconditional logistic regression, adjusting for study matching factors and potential confounders. A meta-analysis of our findings in relation to paternal X-rays before conception with the published findings of previous studies was also conducted. RESULTS: There was no evidence of an increased risk with maternal abdominal X-rays before the birth of the index child or with the child having any X-rays more than 6 months before the censoring date. The odds ratio (OR) for any paternal abdominal X-ray before conception was 1.17 [95% confidence interval (95% CI), 0.88-1.55], and 1.47 (95% CI, 0.98-2.21) for more than one X-ray. The OR for any paternal intravenous pyelogram before conception was 3.56 (95% CI, 1.59-7.98). The pooled OR for this study with previous studies of any paternal abdominal X-rays before conception was 1.17 (95% CI, 0.92-1.48). CONCLUSIONS: There was some evidence of an increased risk of ALL in the offspring if the father had more than one abdominal X-ray before conception or had ever had an intravenous pyelogram. IMPACT: We plan to repeat this analysis by using pooled data to improve precision.
Assuntos
Exposição Materna/efeitos adversos , Exposição Paterna/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Gravidez/efeitos da radiação , Efeitos Tardios da Exposição Pré-Natal/etiologia , Radiografia/efeitos adversos , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Pai , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mães , Razão de Chances , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Fatores de Risco , Raios X/efeitos adversosRESUMO
The levels of liver lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamins A and E were used to follow the level of oxidative damage caused by ionizing radiation in pregnant rats. The possible protective effects of selenium and vitamin E supplemented to rats housed in concrete-protected cages using hematite and colemanite were tested and compared to untreated controls. Ninety-six rats were randomly divided into four main equal groups namely control (A), normal concrete (B), concrete containing colemanite (C), and concrete containing hematite (D). Except group A, all groups exposed to 7 Gy radiation. The four main groups were divided into four subgroups each as follows: subgroups 1 (n = 6): nonpregnant control rats. Subgroups 2 (n = 6): selenium and vitamin E combination was intraperitoneally (i.p.) given to the nonpregnant rats for 20 days. Subgroups 3 (n = 6): pregnant control rats. Subgroups 4 (n = 6): selenium and vitamin E combination was i.p. given to the pregnant rats for concessive 20 days. Lactate dehydrogenate, alkaline phosphates, and lipid peroxidation values were higher in subgroups 1 and 3 than in no radiation group although glutathione peroxidase and vitamin E levels in liver were lower in radiation group than in no radiation group. Lactate dehydrogenate activity and lipid peroxidation levels were found to be decreased in subgroups 2 and 4 protected with concrete containing hematite and colemanite when compared to subgroup 1 and 3 with normal concrete. The radiation doses in rats housed by concrete without colemanite and hematite exposed radiation clearly showed liver degeneration. In conclusion, selenium and vitamin E supplementations and housing by concrete with colemanite was found to offer protection against gamma-irradiation-induced liver damage and oxidative stress in rats, probably by exerting a protective effect against liver necrosis via its free radical scavenging and membrane stabilizing. Protective effects of colemanite in the liver seem to be more important than in hematite.
Assuntos
Boratos/uso terapêutico , Compostos Férricos/uso terapêutico , Fígado/efeitos da radiação , Gravidez/efeitos da radiação , Vitamina E/uso terapêutico , Animais , Feminino , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Fígado/efeitos dos fármacos , Minerais , Lesões Experimentais por Radiação/tratamento farmacológico , Radiação Ionizante , Protetores contra Radiação/uso terapêutico , Ratos , Ratos Wistar , Selênio/uso terapêuticoRESUMO
Neste trabalho descrevemos um sistema on-line, chamado Dose Fetal Web, que calcula a dose fetal e os riscos radiológicos devido a exposições clínicas ou ocupacionais de gestantes. O sistema utiliza a metodologia matemática onde são usados coeficientes de conversão de dose uterina para dose fetal, gerados por meio de simulações pelo método de Monte Carlo. Para exposição médica de uma paciente gestante, uma base de dados de informações de operação de equipamentos acompanhados por um programa de garantia de qualidade e parâmetros fetais e maternos coletados durante exames de ultrassonografia obstétrica são incorporados na estimativa da dose fetal. No caso de dose fetal de uma trabalhadora gestante sujeita à exposição ocupacional (IOE),informações de uma base de dados de monitoração pessoal como dose ocupacional e carga de trabalho são usadas nos cálculos. No primeiro caso, considerando-se uma paciente gestante de 26 semanas submetida a um procedimento abdominal AP (tensão aplicada ao tubo de 70 kVp e filtração total de 3 mmAl), a dose fetal calculada pelo sistema foi 4,61 mGy e os riscos radiológicos obtidos foram 5,0·10-4 e 0,14 para a probabilidade de indução de retardamento mental e declínio de pontos de QI, respectivamente. No segundo caso, considerando-se uma IOE gestante, e assumindo-se que ela utilize um avental de proteção de 0,5 mm de equivalência em chumbo durante cada procedimento de radiologia intervencionista, e que a leitura pessoal de um dosímetro TLD portado fora do avental foi de 2 mGy/mês, a dose fetal calculada pelo sistema foi 0,02 mSv/mês.
