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1.
J Appl Clin Med Phys ; 25(2): e14256, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38175957

RESUMEN

In the context of radiation oncology, radiation exposure from radiation therapy simulation, image guidance, and radiation therapy procedures can have severe adverse biological effects on a developing embryo or fetus. Patients who may be pregnant are screened for the possibility of pregnancy to prevent unnecessary or excessive exposure of radiation in utero. Some radiation therapy patients for whom a pregnancy test is indicated may elect to decline the test. In addition, some patients who are found upon screening to be pregnant may decide, with their attending radiation oncologist, to continue with treatment. A radiation oncology department policy was developed to provide guidelines regarding screening and consent. The policy was designed to prevent unnecessary exposure to patients who may be pregnant, and to limit dose to the embryo or fetus in patients for whom treatment is medically indicated. The policy is presented as an example for physicists intending to develop or revise their own practice's policy regarding patients who may become pregnant.


Asunto(s)
Exposición a la Radiación , Oncología por Radiación , Embarazo , Femenino , Humanos , Feto/efectos de la radiación , Dosis de Radiación
2.
J Appl Clin Med Phys ; 25(8): e14394, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38887816

RESUMEN

PURPOSE: The treatment of brain tumors in pregnant patients poses challenges, as the out-of-field dose exposure to the fetus can potentially be harmful. A pregnant patient with prior radiation treatment was presented with a brain tumor at our clinic. This work reports on our pre-treatment study that compared fetal dose exposure between intensity-modulated proton therapy (IMPT) using pencil beam scanning (PBS) and conventional photon 3D conformal radiation therapy (3DCRT) and volumetric-modulated arc therapy (VMAT), and the subsequent pregnant patient's radiation treatment. MATERIALS AND METHODS: Pre-treatment measurements of clinical plans, 3DCRT, VMAT, and IMPT, were conducted on a phantom. Measurements were performed using a device capable of neutron detections, closely following AAPM guidelines, TG158. For photon measurements, fetus shielding was utilized. On patient treatment days, which was determined to be proton treatment, shielding was used only during daily imaging for patient setup. Additionally, an in vivo measurement was conducted on the patient. RESULTS: Measurements showed that IMPT delivered the lowest fetal dose, considering both photon and neutron out-of-field doses to the fetus, even when shielding was implemented for photon measurements. Additionally, the proton plans demonstrated superior treatment for the mother, a reirradiation case. CONCLUSION: The patient was treated with proton therapy, and the baby was subsequently delivered at full term with no complications. This case study supports previous clinical findings and advocates for the expanded use of proton therapy in this patient population.


Asunto(s)
Neoplasias Encefálicas , Feto , Órganos en Riesgo , Fantasmas de Imagen , Terapia de Protones , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Humanos , Embarazo , Femenino , Radioterapia de Intensidad Modulada/métodos , Neoplasias Encefálicas/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Terapia de Protones/métodos , Feto/efectos de la radiación , Órganos en Riesgo/efectos de la radiación , Radioterapia Conformacional/métodos , Adulto , Complicaciones Neoplásicas del Embarazo/radioterapia
3.
Int J Mol Sci ; 25(18)2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39337351

RESUMEN

Accidental exposure to high-dose radiation while pregnant has shown significant negative effects on the developing fetus. One fetal organ which has been studied is the placenta. The placenta performs all essential functions for fetal development, including nutrition, respiration, waste excretion, endocrine communication, and immunological functions. Improper placental development can lead to complications during pregnancy, as well as the occurrence of intrauterine growth-restricted (IUGR) offspring. IUGR is one of the leading indicators of fetal programming, classified as an improper uterine environment leading to the predisposition of diseases within the offspring. With numerous studies examining fetal programming, there remains a significant gap in understanding the placenta's role in irradiation-induced fetal programming. This review aims to synthesize current knowledge on how irradiation affects placental function to guide future research directions. This review provides a comprehensive overview of placental biology, including its development, structure, and function, and summarizes the placenta's role in fetal programming, with a focus on the impact of radiation on placental biology. Taken together, this review demonstrates that fetal radiation exposure causes placental degradation and immune function dysregulation. Given the placenta's crucial role in fetal development, understanding its impact on irradiation-induced IUGR is essential.


