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Background: Memantine has shown clinical utility in preventing radiation-induced cognitive impairment, but the mechanisms underlying its protective effects remain unknown. We hypothesized that abnormal glutamate signaling causes radiation-induced abnormalities in neuronal structure and that memantine prevents synaptic toxicity., Methods: Hippocampal cultures expressing enhanced green fluorescent protein were irradiated or sham-treated and their dendritic spine morphology assessed at acute (minutes) and later (days) times using high-resolution confocal microscopy. Excitatory synapses, defined by co-localization of the pre- and postsynaptic markers vesicular glutamate transporter 1 and postsynaptic density protein 95, were also analyzed. Neurons were pretreated with vehicle, the N-methyl-d-aspartate-type glutamate receptor antagonist memantine, or the glutamate scavenger glutamate pyruvate transaminase to assess glutamate signaling. For animal studies, Thy-1-YFP mice were treated with whole-brain radiotherapy or sham with or without memantine., Results: Unlike previously reported long-term losses of dendritic spines, we found that the acute response to radiation is an initial increase in spines and excitatory synapses followed by a decrease in spine/synapse density with altered spine dynamics. Memantine pre-administration prevented this radiation-induced synaptic remodeling., Conclusion: These results demonstrate that radiation causes rapid, dynamic changes in synaptic structural plasticity, implicate abnormal glutamate signaling in cognitive dysfunction following brain irradiation, and describe a protective mechanism of memantine.

The treatment of midfacial tumours with radiotherapy, chemotherapy and radio-iodine can cause nasolacrimal duct fibrosis resulting in epiphora. Nasolacrimal patency can be maintained by stenting. We report our experience of prophylatic Nunchaku stent insertion in 5 patients prior to midfacial radiotherapy. Four out of 5 patients (80%) had patent nasolacrimal ducts without any symptoms of epiphora following removal of the stents. One patient was initially asymptomatic with patent nasolacrimal duct, but subsequently developed epiphora. Nunchaku stents may provide a simple and effective way of preventing epiphora, obviate the need for nasal retrieval that is required for other nasolacrimal stents, and reduce the risk of requiring further lacrimal surgery.

The diagnostic of cancer during pregnancy is a rare and delicate situation. As the developments of the embryo and the human fetus are extremely sensitive to ionizing radiations, the treatment of these tumors should be discussed. The studies - preclinical and clinical - based mostly on exposure accidents show that subdiaphragmatic treatments are possible during pregnancy. When radiotherapy is used, phantom estimations of the dose to the fetus, confirmed by in vivo measurements are required. Irradiation and imaging techniques should be arranged to decrease as much as possible the dose delivered to the fetus and hold below the threshold of 0.1Gy., (Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.)

The pregnant trauma patient presents an important and challenging encounter for the clinical team and radiologist. In this article, we present several key aspects of the imaging workup of pregnant trauma patients, beginning with a review of the modalities that are used in this setting. Ultrasonography plays an important role in initial evaluation of the fetus but a limited role in evaluation of maternal injuries. Given that conventional radiography and computed tomography are the "workhorse" modalities for evaluation of pregnant trauma patients, radiologists must pay particular attention to radiation dose concerns. Magnetic resonance imaging can be used after the initial evaluation and for follow-up imaging, and safety concerns related to its use in pregnant patients are addressed. At imaging interpretation, radiologists must contend not only with the typical spectrum of injuries that can be seen in any trauma patient but also with pregnancy-specific injuries, such as placental abruption and uterine rupture. Particularly unusual situations, such as a ruptured ectopic pregnancy in a trauma patient, are presented. Although pregnant trauma patients are infrequently encountered, familiarity with imaging findings of injuries in these patients is essential to providing the best care for the mother and fetus., (RSNA, 2014)

OBJECTIVE. The purpose of this article is to describe how to address patients' past-and future potential-radiation exposures when making an imaging decision in a given situation. CONCLUSION. The Biologic Effects of Ionizing Radiation committee has endorsed a linear no-threshold model to explain the relationship between radiation exposure and cancer risk. This model implies that past and future potential exposures should not impact current decisions. We present an analogy that deconstructs these counterintuitive conclusions and facilitates translation of key radiation risk principles to practice.