In this paper we describe an online software, named Dose Fetal Web, which calculates the dose of the fetus and the radiological risks from both medical and occupational exposures of pregnant women. The software uses a mathematical methodology where coefficients for converting uterus to fetal dose, NUD, have been calculated by using Monte Carlo simulation. In the fetal dose from diagnostic medical examination of the pregnant patient, database information regarding output and other equipment related parameters from the QA database, maternal and fetal parameters collected by ultrasound procedures were used for the fetal dose estimation. In the case of fetal dose of the pregnant staff member the database information regarding routine individual monitoring dosimetry, such as occupational dose and workload, were used for the estimation. In the first case, suppose a 26 weeks pregnant patient had to undergo a single AP Abdomen procedure (70 kVp peak tube voltage and total filtration 3 mmAl), the fetal dose calculated by the software was 4.61 mGy and the radiological risks would be 5.0·10-4 and 0.14 to the probability of mental retardation induction and decline in the IQ score, respectively. In the second case,considering that the staff member can be pregnant, and assuming that she wore a 0.5 mm lead equivalent apron during every interventional radiology procedure and a personal dosimetry reading of 2 mGyTLD/month measured with the TLDs outside the apron, the fetal dose calculated by the software was 0.02 mSv/month.
Assuntos
Humanos , Feminino , Gravidez , Dosagem Radioterapêutica/normas , Feto/efeitos da radiação , Gravidez/efeitos da radiação , Proteção Radiológica/instrumentação , Radioterapia Assistida por Computador/instrumentação , Radioterapia Assistida por Computador/normas , Radioterapia Assistida por Computador , Troca Materno-Fetal/efeitos da radiação , Calibragem/normas , Exposição Materna/efeitos adversos , Exposição Materna/prevenção & controle , Internet/tendências , Internet , Riscos Ocupacionais , Medida de Exposição à RadiaçãoRESUMO
UNLABELLED: AIM To estimate and evaluate the risks for the offspring due to the administration of radiopharmaceuticals to women during the first pregnancy weeks after conception (weeks p.c.). METHODS: The in-utero exposition of the embryo due to diagnostic nuclear medicine procedures, for which diagnostic reference levels (DRL) are specified, as well as due to radio iodine therapy (RIT) was determined. To this end, it is assumed that the activity of the diagnostic radiopharmaceuticals administered to the mother corresponds with the DRL and amounts to 600 MBq or 4 GBq 131I for RIT of benign or malignant thyroid disease, respectively. Based on these data, the radiation risk for the offspring was assessed and compared with the spontaneous risks (R0). RESULTS: The dose for the offspring does not exceed 7.8 mSv for the diagnostic procedures considered, resulting in an excess risk for the offspring of less than 0.12% (R0 approximately 25%) to die from cancer during life, of less than 0.07% (R0 approximately 0.2%) to develop cancer up to the age of 15 years, and of less than 0.16% (R0 approximately 2%) for hereditary effects. RIT during the first 8 weeks p.c. results in doses for the offspring of about 100-460 mSv, resulting in an excess risk for malformations of the child of 3.4%-22% (R0 approximately 6%). CONCLUSIONS: The risk of stochastic radiation effects for the offspring due to a diagnostic nuclear medicine procedure of the mother during the first 8 weeks p.c. is--compared with the spontaneous risks--very small; deterministic effects are unlikely. In contrast, deterministic effects for the offspring may occur following RIT. In order to decide on a possibly indicated abortion after RIT, an individual risk assessment is mandatory.
