Determining and Managing Fetal Radiation Dose from Diagnostic Radiology Procedures in Turkey

OBJECTIVE: We intended to calculate approximate fetal doses in pregnant women who underwent diagnostic radiology procedures and to evaluate the safety of their pregnancies. MATERIALS AND METHODS: We contacted hospitals in different cities in Turkey where requests for fetal dose calculation are usually sent. Fetal radiation exposure was calculated for 304 cases in 218 pregnant women with gestational ages ranging from 5 days to 19 weeks, 2 days. FetDose software (ver. 4.0) was used in fetal dose calculations for radiographic and computed tomography (CT) procedures. The body was divided into three zones according to distance from the fetus. The first zone consisted of the head area, the lower extremities below the knee, and the upper extremities; the second consisted of the cervicothoracic region and upper thighs; and the third consisted of the abdominopelvic area. Fetal doses from radiologic procedures between zones were compared using the Kruskal-Wallis test and a Bonferroni-corrected Mann-Whitney U-test. RESULTS: The average fetal doses from radiography and CT in the first zone were 0.05 ± 0.01 mGy and 0.81 ± 0.04 mGy, respectively; 0.21 ± 0.05 mGy and 1.77 ± 0.22 mGy, respectively, in the second zone; and 6.42 ± 0.82 mGy and 22.94 ± 1.28 mGy, respectively, in the third zone (p < 0.001). Our results showed that fetal radiation exposures in our group of pregnant women did not reach the level (50 mGy) that is known to increase risk for congenital anomalies. CONCLUSION: Fetal radiation exposure in the diagnostic radiology procedures in our study did not reach risk levels that might have indicated abortion.

Fetal radiation doses and subsequent risks from X-ray examinations: should we be concerned?

Pregnant women are sometimes exposed to ionizing radiation in radiology examinations for various reasons. In such cases, the radiation dose to the conceptus and subsequent risks should be estimated. The purpose of this study was the calculation and presentation of fetal dose and subsequent risks resulted from different X-ray examinations An analytical simulation study was conducted and six common radiographies in different views and three types of special examinations were evaluated. The entrance skin exposure [ESE] was measured using a solid-state dosimeter. A Monte Carlo program was used in order to simulate different views of X-ray examinations and calculate the radiation doses received by the conceptus for every view of each examination. Then the risk of childhood cancer and small head size were calculated for different radiographies. The fetal doses and consequence risks of the small head size and childhood cancer for the radiographs of chest, skull, and sinuses were negligible but the risks of childhood cancer and small head size due to radiographies of abdomen, lumbar spine, and pelvis areas were ponderable. Results of this study can be used for the pregnant women radiographies management

Sistema on-line para o cálculo de doses fetais de pacientes e trabalhadoras ocupacionalmente expostas em radiologia diagnóstica / On-line software for the estimation of fetal radiation dose to patients and staff members in diagnostic radiology

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.

Effect of mobile phone microwaves on fetal period of BALB/ c mice in histological characteristics of hippocampus and learning behaviors

The possible risks of radio-frequency electromagnetic fields [EMF] for the living organisms and human body are a growing concern for our society. In this study, we examined the possibility of changes in working memory and hippocampal histological characteristics effects in mice brain following whole body exposure to microwave radiation. During gestation period, we exposed mice for 4 hr to Global system for mobile communications [GSM], Specific Absorption Rate [SAR] of 200 mW/kg. Pregnant control mice were sham-exposed or free in a cage without further restraining. Three month after exposure, animals were prepared for behavioral [Radial Arm Maze [RAM] and Morris Water Maze [MWM]] and histological studies. The showed that microwave exposed mice were slower than sham, and control in finding the platform. Analyses of error rates in RAM and MWM performance revealed significant differences which emphasize the effect of acute exposure to pulsed microwaves in deficit of spatial reference memory in the mice. However in this study exposed group didn't show any statistically significant loss of hippocampal CA1, CA3 neurons versus controls or sham. We conclude that there is evidence from the current study that exposure to MW radiation under parameters examined caused decrements in the ability of mice to learn the spatial memory task

Radiología diagnóstica en la embarazada: consideraciones sobre exposición a radiación y riesgo del feto / Diagnostic radiology in the pregnant: radiation exposure and risk to the fetus

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.

Dosis al feto en radiodiagnóstico / Dose to the fetus in radiodiagnostic

Se discute los efectos de la irradiación al feto y sus consecuencias, según dosis recibida, considerando la eventual suspensión de embarazo por esta causa.

Radiation risk in diagnostic radiology departments in Kuwait: should female radiation workers worry?

The International Commission on Radiological Protection [ICRP] in their 1990 report, recommended a reduction of the dose limit to occupational workers, other members of the public, and for foetal exposure. A total of 2169 personnel monitoring dose reports in respect of radiologists and other radiation workers from the radiology departments in Government Hospitals in Kuwait, randomly selected for the five year period 1991-95, were reviewed to draw conclusions on the adequacy of protection. The percentage of radiation workers exposed to different ranges of dose limits was tabulated. The results indicate the existence of adequate protection and no cause for concern for the workers and for the foetus in case of possible pregnancy, for female radiation workers

Determinaçäo da dose no feto em pacientes submetidas a radioterapia com câncer de mama / Dose determination of fetus in patients with breast cancer subjected to radiotherapy

O tratamento do câncer da mama durante a gravidez é um problema especial em oncología, uma vez que tal fato constitui elemento de importância para o prognóstico e indicaçäo terapêutica. Em certas condiçöes, o tratamento näo pode ser adiado nem a gravidez interrompida, pois acarretaria um prejuízo das chances de sobrevida para a paciente. Assim, o tratamento deve ser intensivo e, mesmo quando a associaçäo terapêutica é agressiva ao feto, esta deve ser recomendada, desde que realmente venha a ajudar a paciente e produzir o menor dano ao feto. Medidas foram feitas em diversos níveis do útero, onde o feto se localiza durante os diferentes períodos da gestaçäo, com a finalidade de definir a exposiçäo por radiaçäo secundária que o feto recebe durante o tratamento radioterápico. Para esse estudo foram efetuadas medidas em "phantom" Alderson para cada campo individualizado de irradiaçäo, em pacientes de câncer de mama tratadas por cobalto 60 e acelerador linear de 6 MV