Background: The International Commission of Radiology recommends a pregnancy screening test to all female patients of childbearing age who will undergo a radiological study. Radiation is known to be teratogenic and its effect is cumulative. The teratogenic potential starts at doses close to those used during these procedures. The prevalence of positive pregnancy tests in patients undergoing electrophysiological studies and/or catheter ablation in our midst is unknown., Objective: To evaluate the prevalence of positive pregnancy tests in female patients referred for electrophysiological study and/or radiofrequency ablation., Methods: Cross-sectional study analyzing 2966 patients undergoing electrophysiological study and/or catheter ablation, from June 1997 to February 2013, in the Institute of Cardiology of Rio Grande do Sul. A total of 1490 procedures were performed in women, of whom 769 were of childbearing age. All patients were screened with a pregnancy test on the day before the procedure., Results: Three patients tested positive, and were therefore unable to undergo the procedure. The prevalence observed was 3.9 cases per 1000 women of childbearing age., Conclusion: Because of their safety and low cost, pregnancy screening tests are indicated for all women of childbearing age undergoing radiological studies, since the degree of ionizing radiation needed for these procedures is very close to the threshold for teratogenicity, especially in the first trimester, when the signs of pregnancy are not evident.

The incidence of lung cancer during pregnancy is very low, but it is becoming more frequent in industrialized countries both because of the increase in smoking in young women and because women are becoming pregnant later in life. Usually, the cancer has a poor prognosis due to the presence of metastatic disease at the time of diagnosis. Diagnosis and management are delicate, and should deal with the gestational age, the maternal prognosis, the fetal toxicity of treatments, but also with the worsening of maternal prognosis and the risk of neoplastic cells being transmitted to the fetus in case of delayed treatment. Psychological and ethical considerations complicate the decision process. We present a review of the epidemiology, clinical characteristics, management, and prognosis concerning lung cancer during pregnancy. Finally, it is important to remember that young women with lung cancer should be advised to use a reliable form of contraception., (Copyright © 2012 SPLF. Published by Elsevier Masson SAS. All rights reserved.)

For the modern practitioner of women's imaging, achieving a balance between the positive diagnostic benefits available from current medical imaging on the one hand, and the potentially deleterious effects of ionizing radiation exposure on the other, has become a central issue. Increased public and professional awareness of the side effects of radiation now require a comprehensive understanding of the facts involved, the various risks to which patients are exposed, and the measures that can be implemented to minimize these risks. The major challenges posed by pregnancy, radiosensitive breast tissue, lactation, and an inability to easily exclude ovaries from the imaging field make female patients particularly vulnerable to medical imaging radiation exposure. The nature of this vulnerability changes frequently and depends on the imaging being performed, the age of the patient, and the clinical situation. For this reason, attention to gynecologic imaging radiation exposure across the whole life span is vitally important.

Radiation environment in extended duration exploration missions is scrutinized in the context of the probability of the risks of deterministic and stochastic effects of radiation. Though the probability of severe radiation damage due to solar flare is very low, nonetheless it is requisite that the crew must be provided with appropriate, including pharmacological safeguards. The current nomenclature of radiation protectors composes short-term agents against acute radiation damage. Among the others, preparation B-190 is distinguished by particularly high effectiveness and universal action, and good tolerance even when organism is exposed to the extreme factors of space flight Regimen of B-290 therapy alone and with combination with aminothiol preparations have been developed to render treatment following multiple solar events. Effectiveness of radioprotectors can be increased substantially by local shielding of the abdomen and pelvis. The most promising nonspecific stimulators of total resistance of organism are riboxin (inosin) and combined preparation aminotetravit as well as vitamins tocopherol and retinol. Therapy combining B-190 with riboxin and aminotetravit is also under discussion. Cytokine neipogen is also viewed as a candidate agent for early therapy. Concern is raised about possible development of chronic oxidative stress in long-duration exploration missions. Highlighted is the significance of adequate nutrition supplemented with fresh vegetables as a source of the most valuable bioflavonoids. Antioxidants L-selenomethionine and melatonin proved their effectiveness against heavy nuclei of galactic radiation. An open issue is how to make natural antioxidants beneficial to oxidative stress control and attenuation of low-intensity galactic radiation.

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 catheterization 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 catheterization 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 catheterization laboratory and thus do not justify precluding pregnant physicians from performing procedures in the cardiac catheterization laboratory. However, radiation exposure among pregnant physicians should be properly monitored and adequate radiation safety measures are still warranted., (Copyright © 2011 Wiley-Liss, Inc.)

