Risks to the fetus from diagnostic imaging during pregnancy: review and proposal of a clinical protocol

Pregnancy, Hip Pain, and Total Hip Replacement

➤ Young women who are 15 to 45 years of age and undergo total hip replacements are at increased risk for revision compared with women >75 years of age.➤ Among women of childbearing age with a total hip replacement, 12% to 17% will later have at least 1 pregnancy.➤ Young women who undergo total hip replacement do not have an increased risk of pregnancy complications.➤ Of the 60% of women who experienced pain with a total hip replacement during pregnancy, 21% had persisting pain, and 4% reported the pain as severe.➤ Women who have a total hip replacement and later experience pregnancy and childbirth have no increased risk of pregnancy complications or increased revision rates; there was no effect of the mode of delivery on revision rates or complications including fracture, dislocation, or loosening, according to the limited studies available.

Radiation exposure in pregnancy: outcomes, perceptions and teratological counseling in Turkish women

BACKGROUND

Fetal effects of radiation are associated with the gestational week of exposure, dose, and duration of exposure, but the perception of risk of radiation in expecting mothers is greater than the actual risk of physical effects.

OBJECTIVES

Evaluate the overestimation of the teratogenic risk in women exposed to radiation and the role of teratological counseling in minimizing preconceptions.

DESIGN

Analytical, cross-sectional.

SETTING

Tertiary care center, genetic diseases diagnosis center.

PATIENTS AND METHODS

Out of 10 784 people who applied for teratological consultation between 2009 and 2018, pregnant women meeting inclusion criteria and exposed to radiation were selected as the study group; pregnant women without radiation exposure were selected as the control group. Two subgroups of the study group based on the week and dose of exposure were also analyzed.

MAIN OUTCOME MEASURES

Abortion rate, termination recommendation rates before and after teratological counseling.

SAMPLE SIZE

461 pregnant exposed to radiation; 213 pregnant women without radiation exposure.

RESULTS

Preterm birth and termination rates differed significantly between cases and controls (P=.038, P=.019, respectively). Termination recommendation at the first examination was more frequent for both the week of exposure overall and dose subgroups comparing cases and controls (P<.001). In the comparison of subgroups by week of exposure, only the miscarriage rate was statistically significant (P=.007). After teratological counseling termination decision rates were significantly decreased (P<.001).

CONCLUSION

Subjective perceptions about the risks of radiation may lead to the termination of an otherwise wanted pregnancy. Teratological counseling is crucial for the prevention of termination of pregnancy, clarifying misinformation, and minimizing anxiety.

LIMITATIONS

With the exception of measurable values as calculated doses of radiation, the conclusions are mostly derived from medical records and subjective responses of pregnant women. The termination rates in our study probably do not reflect the whole population.

CONFLICT OF INTEREST

None.

X-RAY AND MOLECULAR IMAGING DURING PREGNANCY AND BREASTFEEDING-WHEN SHOULD WE BE WORRIED?

Some of the ethically most sensitive issues in radiation protection arise at imaging of pregnant-and potentially pregnant-patients and of newborn. This article reviews the current literature and recommendations on imaging during pregnancy and breastfeeding. Risks related to alternative non-ionizing radiation methods are also considered. With few exceptions, exposure of the fetus through radiography, computed tomography (CT) and nuclear medicine imaging can be limited to safe levels, although studies such as abdominal-pelvic CT cannot avoid significant exposure to fetuses. Eight to 10 weeks post-conception, the fetus has a thyroid which starts to concentrate iodide having crossed the placenta barrier resulting in unacceptably high doses to the fetal thyroid after administration of 131I- and even 123I-iodide and other radiopharmaceuticals with a high content of free radioiodine. Many radiopharmaceuticals are excreted through breast milk. Breastfeeding interruption recommendations should be followed to keep the effective dose to the infant below 1 mSv.

Sporadic cauda equina hemangioblastoma: surgical management in a pregnant woman

Hemangioblastoma is a rare benign vascular tumour of the central nervous system that occurs either sporadically or in association with Von Hippel-Lindau syndrome. Hemangioblastoma can be found throughout the central nervous system and usually present with late manifestations due to their slow growth rate. Cauda equina hemangioblastomas are extremely rare, and in the literature, no cases are reported on the surgical management of pregnant patients with this condition. We report the case of a young woman with back pain and sphincter dysfunctions in whom an L1-L2 hemangioblastoma was diagnosed. We describe the perioperative and surgical strategies we adopted to successfully treat the patient and preserve the fetus well-being.