Asunto(s)
Desarrollo Fetal , Placenta , Exposición a la Radiación , Radiación Ionizante , Embarazo , Humanos , Femenino , Placenta/efectos de la radiación , Desarrollo Fetal/efectos de la radiación , Exposición a la Radiación/efectos adversos , Animales , Retardo del Crecimiento Fetal/etiología , Feto/efectos de la radiación
4.
Electromagn Biol Med ; 43(1-2): 71-80, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38366892

RESUMEN

To investigate curcumin (CUR) as the protector against the harmful effects of low-frequency electromagnetic field(LF- EMF, 50 Hz) during pregnancy period, 5 males and 15 females of Wistar rat mated and vaginal plaques were observed. Then, the pregnant rats were divided into six groups. During pregnancy(21 days), the EMF group was exposed to EMF for 30 min/day, the CUR group received a single dose of 50 mg/kg/daily CUR intraperitoneal, the EMF+CUR group was injected CUR and exposed to EMF daily. The DMSO(dimethyl sulfoxide) group was injected solvent of CUR (DMSO) intraperitoneal with the same volume of CUR solvent, the sham group was placed through the solenoid in the same conditions as the first group without exposure and the control group was kept in their cage in normal condition. After four weeks, babies born were divided according to the mother groups and sacrificed. Then, the three tissues injuries were investigated. EMF exposure led to an increase in outstanding necrotic areas in hippocampal tissue, an increase in the amount of hyperemia(p = 0.017) and necrotic(p = 0.005) in kidneys, and degeneration in liver tissue(p = 0.007) in the EMF group compared with EMF+CUR groups. A single dose of CUR daily during pregnancy can protect these tissues from injuries caused by LF-EMF exposure in rat fetuses.


Electromagnetic fields (EMFs) are able to penetrate and be absorbed by the body. The researchers showed that these radiations might be harmful and lead to cancers, cardiovascular diseases, mental disorders, and fetal abnormalities. Curcumin as an active component in turmeric has anti-inflammatory, antioxidant and anti-hyperlipidemia properties. It can protect the body against diseases such as arthritis, anxiety, and metabolic syndrome. This study examined the effects of curcumin as the protector against the harmful effects of EMF (50Hz) during pregnancy period. So the pregnant rats were divided into six groups. During pregnancy, a group was exposed to EMF for 30 min/day, the second group was injected a dose of curcumin 50mg/kg/daily, the third group was injected curcumin and exposed to EMF daily. The fourth group was injected a curcumin solvent dose, the sham group was placed through the field generator in the same conditions as the first group without exposure and the control group was kept in their cage in normal condition. After four weeks, babies born were divided according to the mother groups and sacrificed. Then, the liver, kidney, and hippocampal tissues were investigated. EMF exposure led to an outstanding increase in necrotic areas in hippocampal tissue, a notable increase in the amount of hyperemia and necrosis in kidneys, and degeneration in liver tissue(p=0.007) in the EMF group compared with the third group that was exposed to EMF and received curcumin. A single dose of curcumin daily during pregnancy can protect these tissues from injuries caused by EMF(50Hz) exposure in rat fetuses.


Asunto(s)
Curcumina , Campos Electromagnéticos , Feto , Ratas Wistar , Animales , Curcumina/farmacología , Embarazo , Femenino , Campos Electromagnéticos/efectos adversos , Ratas , Feto/efectos de la radiación , Feto/efectos de los fármacos , Masculino , Hipocampo/efectos de la radiación , Hipocampo/efectos de los fármacos , Hígado/efectos de la radiación , Hígado/efectos de los fármacos
5.
Mutagenesis ; 36(4): 303-309, 2021 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-34086940

RESUMEN

Radiation exposure in utero is known to lead to serious concerns to both the mother and children, including developmental anomalies in the children. In the recent past, trichostatin A, an HDAC (histone deacetylase) inhibitor and epigenetic modifier, has been shown to mitigate radiation-induced anomalies in the male reproductive system of C57BL/6 mice. Therefore, the current study was undertaken to evaluate the mitigating effects of trichostatin A (TSA) against radiation-induced developmental anomalies in mice. Foetuses of in utero whole-body gamma-irradiated mice during the active organogenesis period were examined for developmental anomalies at 8.5 and 18.5 days of gestation. In utero radiation exposure caused developmental anomalies like microcephaly, microphthalmia, gastroschisis and kinky tail besides prenatal mortality. TSA administration post-irradiation was observed to reduce 50% of prenatal mortality at E18.5 by reducing congenital and developmental anomalies. Observation of such results could be corroborated with the HDAC inhibitory potential of TSA knowing that developmental anomalies may have epigenetic origin. TSA, therefore, can be considered as a potential radiomitigator.