Introduction: The effect of radiation on the fetus has been derived primarily from animal studies and human exposures to diagnostic and therapeutic radiation as well as atomic bomb exposure. Given the variety of sources, there is controversy over the dose of radiation in addition to the other environmental conditions that surrounded these events and their relationship to exposure today., Methods: The effects of ionizing radiation on the fetus, the prenatal period, parental exposure, the pregnant clinician, and the pregnant patient are discussed in the context of their exposure to radiation., Results: The fetus is most sensitive to radiation effects between 8 and 15 weeks of pregnancy. Stepping away from the table and using movable shields help reduce the exposure by a factor of four for every doubling of the distance between the operator and the radiation source., Conclusion: Proposed guidelines for pregnancy during vascular residency training involving fluoroscopic procedures can help bring about awareness, clarify maximal exposure, and better delineate the role of the pregnant resident., (Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

A recurring source of contention between clinicians and radiologists continues to be examination appropriateness when imaging pregnant patients. With the multitude of references on potential radiation risks to the fetus, radiologists tend to be cautious and hesitant about exposing the fetus to radiation. This tendency is often interpreted by referring physicians as intrusion into and delay in the care of their patients. The risk burden of radiation exposure to the fetus has to be carefully weighed against the benefits of obtaining a critical diagnosis quickly and using a single tailored imaging study. In general, there is lower than expected awareness of radiation risks to the fetus from imaging pregnant patients. Modalities that do not use ionizing radiation, such as ultrasonography and magnetic resonance imaging, should be the preferred examinations for evaluating an acute condition in a pregnant patient. However, no examination should be withheld when an important clinical diagnosis is under consideration. Exposure to ionizing radiation may be unavoidable, but there is no evidence to suggest that the risk to the fetus after a single imaging study and an interventional procedure is significant. All efforts should be made to minimize the exposure, with consideration of the risk versus benefit for a given clinical scenario.

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.

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.

Irradiation of salivary glands during radiotherapy treatment of patients with head and neck cancer evokes persistent hyposalivation. This results from depletion of stem cells, which renders the gland incapable of replenishing saliva to produce acinar cells. The aim of this study was to investigate whether it is possible to expand the salivary gland stem/progenitor cell population, thereby preventing acinar cell depletion and subsequent gland dysfunction after irradiation. To induce cell proliferation, keratinocyte growth factor (DeltaN23-KGF, palifermin) was administered to C57BL/6 mice for 4 days before and/or after local irradiation of salivary glands. Salivary gland vitality was quantified by in vivo saliva flow rates, morphological measurements, and a newly developed in vitro salisphere progenitor/stem cell assay. Irradiation of salivary glands led to a pronounced reduction in the stem cells of the tissues, resulting in severe hyposalivation and a reduced number of acinar cells. DeltaN23-KGF treatment for 4 days before irradiation indeed induced salivary gland stem/progenitor cell proliferation, increasing the stem and progenitor cell pool. This did not change the relative radiation sensitivity of the stem/progenitor cells, but, as a consequence, an absolute higher number of stem/progenitor cells and acinar cells survived after radiation. Postirradiation treatment with DeltaN23-KGF also improved gland function, and this effect was much more pronounced in DeltaN23-KGF pretreated animals. Post-treatment with DeltaN23-KGF seemed to act through accelerated expansion of the pool of progenitor/stem cells that survived the irradiation treatment. Overall, our data indicate that DeltaN23-KGF is a promising drug to enhance the number of salivary gland progenitor/stem cells and consequently prevent radiation-induced hyposalivation. Disclosure of potential conflicts of interest is found at the end of this article.

Use of diagnostic imaging studies for evaluation of pregnant patients with medical conditions not related to pregnancy poses a persistent and recurring dilemma. Although a theoretical risk of carcinogenesis exists, there are no known risks for development of congenital malformations or mental retardation in a fetus exposed to ionizing radiation at the levels typically used for diagnostic imaging. An understanding of the effects of ionizing radiation on the fetus at different gestational stages and the estimated exposure dose received by the fetus from various imaging modalities facilitates appropriate choices for diagnostic imaging of pregnant patients with nonobstetric conditions. Other aspects of imaging besides radiation (ie, contrast agents) also carry potential for fetal injury and must be taken into consideration. Imaging algorithms based on a review of the current literature have been developed for specific nonobstetric conditions: pulmonary embolism, acute appendicitis, urolithiasis, biliary disease, and trauma. Imaging modalities that do not use ionizing radiation (ie, ultrasonography and magnetic resonance imaging) are preferred for pregnant patients. If ionizing radiation is used, one must adhere to the principle of using a dose that is as low as reasonably achievable after a discussion of risks versus benefits with the patient., (RSNA, 2007)