MRI in pregnant patients with suspected abdominal and pelvic cancer: a practical guide for radiologists

The incidence of abdominal and pelvic cancer in pregnancy is low, but it is rising as the population of pregnant women gets older. Depending on disease stage, gestational age and patient's preference, active surveillance as well as surgery and chemotherapy are feasible options during pregnancy. Correct diagnosis and staging of the tumor is crucial for choosing the best therapeutic approach. Moreover, a reproducible modality to assess the treatment response is requested. Magnetic resonance imaging (MRI) is commonly used with good results for the local staging and treatment response evaluation of most abdominal and pelvic cancers in nonpregnant patients, and it is considered relatively safe during pregnancy. The purpose of this article is to analyze the most relevant topics regarding the use of MRI in pregnant women with abdominal and pelvic cancer. We discuss MRI safety during pregnancy, including the use of gadolinium-based contrast agents (GBCAs), how to prepare the patient for the exam and MRI technique. This will be followed by a brief review on the most common malignancies diagnosed during pregnancy and their MRI appearance.

Unsuspected Pregnancies in Hysterosalpingography: Implementation and Review of a Multi-Institutional Pre-Procedural Pregnancy Screening Protocol

PURPOSE

Owing to the increasing average age of first-time mothers, as well as advances in assistive reproductive technology, the number of hysterosalpingography (HSG) requests has continued to rise. This increases the likelihood of patients presenting with unsuspected early pregnancies prior to HSG. Currently, there is no standard of practice for the pre-procedural screening of pregnancy prior to HSG, with most institutions using patient-reported pregnancy status and unreliable menstrual cycle dating methods. We implemented a multi-institutional pre-procedural pregnancy screening protocol in order to determine the rate of unsuspected pregnancies prior to HSG and improve the quality and safety of these procedures.

METHODS

Following multi-institutional and multidisciplinary input, a consensus protocol was formulated and implemented across 9 institutions in the Lower Mainland of British Columbia, Canada. Subsequent tracking of pregnancy testing was then performed over a period of 3 years.

RESULTS

Pre-implementation review of protocols demonstrated large disparities between institutions. A total of 6333 HSG examinations were scheduled in the review period following implementation. Of these, 10 patients were found to have positive pregnancy tests (0.16%), despite self-reporting that they were not pregnant or had recent menstrual bleeding.

DISCUSSION

Hysterosalpingography is contraindicated in pregnancy, yet we identified 10 unsuspected pregnancies in patients who would have otherwise undergone HSG examinations with existing guidelines. While there remains insufficient data on the deleterious effects of performing HSG on an unsuspected pregnancy, the potential physical, economical, and psychosocial consequences of performing an HSG during pregnancy are sufficient to merit consideration of relatively inexpensive routine pregnancy screening prior to HSG.

Effect of radiologist pregnancy on the performance of pediatric fluoroscopic studies: a survey of Society for Pediatric Radiology members

BACKGROUND

To our knowledge, the fluoroscopic practice patterns of pregnant diagnostic radiologists have not been documented.

OBJECTIVE

To describe the fluoroscopic practice patterns during pregnancy among members of the Society for Pediatric Radiology (SPR) and potential impact on career and professional relationships.

MATERIALS AND METHODS

After approval from the SPR, we sent all 1,847 SPR members an email link to an anonymous online survey that queried how pregnancy affects a practicing radiologist who performs fluoroscopy.

RESULTS

Of the 398 responses (65% female, 35% male), most female respondents (78%) reported having been pregnant while practicing radiology and the majority (85%) performed fluoroscopy during pregnancy. Most performed fluoroscopy during all three trimesters (first 78%, second 90%, third 87%) and the majority (81%) used double-lead. Forty-six percent indicated that their fluoroscopic responsibilities during pregnancy were stressful. Of those who opted to perform fewer fluoroscopy studies, 20% indicated that it impacted negatively on their career or professional relationships. After witnessing a pregnant co-worker perform fewer fluoroscopic studies, 11% (4% male; 16% female; P<0.05) of respondents observed a subsequent negative impact on the co-worker's career or professional relationships.

CONCLUSION

The majority of responding female SPR members had performed fluoroscopy during pregnancy and most performed fluoroscopy during their entire pregnancy with double-lead. Differences between self-reported adversity and observed adversity of performing less fluoroscopy during pregnancy speak to the lack of awareness of the issues, particularly among male colleagues. A clear policy with regard to performing fluoroscopy during pregnancy for all radiologists in every department is necessary.