Asunto(s)
Feto/efectos de la radiación , Rayos gamma/efectos adversos , Ácidos Hidroxámicos/uso terapéutico , Teratogénesis , Animales , Epigénesis Genética , Femenino , Feto/efectos de los fármacos , Inhibidores de Histona Desacetilasas/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL
6.
Eur J Epidemiol ; 36(4): 415-428, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33492551

RESUMEN

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.


Asunto(s)
Supervivientes a la Bomba Atómica/estadística & datos numéricos , Feto/efectos de la radiación , Exposición Materna/efectos adversos , Mortalidad , Neoplasias Inducidas por Radiación/mortalidad , Exposición a la Radiación/estadística & datos numéricos , Adolescente , Adulto , Niño , Preescolar , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Femenino , Estudios de Seguimiento , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Embarazo/efectos de la radiación , Factores de Riesgo
7.
Radiat Environ Biophys ; 60(1): 93-113, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33591375

RESUMEN

This article presents nuclide-specific organ dose rate coefficients for environmental external exposures due to soil contamination assumed as a planar source at a depth of 0.5 g cm-2 in the soil and submersion to contaminated air, for a pregnant female and its fetus at the 24th week of gestation. Furthermore, air kerma free-in-air coefficient rates are listed. The coefficients relate the organ equivalent dose rates (Sv s-1) to the activity concentration of environmental sources, in Bq m-2 or Bq m-3, allowing to time-integrate over a particular exposure period. The environmental radiation fields were simulated with the Monte Carlo radiation transport codes PHITS and YURI. Monoenergetic organ dose rate coefficients were calculated employing the Monte Carlo code EGSnrc simulating the photon transport in the voxel phantom of a pregnant female and fetus. Photons of initial energies of 0.015-10 MeV were considered including bremsstrahlung. By folding the monoenergetic dose coefficients with the nuclide decay data, nuclide-specific organ doses were obtained. The results of this work can be employed for estimating the doses from external exposures to pregnant women and their fetus, until more precise data are available which include coefficients obtained for phantoms at different stages of pregnancy.


Asunto(s)
Feto/efectos de la radiación , Modelos Biológicos , Dosis de Radiación , Exposición a la Radiación , Adulto , Contaminantes Radiactivos del Aire , Femenino , Humanos , Método de Montecarlo , Fantasmas de Imagen , Fotones , Embarazo , Radioisótopos , Contaminantes Radiactivos del Suelo
8.
Radiographics ; 40(4): 1061-1070, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32559149

RESUMEN

CT scanning of a pregnant patient is often a source of distress for both patient and staff. Despite having expertise in image interpretation, a radiologist may not feel equipped to discuss the radiation-related safety issues during CT scanning of the fetus. In addition, patients are frequently concerned about the risk of adverse effects on the fetus from exposure to ionizing radiation. Recognizing the possibility of adverse effects from fetal exposure and the impossibility of direct in vivo measurement, medical physicists have developed several methods to estimate the amount of radiation reaching the fetus. A physician should know the potential biologic effects of fetal irradiation and at what radiation dose thresholds they occur. Physicians should also have an understanding of these methods and how the numbers they produce relate to potential fetal bioeffects. Furthermore, radiologists should have some understanding of how a qualified medical physicist calculates the fetal dose, how much they should trust those numbers, and the relevant variables that can affect the outcomes. Finally, the radiologist should know the magnitude of doses for CT scans commonly used in pregnant patients. Armed with this knowledge, a radiologist should be confident when discussing fetal dose and determining the best course of action for the pregnant patient. Online supplemental material is available for this article. ©RSNA, 2020.