In this 2-part article, the authors address the need to put in perspective the risks of radiation exposure in the rapidly changing field of radiology, considering the current state of knowledge of effects at low levels. The article is based on the content of the refresher course RC 516 presented at the Radiological Society of North America's 2005 annual meeting. In part 1, the authors presented a brief review of epidemiologic studies, a discussion of typical radiation doses experienced in medicine by both patients and professionals, and the description of practical approaches to reduce unnecessary exposures. Part 2 addresses a special concern for the unborn and discusses advisory and regulatory cancer risk estimates based mainly on epidemiologic studies. The limitations of epidemiologic studies at low-level exposures and recent new findings in radiobiology, some of which are summarized, challenge the notion that any amount of radiation causes adverse effects.

Health physicists and knowledgeable clinicians have the responsibility to counsel women of reproductive age about the reproductive risks of ionizing radiation exposure before conception or during pregnancy. It is important to realize that lay individuals have many misconceptions about the reproductive risks of ionizing radiation. Many patients who have already had or will undergo some type of radiological test are apprehensive about the reproductive and developmental risks of diagnostic radiological procedures. Epidemiological studies and animal studies indicate that high exposures of ionizing radiation can cause miscarriage, congenital malformations, growth retardation, stillbirth, and cancer. With the exception of cancer, there are threshold exposures for those outcomes, with exposures below certain radiation doses not increasing the reproductive or developmental risks. The threshold exposure for birth defects at the most sensitive stage of development is 0.2 Gy, and the threshold for growth retardation and miscarriage is even higher. However, embryonic loss can occur from low exposures during the preimplantation and presomite stages of development ("the all or none period"). This is a stage when the embryo is more likely to die than survive malformed. The most sensitive period for the induction of mental retardation is from the 8th week to the 15th week of gestation. The threshold for deterministic effects increases after early organogenesis and also as the exposure is protracted, e.g., with radionuclides or multiple radiological procedures. Awareness that the threshold dose for developmental effects increases as the fetus develops complicates counseling because we do not have definitive data on threshold exposures at all stages of gestation. Ionizing radiation exposures prior to pregnancy represent a very low risk for the increased incidence of genetic disease in the offspring of the parents who have had radiation exposures to the ovary or testes. Counseling patients requires knowledge of embryology, genetics, radiation teratology, and the principles of teratology in order for the counselor to provide sympathetic, accurate, scholarly advice.

Unstable fractures of the posterior pelvic ring during pregnancy are rare. Pregnancy increases the high demands on the therapy of these types of fractures. The aim of the therapeutic strategy in such a situation is a good functional outcome of the mother without influencing the fetal health. Some osteosynthetic techniques result in good functional outcomes, but they are associated with high amounts of ionizing radiation. We report the case of a pregnant woman who sustained a vertical unstable fracture of the posterior pelvic ring as a result of a traffic accident. The fracture was treated surgically by open reduction and internal fixation with two transiliac reconstruction plates with minimal radiographic exposure to the fetus. One year later, a good functional result concerning the mother was shown. The child was healthy without any signs of prenatal impairment. Surgical treatment of an unstable fracture of the pelvic ring during pregnancy is possible with a justifiable risk to the mother and the child. Consideration of the expected fetal radiation exposure in the course of the therapy is particularly recommended. Using minimal doses of ionizing radiation, the described method results in a good clinical outcome of the mother while simultaneously reducing the radiation exposure of the fetus to an acceptable level.

During high-altitude flight, the cosmic radiation dose rate in an airliner is greater than it is at ground level. For a casual traveler, the impact on pregnancy from cosmic radiation exposure during flight is trivial. Pregnant frequent flyers, pilots, and flight attendants can, however, receive exposures that exceed current recommended values if they do not appropriately modify their work schedules. In addition to the galactic cosmic-ray background that is the source of this radiation, severe disturbances on the sun may cause eruptions that significantly raise radiation levels at airliner altitudes for brief periods, possibly having an impact even on casual travelers. This article will help obstetrician-gynecologists provide advice to their pregnant patients about in-flight radiation risks. That advice should be influenced by an understanding of recommended radiation exposure limits and a perspective on how those limits relate to the potential for real harm. Resources provided by the U.S. Federal Aviation Administration and others to help pregnant women and their physicians make informed decisions about the acceptability of this type of exposure are described.