Assuntos
Gravidez/efeitos da radiação , Medição de Risco/métodos , Blastocisto/efeitos da radiação , Criança , Desenvolvimento Embrionário/efeitos da radiação , Feminino , Feto/efeitos da radiação , Humanos , Medicina Nuclear/estatística & dados numéricos , Organogênese/efeitos da radiação , Processos EstocásticosRESUMO
Over the past 50 years, our laboratory has provided consultations dealing with the risks of various environmental toxicant exposures during pregnancy. These contacts were primarily by telephone or written communications. Since the year 2000, the primary source of consultations has been via the internet. In 2007, the pregnancy website of the Health Physics Society received 1,299,672 visits. The contacts who downloaded information totaled 620,035. After reading the website information, 1442 individuals who were still concerned contacted me directly. Unfortunately, we have learned that many physicians and other counselors are not prepared to counsel patients concerning radiation risks. Approximately, 8% of the website contacts, who had consulted a professional, were provided inaccurate information that could have resulted in an unnecessary interruption of a wanted pregnancy. Research from our and other investigators' laboratories has provided radiation risk data that are the basis for properly counseling contacts with radiation exposures. Mammalian animal research has been an important source of information that improves the quality and accuracy of estimating the reproductive and developmental risks of ionizing radiation in humans. What are the reproductive and developmental risks of in utero ionizing radiation exposure? 1. Birth defects, mental retardation, and other neurobehavioral effects, growth retardation, and embryonic death are deterministic effects (threshold effects). This indicates that these effects have a no adverse effect level (NOAEL). Almost all diagnostic radiological procedures provide exposures that are below the NOAEL for these developmental effects. 2. For the embryo to be deleteriously affected by ionizing radiation when the mother is exposed to a diagnostic study, the embryo has to be exposed above the NOAEL to increase the risk of deterministic effects. This rarely happens when the pregnant women have x-ray studies of the head, neck, chest or extremities. 3. During the preimplantation and preorganogenesis stages of embryonic development, the embryo is least likely to be malformed by the effects of ionizing radiation because the cells of the very young embryo are omnipotential and can replace adjacent cells that have been deleteriously affected. This early period of development has been designated as "the all-or-none period." 4. Protraction and fractionation of exposures of ionizing radiation to the embryo decrease the magnitude of the deleterious effects of deterministic effects. 5. The increased risk of cancer following high exposures to ionizing radiation exposure to adult populations has been demonstrated in the atomic bomb survivor population. Radiation-induced carcinogenesis is assumed to be a stochastic effect (nonthreshold effect) so that there is theoretically a risk at low exposures. Whereas there is no question that high exposures of ionizing radiation can increase the risk of cancer, the magnitude of the risk of cancer from embryonic exposures following diagnostic radiological procedures is very controversial. Recent publications and analyses indicate that the risk is lower for the irradiated embryo than the irradiated child, which surprised many scientists interested in this subject, and that there may be no increased carcinogenic risk from diagnostic radiological studies. Examples of appropriate and inappropriate counseling will be presented to demonstrate how counseling can save lives and change family histories. The reader is referred to the Health Physics Society website to obtain many examples of the answers to questions posed by women and men who have been exposed to radiation (www.hps.org). Then click on ATE (ask the expert).
Assuntos
Aconselhamento , Feto/efeitos da radiação , Gravidez/efeitos da radiação , Lesões por Radiação/etiologia , Animais , Feminino , Humanos , Masculino , Gestantes , Diagnóstico Pré-Natal/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Lesões por Radiação/prevenção & controle , Radiação Ionizante , Radiografia/efeitos adversos , ReproduçãoRESUMO
The participation of pregnant women in radiology can be an emotional experience. The word "radiation" understandably invokes fear and uncertainty. Irradiation of a foetus should be avoided whenever possible. However, radiological examinations of pregnant women are often justified and unintended exposures do occur. Also pregnant radiology staff may remain working in the department. Lack of knowledge about the effects of both ionising (X-rays) and non-ionising (MRI) radiation is responsible for anxiety of patients and workers. If foetal exposures occur, they must be quantitatively evaluated and the risk put into perspective. This paper is intended to inform radiology managers, radiologists, technologists and referring clinicians in their management with pregnant patients and co-workers. The paper describes conceptus doses for both patient and worker that are associated with radiology practice, reviews the risks and effects of in utero irradiation, and discusses current national policies, international guidelines and practical aspects.