Asunto(s)
Enfermedades Fetales/diagnóstico por imagen , Feto/efectos de la radiación , Radiometría , Tomografía Computarizada por Rayos X , Femenino , Humanos , Embarazo , Dosis de Radiación
9.
Bioelectromagnetics ; 41(8): 611-616, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33030760

RESUMEN

The widespread use of mobile phones and Wi-Fi-based communication devices makes exposure to radiofrequency electromagnetic fields (RF-EMF) unavoidable. Previous experiments have revealed the tumor-promoting effects of non-ionizing RF-EMF in adult carcinogen-treated mice in utero. To extend these investigations, we tested whether these effects are due to the co-carcinogenicity of RF-EMF which would manifest as elevated DNA damage. Similar to previous experiments, pregnant mice were exposed to RF-EMF (Universal Mobile Telecommunication System [UMTS] standard, approximately 1,960 MHz) from day 7 post-conception (p.c.) at 0 (sham), 0.04, and 0.4 W/kg SAR. At day 14 p.c., the mice were injected with the carcinogen ethylnitrosourea (ENU, 40 mg/kg). At three time-points specifically 24, 36, and 72 h later, the pregnant females were sacrificed and the fetuses (n = 24-57) were removed. A dye (cy3) specific for adenyl adducts was used to detect DNA damage by fluorescence microscopy in the brain, liver, and lung of each fetus. Compared to control (0 W/kg SAR), exposure to RF-EMF had no effect on the formation of DNA adducts in the inspected tissues. We conclude that increased adenyl formation of DNA by RF-EMF exposure is not a valid explanation for the previously reported tumor-promoting effects of RF-RMF. Our findings may help to gain a deeper insight into the biological effects of RF-EMF exposure in the context of malignancy. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.


Asunto(s)
Daño del ADN , Campos Electromagnéticos/efectos adversos , Etilnitrosourea/efectos adversos , Feto/metabolismo , Feto/efectos de la radiación , Ondas de Radio/efectos adversos , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/efectos de la radiación , Relación Dosis-Respuesta a Droga , Feto/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/efectos de la radiación , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/efectos de la radiación , Ratones
10.
Can Assoc Radiol J ; 71(3): 396-402, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32157904

RESUMEN

The use of diagnostic imaging studies in the emergency setting has increased dramatically over the past couple of decades. The emergency imaging of pregnant and lactating patients poses unique challenges and calls upon the crucial role of radiologists as consultants to the referring physician to guide appropriate use of imaging tests, minimize risk, ensure timely management, and occasionally alleviate unwarranted trepidation. A clear understanding of the risks and benefits involved with various imaging tests in this patient population is vital to achieve this. This review discusses the different safety and appropriateness issues that could arise with the use of ionizing radiation, iodinated-, and gadolinium-based contrast media and radiopharmaceuticals in pregnant and lactating patients. Special considerations such as trauma imaging, safety concerns with magnetic resonance imaging and ultrasound, management of claustrophobia, contrast extravasation, and allergic reactions are also reviewed. The consent process for these examinations has also been described.


Asunto(s)
Urgencias Médicas , Feto/efectos de la radiación , Lactancia/efectos de los fármacos , Complicaciones del Embarazo/diagnóstico por imagen , Exposición a la Radiación/prevención & control , Protección Radiológica/métodos , Heridas y Lesiones/diagnóstico por imagen , Medios de Contraste/efectos adversos , Femenino , Humanos , Trastornos Fóbicos/prevención & control , Embarazo , Radiofármacos/efectos adversos , Administración de la Seguridad
11.
J Radiol Prot ; 40(1): 280-295, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31770737

RESUMEN

In April 1986, the Chernobyl nuclear accident resulted in wide-scale contamination of Belarus with significantly elevated levels of radioiodine isotopes, mainly iodine-131 (131I), and long-lived radiocaesium isotopes, mainly caesium-137 (137Cs). Various groups of the population were affected by exposure to ionising radiation, including pregnant women and their foetuses. This paper describes the methods and results related to the establishment of a cohort of 2965 Belarusian people exposed in utero due to Chernobyl fallout. The cohort consists of individuals whose mothers resided in the most radioactively contaminated areas in Belarus at the time of the accident. Prenatal and postnatal doses to the thyroid due to intake of 131I, external irradiation and ingestion of radiocaesium isotopes were estimated for all cohort members. Ongoing research on this unique cohort will provide important information on adverse health effects following prenatal and postnatal exposure to radioiodine and radiocaesium isotopes, for which available epidemiological data are scant.