The finite difference time domain (FDTD) method in combination with a well established frequency scaling method was used to calculate the internal fields and current densities induced in a simple model of a pregnant woman and her foetus, when exposed to hand-held metal detectors. The pregnant woman and foetus were modelled using a simple semi-heterogeneous model in 10 mm resolution, consisting of three different types of tissue. The model is based on the scanned shape of a pregnant woman in the 34th gestational week. Nine different representative models of hand-held metal detectors operating in the frequency range from 8 kHz to 2 MHz were evaluated. The metal detectors were placed directly on the abdomen of the computational model with a spacing of 1 cm. Both the induced current density and the specific absorption rate (SAR) are well below the recommended limits for exposure of the general public published in the ICNIRP Guidelines and the IEEE C95.1 Standard. The highest current density is 8.3 mA m(-2) and the highest SAR is 26.5 microW kg(-1). Compared to the limits for the induced current density recommended in the ICNIRP Guidelines, a minimum safety factor of 3 exists. Compared to the IEEE C95. 1 Standard, a safety factor of 60 000 for the specific absorption rate was found. Based on the very low specific absorption rate and an induced current density below the recommended exposure limits, significant temperature rise or nerve stimulation in the pregnant woman or in the foetus can be excluded.

In the UK, Regulation 8(5) of the Ionising Radiation Regulations 1999 (In: Work with ionising radiation. London: HSE Books, 2000) requires employers to ensure that the dose to the foetus of a pregnant worker is unlikely to exceed 1 mSv. Risk assessments are required which are capable of predicting the total foetal dose. Work involving 131I is a particular problem. Foetal dose coefficients from the maternal intake of 131I for all stages of pregnancy have been published (Phipps AW, Smith TJ, Fell TP, Harrison JD. Doses to the embryo/fetus and neonate from intake of radionuclides by the mother. NRPB contract research report 397/2001. Didcot, Oxon.: National Radiological Protection Board (NRPB), 2001. Available on website www.hse.gov.uk/research/crr_pdf/2001/crr01397.pdf), and range from 0.08 microSv x kBq(-1) at conception to 55 microSv x kBq(-1) at week 35. This paper examines one aspect of work in a nuclear medicine department in which the source of 131I is uncontrolled to determine whether the risk assessment indicates that restrictions should apply to a pregnant member of staff. Following in-patient treatment with 131I, rooms are checked and decontaminated before being decontrolled. Cleaning staff were monitored immediately after the cleaning process with hand-held detectors and by whole-body monitoring. Total body contamination ranged up to 3.2 kBq; after a change of clothing, the maximum remaining activity was 0.68 kBq. Acquired contamination correlated with the total activity administered to the patient. Hand-held monitoring rarely detected contamination. Whole-body monitoring indicated that the levels of contamination encountered could lead to a dose limit for the foetus being exceeded. These levels are very difficult to detect with hand-held monitoring. The conclusion to be drawn is that pregnant staff should be excluded from situations in which accidents could arise, or where the source of 131I is uncontrolled or unpredictable.

Neonatal X-irradiation induces permanent abnormalities in cerebellar cortex cytoarchitecture and neurochemistry, as well as impairment in motor gait. The aim of the present work was to examine the potential protective properties of WR-2721 (Amifostine, Ethyol), a free radical scavenger, against the above mentioned alterations by using a previously described neuroprotection assessment protocol. Pre-irradiation treatment with amifostine was effective in partially preventing the cerebellar morphological damage and the motor gait impairment induced by ionizing radiation. No changes in cerebellar noradrenaline (NA) levels were detected in amifostine-treated irradiated animals. These results suggest that it is possible to counteract radiation-induced damage in the cerebella and motor gait of neonatal rats through oxygen free radical scavenger administration prior to irradiation. The presence of the agent before the injury occurs, favors the efficacy of amifostine neuroprotective activity. Clinical implications of this model are related to the daily exposure of many people to different sources of radiation (accidental, diagnostical or therapeutical).