Assuntos
Diagnóstico por Imagem , Feto/efeitos da radiação , Exposição Materna/efeitos adversos , Gravidez/efeitos da radiação , Anormalidades Induzidas por Radiação/prevenção & controle , Relação Dose-Resposta à Radiação , Feminino , Humanos , Consentimento Livre e Esclarecido , Imageamento por Ressonância Magnética , Exposição Ocupacional/efeitos adversos , Doses de Radiação , Lesões por Radiação/prevenção & controle , Monitoramento de Radiação , Proteção RadiológicaRESUMO
A pesar de la creciente utilización de estudios radiológicos durante el embarazo, continúan existiendo percepciones erróneas respecto a posibles riesgos materno/fetales de su uso. En esta revisión presentamos la evidencia relevante sobre los efectos potenciales y la seguridad clínica de la exposición a radiación en estudios diagnósticos durante el embarazo. La mayoría de los exámenes exponen al feto a radiación en dosis menores a 50 mSv, las que han demostrado no ser dañinas. Los medios de contraste yodados pueden producir efectos deletéreos en la glándula tiroides del feto en desarrollo. Para el gadolinio existe limitada experiencia, por lo que no se recomienda su uso, a menos que el beneficio justifique los riesgos potenciales. Tanto la ultrasonografía como la resonancia magnética son seguros para el feto, por lo que debieran ser preferidos. Recomendamos descartar embarazo antes de efectuar un estudio de radiodiagnóstico a una mujer en edad fértil, con el objetivo de no exponer a los fetos a radiación ionizante de manera no justificada. Sin embargo, cuando la necesidad diagnóstica y el tratamiento asociado lo requieran, el examen debe ser solicitado de manera usual informando a los pacientes los potenciales riesgos y beneficios.
Despite the increasing use of radiologic test during pregnancy, there are still wrong perceptions about maternal and fetal risks. Here we present relevant evidence about safety and potential side effects of radiation exposure in diagnostic imaging during pregnancy. Most x-ray studies expose the fetus to doses lower than 50 mSv, that have proven to be harmless. Iodine-based contrast media may damage the developing fetuses' thyroid gland. Experience in gadolinium use is limited, thus its use is not recommended, unless the potential benefit worth its potential risk. Both ultrasound and magnetic resonance are safe to the fetus and they should be preferred over other techniques. We recommend discarding pregnancy before proceeding with any radio-diagnostic study in women of reproductive age, in order to prevent unnecessary fetal exposure to ionizing radiation. Nevertheless, when clinically justified, the x-ray study must be performed as usual, informing the patients about the potential risks and benefits.
Assuntos
Humanos , Feminino , Gravidez , Radiação Ionizante , Gravidez/efeitos da radiaçãoRESUMO
Many pregnant women are exposed to radiation either as a patient or as an employee. Ignorance of the issues surrounding the radiation exposure of pregnant females is encountered among medical and other professionals, often leading to undue concern. The exposure of pregnant patients has to be justified and the risk/benefit carefully assessed. Diagnostic radiological and nuclear medicine procedures do not usually pose an increased risk to the fetus but therapeutic procedures and radiotherapy may do so. Risks are greatest during organogenesis and the first trimester. Informed consent and counseling of the patient are important. Pregnant females working with radiation also need separate consideration and careful monitoring. The author has personal experience of this working as an interventional radiologist throughout pregnancy. Education of professionals working with radiation and in medicine is essential and international organizations in radiation protection should continue to provide and support this role.