Asunto(s)
Accidente Nuclear de Chernóbil , Feto/efectos de la radiación , Mujeres Embarazadas , Ceniza Radiactiva , Adulto , Radioisótopos de Cesio , Exposición a Riesgos Ambientales , Femenino , Humanos , Radioisótopos de Yodo , Embarazo , Exposición a la Radiación , Radiación Ionizante , República de Belarús/epidemiología
12.
Neuroradiology ; 61(4): 443-449, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30770963

RESUMEN

PURPOSE: There is overwhelming evidence for the clinical benefits that are derived following mechanical thrombectomy in large-vessel acute ischaemic stroke. The risk of stroke is elevated in pregnancy due to many factors. To date, there have been two reports, totalling five patients, who have undergone mechanical thrombectomy in pregnancy, thus demonstrating the feasibility of the procedure; however, there is no data on the radiation exposure to the mother or foetus related to this therapy. METHODS: We highlight the important technical considerations to minimise the risk of the procedure and report the estimated dose received by mother and foetus. We also compare these doses with those received during whole-body CT in trauma and CT pulmonary angiogram (CTPA) examinations. RESULTS: Three cases of mechanical thrombectomy were performed at separate tertiary referral neuroscience centres in the UK. Following diagnostic CT and mechanical thrombectomy, the total whole-body effective dose to the pregnant patient was significantly higher than in patients undergoing CTPA (p < 0.05), but not significant different compared to whole-body CT imaging in trauma patients. The estimated dose received by the foetus following diagnostic CT and mechanical thrombectomy was significantly lower than in whole-body imaging in trauma patients at p < 0.05, with no difference in estimated foetal dose compared to CTPA imaging. CONCLUSION: The estimated doses received by the foetus during diagnostic stroke imaging and mechanical thrombectomy are equivalent to, or less than, purely diagnostic imaging in emergency situations.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Angiografía por Tomografía Computarizada/métodos , Feto/efectos de la radiación , Complicaciones Cardiovasculares del Embarazo/diagnóstico por imagen , Complicaciones Cardiovasculares del Embarazo/cirugía , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Adulto , Inglaterra , Femenino , Humanos , Embarazo , Dosis de Radiación , Imagen de Cuerpo Entero
13.
Nature ; 494(7436): 243-6, 2013 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-23334418

RESUMEN

Vascular patterning is critical for organ function. In the eye, there is simultaneous regression of embryonic hyaloid vasculature (important to clear the optical path) and formation of the retinal vasculature (important for the high metabolic demands of retinal neurons). These events occur postnatally in the mouse. Here we have identified a light-response pathway that regulates both processes. We show that when mice are mutated in the gene (Opn4) for the atypical opsin melanopsin, or are dark-reared from late gestation, the hyaloid vessels are persistent at 8 days post-partum and the retinal vasculature overgrows. We provide evidence that these vascular anomalies are explained by a light-response pathway that suppresses retinal neuron number, limits hypoxia and, as a consequence, holds local expression of vascular endothelial growth factor (VEGFA) in check. We also show that the light response for this pathway occurs in late gestation at about embryonic day 16 and requires the photopigment in the fetus and not the mother. Measurements show that visceral cavity photon flux is probably sufficient to activate melanopsin-expressing retinal ganglion cells in the mouse fetus. These data thus show that light--the stimulus for function of the mature eye--is also critical in preparing the eye for vision by regulating retinal neuron number and initiating a series of events that ultimately pattern the ocular blood vessels.