The objectives of the present study were to (a) estimate the conceptus radiation dose and risks for pregnant women undergoing posteroanterior and anteroposterior (AP) chest radiographs, (b) study the conceptus dose as a function of chest thickness of the patient undergoing chest radiograph, and (c) investigate the possibility of a conceptus to receive a dose of more than 10 mGy, the level above which specific measurements of conceptus doses may be necessary. Thermoluminescent dosimeters were used for dose measurements in anthropomorphic phantoms simulating pregnancy at the three trimesters of gestation. The effect of chest thickness on conceptus dose and risk was studied by adding slabs of lucite on the anterior and posterior surface of the phantom chest. The conceptus risk for radiation-induced childhood fatal cancer and hereditary effects was calculated based on appropriate risk factors. The average AP chest dimension (d(a)) was estimated for 51 women of childbearing age from chest CT examinations. The value of d(a) was estimated to be 22.3 cm (17.4-27.2 cm). The calculated maximum conceptus dose was 107 x 10(-3) mGy for AP chest radiographs performed during the third trimester of pregnancy with maternal chest thickness of 27.2 cm. This calculation was based on dose data obtained from measurements in the phantoms and d(a) estimated from the patient group. The corresponding average excess of childhood cancer was 10.7 per million patients. The risk for hereditary effects was 1.1 per million births. Radiation dose for a conceptus increases exponentially as chest thickness increases. The conceptus dose at the third trimester is higher than that of the second and first trimesters. The results of the current study suggest that chest radiographs carried out in women at any time during gestation will result in a negligible increase in risk of radiation-induced harmful effects to the unborn child. After a properly performed maternal chest X-ray, there is no need for individual conceptus dose estimations.

ICR mice fetuses in the organogenesis stage were used to clarify experimentally the mechanism of the protective effect of vitamin E derivant (TMG: 2-(alpha-D-Glucopyranosyl) methyl-2, -5, -7, -8-Teramethylchorman-6-working woman) on the effects of radiation. The authors paid careful attention to radiation, and the radioprotective effects of TMG on the induction of malformations was examined. Radiation is an important consideration because of its widespread use in the areas of medicine, nuclear energy, and industry. Malformations induced by radiation at the organogenesis stage, skeletal malformations, and the effects at the cellular level of embryos were examined in this research. Further, the mechanism of the protection effect of TMG against radiation-induced malformations was analyzed and observed experimentally. Thus, this study was done to provide fundamental data on the radioprotective agent TMG. It was clear that TMG exerted radioprotective effects against embryonic death and the rate of teratogenesis when administered before exposure. Such effects were also exerted against skeletal malformations and fetal body weight. In summary, radioprotective effects were observed at the whole-body level as well as at the cellular level.

Detrimental effects on the thyroid of the developing fetus as a result of iodine-131 treatment for thyrotoxicosis of the mother in the first trimester of pregnancy are discussed. Dose estimations under typical clinical circumstances yield a fetal thyroid dose of 100- 450 Sv. This dose may increase considerably if the blood concentration of (131)I in the mother remains high. Under such circumstances there may be fetal thyroid dysfunction, which can lead to severe abnormalities.

Purpose: To describe language used in consent documents at one academic medical center to inform women participating in studies of potential reproductive and fetal risks., Method: The authors reviewed consent document language describing reproductive and fetal risks in 114 approved protocols. Protocols were identified as being of high, low, or unknown risk based upon FDA drug-risk and radiation-risk categories., Results: Although most consent documents advised women against participating for one or more pregnancy-related reasons, specific information about reproductive or fetal risks was included in fewer consent documents: 8 (73%) of the high-risk studies, 12 (40%) of the low-to-moderate-risk studies, and 29 (40%) of the unknown-risk studies., Conclusions: Investigators often omit fetal risk information from consent documents. Full disclosure of reproductive and fetal risks in consent documents and discussions can be taught and modeled during the research training period. The authors present a template with language that can be used in consent documents and recommend ongoing discussion of reproductive and fetal risks with women subjects throughout the study period.