Assuntos
Gravidez/efeitos da radiação , Proteção Radiológica/métodos , Anormalidades Induzidas por Radiação/etiologia , Anormalidades Induzidas por Radiação/prevenção & controle , Exposição Ambiental , Feminino , Feto/efeitos da radiação , Idade Gestacional , Humanos , Radiação , Doses de Radiação , Risco , Medição de Risco/métodosRESUMO
El uso de exámenes de imágenes para el diagnóstico de condiciones no obstétricas puede ser requerido durante cualquier etapa del embarazo. Existe un riesgo teórico de defectos en el desarrollo fetal, el que se ha considerado no relevante con el nivel de dosis aportada por la radiología diagnóstica habitual. La comprensión de los efectos de la radiación en las diferentes etapas del desarrollo fetal y las dosis aportadas por las diferentes técnicas de imágenes debieran colaborar en la elección del tipo de examen a realizar y del mejor momento para hacerlo.
Diagnostic imaging studies can be required during any phase of the pregnancy for the diagnosis of not obstetric conditions. A theoretical risk of defects in the fetal development exists, but it has been considered insignificant at the dose level used for regular radiology practice. Comprehension of radiation effects over fetal development at different pregnancy stages and the relation between imaging modality and dose can help to make a choice, selecting the best radiologic examination and the best moment to do it.
Assuntos
Humanos , Feminino , Gravidez , Gravidez/efeitos da radiação , Feto/efeitos da radiação , Radiografia/efeitos adversos , Risco , Raios X/efeitos adversos , Tomografia Computadorizada por Raios X/efeitos adversos , Útero/efeitos da radiaçãoRESUMO
BACKGROUND: For women with differentiated thyroid carcinoma (DTC), the effect of radioactive iodine (RAI) therapy on gonadal and reproductive function is an important consideration. OBJECTIVE AND METHODS: We systematically reviewed controlled studies examining the gonadal and reproductive effects of RAI therapy in women and adolescents surviving DTC. We searched nine electronic databases. All abstracts and papers were independently reviewed by two reviewers. RESULTS: After reviewing 349 unique citations and 61 full-text papers, 16 papers including data from 3023 women or adolescents with DTC were included. All studies were observational, with no long-term randomized control trial data. The age at first RAI treatment varied from 8 to 50 years and the cumulative activities of RAI administered for treatment varied from 30 to 1099 mCi. Transient absence of menstrual periods occurred in 8-27% of women within the first year after RAI, particularly in older women. In addition, RAI-treated women experienced menopause at a slightly younger age than women not treated with RAI. In the first year after RAI therapy, several studies reported increased rates of spontaneous and induced abortions. However, RAI treatment for DTC was generally not associated with a significantly increased risk of long-term infertility, miscarriage, induced abortions, stillbirths, or offspring neonatal mortality or congenital defects. CONCLUSIONS: In female survivors of DTC, there is little observational evidence to suggest important adverse effects of RAI treatment on gonadal function, fertility or pregnancy outcomes beyond 12 months, with the exception of a possible slightly earlier age of menopause.
Assuntos
Carcinoma/radioterapia , Radioisótopos do Iodo/uso terapêutico , Ovário/efeitos da radiação , Gravidez/efeitos da radiação , Sobreviventes , Neoplasias da Glândula Tireoide/radioterapia , Algoritmos , Carcinoma/fisiopatologia , Carcinoma/reabilitação , Feminino , Humanos , Radioisótopos do Iodo/efeitos adversos , Radioisótopos do Iodo/farmacologia , Ovário/fisiologia , Neoplasias da Glândula Tireoide/fisiopatologia , Neoplasias da Glândula Tireoide/reabilitaçãoRESUMO
This paper presents a systematic procedure to evaluate the induced current densities and electric fields due to walk-through metal detector (WTMD) exposure. This procedure is then used to assess the exposure of nine pregnant women models exposed to one WTMD model. First, we measured the magnetic field generated by the WTMD, then we extracted the equivalent current source to represent the WTMD emissions and finally we calculated the induced current densities and electric fields using the impedance method. The WTMD emissions and the induced fields in the pregnant women and fetus models are then compared to the ICNIRP Guidelines and the IEEE C95.6 exposure safety standard. The results prove the consistency between maximum permissible exposure (MPE) levels and basic restrictions for the ICNIRP Guidelines and IEEE C95.6. We also found that this particular WTMD complies with the ICNIRP basic restrictions for month 1-5 models, but leads to both fetus and pregnant women overexposure for month 6-9 models. The IEEE C95.6 restrictions (MPEs and basic restrictions) are not exceeded. The fetus overexposure of this particular WTMD calls for carefully conducted safety evaluations of security systems before they are deployed.