Asunto(s)
Ojo/irrigación sanguínea , Ojo/crecimiento & desarrollo , Feto/efectos de la radiación , Fototransducción/efectos de la radiación , Luz , Neuronas Retinianas/efectos de la radiación , Opsinas de Bastones/metabolismo , Animales , Recuento de Células , Hipoxia de la Célula/efectos de la radiación , Ojo/metabolismo , Ojo/efectos de la radiación , Femenino , Feto/citología , Feto/embriología , Feto/metabolismo , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica , Neovascularización Fisiológica/efectos de la radiación , Fotones , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/efectos de la radiación , Neuronas Retinianas/citología , Neuronas Retinianas/metabolismo , Opsinas de Bastones/deficiencia , Opsinas de Bastones/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
14.
Radiol Med ; 124(8): 736-744, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30949891

RESUMEN

The frequency of imaging examinations requiring radiation exposure in children (especially CT) is rapidly increasing. This paper reviews the current evidence in radiation protection in pediatric imaging, focusing on the recent knowledge of the biological risk related to low doses exposure. Even if there are no strictly defined limits for patient radiation exposure, it is recommended to try to keep doses as low as reasonably achievable (the ALARA principle). To achieve ALARA, several techniques to reduce the radiation dose in radiation-sensitive patients groups are reviewed. The most recent recommendations that provide guidance regarding imaging of pregnant women are also summarized, and the risk depending on dose and phase of pregnancy is reported. Finally, the risk-benefit analysis of each examination, and careful communication of this risk to the patient, is emphasized.


Asunto(s)
Dosis de Radiación , Exposición a la Radiación/prevención & control , Protección Radiológica/métodos , Tolerancia a Radiación , Radiación Ionizante , Niño , Preescolar , Daño del ADN/genética , Femenino , Feto/efectos de la radiación , Fluoroscopía/métodos , Gónadas/efectos de la radiación , Humanos , Neoplasias Inducidas por Radiación/prevención & control , Embarazo , Exposición a la Radiación/legislación & jurisprudencia , Traumatismos por Radiación/complicaciones , Traumatismos por Radiación/prevención & control , Protección Radiológica/legislación & jurisprudencia , Radiografía/efectos adversos , Valores de Referencia , Riesgo , Medición de Riesgo , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/normas
15.
Eur Radiol ; 28(3): 1054-1065, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28887589

RESUMEN

PURPOSE: This work provides detailed estimates of the foetal dose from diagnostic CT imaging of pregnant patients to enable the assessment of the diagnostic benefits considering the associated radiation risks. MATERIALS AND METHODS: To produce realistic biological and physical representations of pregnant patients and the embedded foetus, we developed a methodology for construction of patient-specific voxel-based computational phantoms based on existing standardised hybrid computational pregnant female phantoms. We estimated the maternal absorbed dose and foetal organ dose for 30 pregnant patients referred to the emergency unit of Geneva University Hospital for abdominal CT scans. RESULTS: The effective dose to the mother varied from 1.1 mSv to 2.0 mSv with an average of 1.6 mSv, while commercial dose-tracking software reported an average effective dose of 1.9 mSv (range 1.7-2.3 mSv). The foetal dose normalised to CTDIvol varies between 0.85 and 1.63 with an average of 1.17. CONCLUSION: The methodology for construction of personalised computational models can be exploited to estimate the patient-specific radiation dose from CT imaging procedures. Likewise, the dosimetric data can be used for assessment of the radiation risks to pregnant patients and the foetus from various CT scanning protocols, thus guiding the decision-making process. KEY POINTS: • In CT examinations, the absorbed dose is non-uniformly distributed within foetal organs. • This work reports, for the first time, estimates of foetal organ-level dose. • The foetal brain and skeleton doses present significant correlation with gestational age. • The conceptus dose normalised to CTDI vol varies between 0.85 and 1.63. • The developed methodology is adequate for patient-specific CT radiation dosimetry.


Asunto(s)
Feto/efectos de la radiación , Complicaciones del Embarazo/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Simulación por Computador , Femenino , Edad Gestacional , Humanos , Masculino , Método de Montecarlo , Fantasmas de Imagen , Embarazo , Dosis de Radiación , Radiografía Abdominal/métodos , Radiometría/métodos , Estudios Retrospectivos , Medición de Riesgo
16.
J Radiol Prot ; 38(3): 908-922, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29714717