Original MP-33 metabolic drug has inductive action on intracellular levels of glutathione (GSH) and GSH-related enzymes (glutathione peroxidase-GPx, glutathione S-transferase-GST) of animals and human (liver, heart, erythrocytes). Treatment of Wistar male rats with MP-33 per os (6 mg/kg) 30 min before gamma-irradiation with a dose of 7 Gy results in 35% survival and increasing of mean life. In "mother-foetus" system the induction of intracellular level of GSH, GST and GPx by MP-33 leads to enhancement of foetus radioresistance. In contrast to MP-33 us of GSH (6 and 100 mg/kg) is not effective. Perspective of MP-33 us in relation to radioecological crisis is discussed.

Hodgkin's disease diagnosed during pregnancy poses a dilemma as there are risks of abortion and fetal malformation with the use of radiotherapy and chemotherapy. A patient with Hodgkin's disease during pregnancy treated with radiotherapy is presented.

Rationale and Objectives: To investigate the possibility of an embryo to receive a dose of more than 10 cGy, the threshold of malformations induction in embryos reported by the International Commission on Radiological Protection, during barium enema examinations., Methods: Thermoluminescent dosimeters were placed in a phantom to calculate the depth-to-skin conversion coefficient needed for dose estimation at the average embryo depth in patients. Barium enema examinations were performed in 20 women of childbearing age with diagnostic problems demanding longer fluoroscopy times. Doses at 6 cm, the average embryo depth, were determined by measurements at the patients' skin followed by dose calculation at the site of interest., Results: The range of doses estimated at embryo depth for patients was 1.9 to 8.1 cGy. The dose always exceeded 5 cGy when fluoroscopy time was longer than 7 minutes., Conclusion: The dose at the embryo depth never exceeded 10 cGy. This study indicates that fluoroscopy time should not exceed 7 minutes in childbearing-age female patients undergoing barium enema examinations.

Considering that there's a lack of information concerning the risks of radiation exposure in pregnancy, the author identifies such risks and estimates its magnitude. He underlines the fact that radiological examinations deliver lower doses in relation to those that can be proved to be malefic to the embryo, both in the somatic and genetic plan.

The International Commission on Radiological Protection has recently recommended a supplementary dose limit of 2 mSv to the abdominal surface of a pregnant member of staff in order to provide protection to her fetus comparable to that in members of the public, whose annual limit is recommended to be 1 mSv. In order to determine whether this apparent attenuation factor of 50% is appropriate for nursing and imaging staff exposed to nuclear medicine patients, estimates were made of the ratios of the maternal abdominal surface to fetal dose appropriately weighted for time, distance and dose rate. Thermoluminescent dosimeter (TLD) measurements were made at various depths in an anthropomorphic phantom irradiated at different distances by a distributed source of either technetium-99m or iodine-131 in order to determine the corresponding attenuation factors at the average fetal midline depth. Dose estimates were based on these factors and on published values of dose rate and exposure times for nursing and imaging staff at these distances from the patient. Fetal doses to nursing staff caring for an adult 99mTc patient were estimated to vary from 86 microSv to 1.6 microSv, with the corresponding ratio of the abdominal surface to fetal dose varying from about 1.8:1 to 1.5:1 as the patient became less dependent on nursing care and the mean distance from the patient increased. Fetal doses to imaging staff varied from 1.12 microSv to 0.17 microSv for three types of 99mTc scan, but the ratio only varied from 1.4:1 to 1.3:1. Fetal doses to imaging staff were estimated to be 6.7 microSv and 9.0 microSv for a whole-body scan of a thyroid cancer patient after 131I ablation and therapy respectively, and the ratio was 1.3:1 for both types of scan. It was concluded that for a pregnant ward nurse or imaging technologist exposed to an adult or paediatric patient administered 99mTc or 131I, a dose limit of 1.3 mSv to the maternal abdominal surface will restrict their fetal dose to 1 mSv. A pregnant imaging technologist should perform no more than six adult 99mTc studies or one 131I whole-body scan per day, and may have to wear a more sensitive personal dosimeter than a film badge.

The antiteratogenic effects of PSK, a biological response modifier, were examined using histological and developmental analysis. The whole bodies of pregnant mice were irradiated with X-rays and injected with PSK within ten minutes after irradiation on day 7 of gestation (E7). The foetuses on E18 were examined and a high incidence of malformations were observed in X-ray irradiated embryos. Microphthalmia was the most frequent malformation. PSK administration suppressed the X-ray irradiation-induced ocular anomalies in not only the frequency, as deduced by external observation, but also in histopathological changes in the retina, lens, and cornea. In particular, the incidence of lens aplasia was significantly decreased by PSK administration. Developmental analysis using E10 and E13 embryos revealed that the decrease in the incidence of histopathological changes was first observed within 72 hours after PSK administration. In addition, X-ray irradiation-induced early foetal death (E10-13) was also suppressed by PSK administration. The possible mechanisms of the antiteratogenic effects of PSK are discussed.