RESUMEN

This study evaluates the impact of using non-reference fetal models on the fetal radiation dose from diagnostic radionuclide administration. The six-month pregnant phantoms including fetal models at the 10th and 90th growth percentiles were constructed at either end of the normal range around the 50th percentile and implemented in the Monte Carlo N-Particle code version MCNPX 2.6. This code has then been used to evaluate the 99mTc S factors of the target organs of interest, as this is the most commonly used radionuclide in nuclear medicine procedures. Substantial variations were observed in the S factors between the 10th/90th percentile phantoms from the 50th percentile phantom, with the greatest difference being 38.6%. When the source organs were in close proximity to, or inside the fetal body, the 99mTc S factors presented strong statistical correlations with fetal body habitus. The trends observed in the S factors and the differences between various percentiles were justified by the source organs' masses, and chord length distributions. The results of this study showed that fetal body habitus had a considerable effect on fetal dose (on average up to 8.4%) if constant fetal biokinetic data were considered for all fetal weight percentiles. However, a smaller variation on fetal dose (up to 5.3%) was obtained if the available biokinetic data for the reference fetus were scaled by fetal mass.


Asunto(s)
Feto/efectos de la radiación , Medicina Nuclear/métodos , Femenino , Humanos , Embarazo , Dosis de Radiación , Incertidumbre
17.
Eur J Epidemiol ; 32(12): 1075-1088, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28856527

RESUMEN

Iodine 131 (I-131), the principal component of nuclear fallout from the Chernobyl accident, concentrates in the thyroid gland and may pose risks to fetal development. To evaluate this, neonatal outcomes following the accident in April of 1986 were investigated in a cohort of 2582 in utero-exposed individuals from northern Ukraine for whom estimates of fetal thyroid I-131 dose were available. We carried out a retrospective review of cohort members' prenatal, delivery and newborn records. The relationships of dose with neonatal anthropometrics and gestational length were modeled via linear regression with adjustment for potentially confounding variables. We found similar, statistically significant dose-dependent reductions in both head circumference (-1.0 cm/Gy, P = 0.005) and chest circumference (-0.9 cm/Gy, P = 0.023), as well as a similar but non-significant reduction in neonatal length (-0.6 cm/Gy, P = 0.169). Gestational length was significantly increased with increasing fetal dose (0.5 wks/Gy, P = 0.007). There was no significant (P > 0.1) effect of fetal dose on birth weight. The observed associations of radioiodine exposure with decreased head and chest circumference are consistent with those observed in the Japanese in utero-exposed atomic bomb survivors.


Asunto(s)
Accidente Nuclear de Chernóbil , Feto/efectos de la radiación , Radioisótopos de Yodo/efectos adversos , Trimestres del Embarazo/efectos de la radiación , Efectos Tardíos de la Exposición Prenatal/epidemiología , Antropometría , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Retrospectivos , Ucrania/epidemiología
18.
J Appl Clin Med Phys ; 18(5): 330-335, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28799286

RESUMEN

This study aimed to examine the relationship between fetal dose and the dose-length product, and to evaluate the impact of the number of rotations on the fetal doses and maternal effective doses using a 320-row multidetector computed tomography unit in a wide-volume mode. The radiation doses for the pregnant woman and the fetus were estimated using ImPACT CT Patient Dosimetry Calculator software for scan lengths ranging from 176 to 352 mm, using a 320-row unit in a wide-volume mode and an 80-row unit in a helical scanning mode. In the 320-row unit, the fetal doses in all scan lengths ranged from 3.51 to 6.52 mGy; the maternal effective doses in all scan lengths ranged from 1.05 to 2.35 mSv. In the 80-row unit, the fetal doses in all scan lengths ranged from 2.50 to 3.30 mGy; the maternal effective doses in all scan lengths ranged from 0.83 to 1.68 mSv. The estimated conversion factors from the dose-length product (mGy・cm) to fetal doses (mGy) for the 320-row unit in wide-volume mode and the 80-row unit in helical scanning mode were 0.06 and 0.05 (cm-1 ) respectively. While using a 320-row MDCT unit in a wide-volume mode, operators must take into account the number of rotations, the beam width as automatically determined by the scanner, the placement of overlap between volumetric sections, and the ratio of overlapping volumetric sections.


Asunto(s)
Feto/efectos de la radiación , Fantasmas de Imagen , Dosis de Radiación , Exposición a la Radiación/análisis , Tomografía Computarizada por Rayos X , Femenino , Humanos , Tomografía Computarizada Multidetector , Embarazo , Radiometría
19.
Eur Radiol ; 26(4): 979-85, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26201294

RESUMEN

OBJECTIVE: To perform an internal audit at a university hospital with the aim of evaluating the number, clinical indication and operating procedure of computed tomography (CT) performed on pregnant patients and of estimating the radiation doses to the conceptus. METHODS: A retrospective review was conducted of all CT examinations performed in a single centre on pregnant patients between January 2008 and July 2013. The radiation doses to the conceptus were estimated. The results were compared with published data. RESULTS: The number of CT examinations during pregnancy increased from 3-4 per year in 2008-2011 to 11 per year in 2012. The mean estimated conceptus radiation dose was considered negligible for CT of the head and cervical spine, being less than 0.01 mGy, and for CT of the chest, less than 0.1 mGy. The estimated conceptus radiation dose from abdominopelvic CT was on average 28.7 mGy (range 6.7-60.5 mGy). CONCLUSIONS: The number of CT scans of pregnant patients increased threefold during the last few years. Most clinical indications and doses were in line with good clinical practice and literature; only in two cases the dose to the conceptus was higher than 50 mGy. KEY POINTS: • An increase in CT imaging of pregnant patients is of concern. • Clinical indications were in line with good practice. • Estimated conceptus doses were lower or similar to published data. • Internal guidelines for appropriate use of imaging during pregnancy should be established.


Asunto(s)
Feto/efectos de la radiación , Adulto , Vértebras Cervicales/efectos de la radiación , Femenino , Edad Gestacional , Humanos , Persona de Mediana Edad , Embarazo , Diagnóstico Prenatal/efectos adversos , Dosis de Radiación , Radiografía Torácica/efectos adversos , Estudios Retrospectivos , Tórax/efectos de la radiación , Tomografía Computarizada por Rayos X/efectos adversos , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
20.
J Vasc Interv Radiol ; 27(7): 1013-1020.e3, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27236211

RESUMEN

PURPOSE: To assess attitudes of interventional radiologists toward occupational ionizing radiation exposure in pregnancy and to survey practice patterns and outcomes. MATERIALS AND METHODS: A 34-question anonymous online survey on attitudes and work practices toward interventional radiologists who worked during pregnancy was sent to active SIR members, including 582 women. RESULTS: There were 534 (10%) respondents, including 142 women and 363 men. Among respondents, men were statistically older than women (P < .001) and had practiced interventional radiology (IR) longer (P < .001). Of female interventional radiologists, 55% had worked during pregnancy and reported no specific mutagenic events in their offspring. Spontaneous abortions (11%) and use of reproductive technology (17%) matched that of women with similar age and socioeconomic background. Although more women changed their work practice because of concerns of occupational exposure than men (23% vs 13%), this change was largely limited to the duration of a pregnancy. Among pregnant interventional radiologists, 4 (6%) completely abstained from performing fluoroscopically guided interventions (FGIs), whereas 31 (46%) continued to spend > 80% of their work week doing FGIs with additional protection. Perceptions of impact of pregnancy on daytime work redistribution varied significantly with gender (P < .001); however, perceptions regarding impact of pregnancy on on-call hours, distribution of complex cases, and need to hire for temporary coverage were similar between the genders. CONCLUSIONS: Most pregnant interventional radiologists continue to practice IR while pregnant. Pregnancy and fetal outcomes parallel that of the general population when matched for demographics. However, perceptions of impact of pregnancy on work lives of colleagues vary notably.


Asunto(s)
Exposición Profesional , Salud Laboral , Médicos Mujeres , Pautas de la Práctica en Medicina , Dosis de Radiación , Exposición a la Radiación , Radiografía Intervencional , Radiólogos , Salud de la Mujer , Mujeres Trabajadoras , Adulto , Anciano , Actitud del Personal de Salud , Femenino , Feto/efectos de la radiación , Conocimientos, Actitudes y Práctica en Salud , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Exposición Profesional/efectos adversos , Exposición Profesional/prevención & control , Embarazo , Complicaciones del Embarazo/etiología , Complicaciones del Embarazo/prevención & control , Exposición a la Radiación/efectos adversos , Exposición a la Radiación/prevención & control , Traumatismos por Radiación/etiología , Traumatismos por Radiación/prevención & control , Protección Radiológica , Radiografía Intervencional/efectos adversos , Medición de Riesgo , Factores de Riesgo , Adulto Joven
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