Because of the increased recognition of the lifetime risks from the exposure to low levels of ionizing radiation, it is recommended that alterations be made to the currently accepted guidelines for prescribing radiographs for pregnant patients. Particularly so, because it has been shown that optimal radiographic practices in dental schools and dental offices are not universally followed.

Controlling irradiation of the conceptus, the child and the adolescent due to radiodiagnosis techniques is of particular importance since these age groups are more sensitive to ionizing irradiation than adults. In addition the conceptus (embryo or foetus) often receives whole-body irradiation. Based on the data in the literature, it can only be demonstrated that, under normal diagnostic conditions, irradiation risks do exist. However, the aim of applying ethical standards based on the "ALARA" concept is to reduce the potential irradiation-related risk and to sustain a sufficiently high level of awareness of the potential danger in health careworkers.

Breast cancer treatment during pregnancy involves a host of psychosocial, ethical, religious, and even legal considerations, as well as medical multidisciplinary decisions, since the effect of treatment on the fetus must be considered. For example, breast or chest wall radiotherapy should be avoided. The absorbed fetal dosage is at least 5 cGy early in pregnancy and increases to several hundred cGy late in pregnancy to the fetal part immediately below the diaphragm. In the second and third trimesters, chemotherapy is associated with intrauterine growth retardation and prematurity in about half of the babies; the risk of birth defects is a concern in the first several weeks. Typical anesthetic agents readily reach the fetus but are not known to be teratogenic. Although abortion will allow full and comprehensive treatment to the mother, it is not known whether the procedure itself is therapeutic. Early in pregnancy, abortion deserves strong consideration, since the effects of treatment on the fetus will not be a consideration. The poor prognosis of pregnancy-associated breast cancer in the past is probably attributable to a combination of initial delay of diagnosis and possibly to unfavorable biologic characteristics of the hormonal milieu of pregnancy. When pregnant patients are matched stage for stage with controls, survivals seem equivalent, although pregnant patients present with more advanced disease.

On the basis of screening of 15939 newborns at the maternity homes of Kiev after the accident at the Chernobyl atomic station it was found that the number of children with congenital malformation of the locomotor apparatus in 1991-1992 increased by 28.7% as compared with the data of the first postaccident years (1986-1987). Congenital pathology of the hip joint (dysplasia in average 23.5 per 1000 births, hip dislocation 3.6:1000) and foot deformity (7.9:1000) had the highest incidence with a tendency to increase at the latest years.

Balloon valvotomy by means of the Inoue technique was attempted in seven pregnant (5 to 9 months) patients with severe mitral stenosis; the mean age of the patients was 32 +/- 8 years, and all had a two-dimensional echocardiographic mitral valve score of < 8. Indications for Inoue balloon valvotomy included severe symptomatic mitral stenosis with a Doppler mitral valve area < or = 1 cm2 and heart failure refractory to medical therapy, or absolute contraindications for the use of beta-blockade; Inoue valvotomy was also indicated for patients who lived a long distance from the hospital. Inoue balloon valvotomy was performed with no angiography and total pelvic and abdominal shielding; the balloon catheter was introduced into the right atrium without the aid of fluoroscopy, which was used for the transseptal puncture. Stepwise two-dimensional echocardiographic Doppler mitral valve dilatation was done. After Inoue balloon valvotomy the mean Doppler mitral valve area increased from 0.8 +/- 0.1 to 2.0 +/- 0.3 cm2 (p < 0.01) and by two-dimensional echocardiography from 0.8 +/- 0.2 to 1.9 +/- 0.3 cm2 (p < 0.01), with no significant Doppler residual stenosis (defined as mitral valve area < or = 1.5 cm2). The mean total fluoroscopy time was 16 +/- 7 minutes. The degree of mitral regurgitation increased in two patients from grade 1+/4+ to grade 2+/4+ and from grade 0+/4+ to grade 2+/4+, respectively. There was no mortality or significant morbidity. Pregnancy was uneventful in all patients, and all were delivered of normal babies without complications.(ABSTRACT TRUNCATED AT 250 WORDS)