Management of Severe Traumatic Brain Injury in Pregnancy: A Body with Two Lives

Traumatic brain injury is the major contributing factor in non-obstetric mortality in developing countries. Approximately 20% of maternal mortality is directly correlated to injuries. Road traffic accidents and domestic violence are the most common nonlethal injuries that can threaten either the maternal or foetal life, and such events occur in one out of every 12 pregnancies. The treatment of severe traumatic brain injury in pregnancy requires a multidisciplinary team approach. The management of a pregnant trauma patient warrants consideration of several issues specific to pregnancy, such as the alterations in the maternal physiology and anatomy. In the case of maternal cardiac arrest with amniotic fluid embolism, intact neonatal survival is linked with the timing of caesarean section after maternal cardiac arrest. Moreover, the decision for perimortem caesarean section is clear after maternal cardiac arrest. The foetal survival rate is 67% if the operation is done before 15 min of cardiopulmonary compromise has occurred, and it drops to 40% at the duration range of 16–25 min. Whether minor or severe, traumatic brain injury during pregnancy is associated with unfavourable maternal outcomes. Injuries considered minor for the general population are not minor for pregnant women. Therefore, these patients should be intensively monitored, and multidisciplinary approaches should always be involved.

Patient Shielding in Diagnostic Imaging: Discontinuing a Legacy Practice

OBJECTIVE

Patient shielding is standard practice in diagnostic imaging, despite growing evidence that it provides negligible or no benefit and carries a substantial risk of increasing patient dose and compromising the diagnostic efficacy of an image. The historical rationale for patient shielding is described, and the folly of its continued use is discussed.

CONCLUSION

Although change is difficult, it is incumbent on radiologic technologists, medical physicists, and radiologists to abandon the practice of patient shielding in radiology.

Pregnancy outcome after first trimester exposure to ionizing radiations

OBJECTIVE

To evaluate the effects of ionizing radiation exposure during the first trimester of pregnancy in usual clinical situations.

STUDY DESIGN

We conducted a prospective observational cohort study using data collected between 1987 and 2014. This database was authorized by the French "Commission Nationale de l'Informatique et des Libertés". The exposed group consisted of 319 pregnant women exposed to sub diaphragmatic ionizing radiations for diagnostic purposes, during the first trimester of pregnancy, and the control group consisted of 319 pregnant women without any exposure or exposed to non-teratogenic agents. Data on maternal history and radiations exposure were collected on first contact, and pregnancy outcomes were documented at follow-up. An univariate analysis was performed to compare both groups for the main outcomes.

RESULTS

Exposure to sub diaphragmatic ionizing radiation for diagnosis purpose (median fetal dose of 3.1 mGy [0.2-130.0]) during the first trimester of pregnancy was not significantly associated with an increased risk of malformations (1.5% vs 1.8%, p = 1.00), miscarriage (7.8% vs 7.2%, p = 0.88), in utero fetal death (0.3% vs 0%, p = 1.00) or fetal growth restriction (5.4% vs 3.5%, p = 0.62).

CONCLUSION

Pregnant women exposed to irradiant diagnostic procedures do not present a higher risk of malformations, miscarriage, in utero fetal death or fetal growth restriction and should be reassured, even if the examination focused on the pelvis.

Health Impacts of Low-Dose Ionizing Radiation: Current Scientific Debates and Regulatory Issues

Health impacts of low-dose ionizing radiation are significant in important fields such as X-ray imaging, radiation therapy, nuclear power, and others. However, all existing and potential applications are currently challenged by public concerns and regulatory restrictions. We aimed to assess the validity of the linear no-threshold (LNT) model of radiation damage, which is the basis of current regulation, and to assess the justification for this regulation. We have conducted an extensive search in PubMed. Special attention has been given to papers cited in comprehensive reviews of the United States (2006) and French (2005) Academies of Sciences and in the United Nations Scientific Committee on Atomic Radiation 2016 report. Epidemiological data provide essentially no evidence for detrimental health effects below 100 mSv, and several studies suggest beneficial (hormetic) effects. Equally significant, many studies with in vitro and in animal models demonstrate that several mechanisms initiated by low-dose radiation have beneficial effects. Overall, although probably not yet proven to be untrue, LNT has certainly not been proven to be true. At this point, taking into account the high price tag (in both economic and human terms) borne by the LNT-inspired regulation, there is little doubt that the present regulatory burden should be reduced.

Radiation Risk to the Fluoroscopy Operator and Staff

OBJECTIVE

Recent articles discussing cases of brain cancer in interventionalists have raised concerns regarding the hazards of occupational exposure to ionizing radiation. We review the basics of radiation dose and the potential radiation effects, particularly as they pertain to the operator. Then we present the data regarding the risk of each type of radiation effect to the fluoroscopy operator and staff, with special attention on cancer induction, radiation-induced cataracts, and the pregnant operator.

CONCLUSION

Although the evidence overwhelmingly shows that exposure to higher doses of radiation carries a risk of cancer and tissue reactions, the risks of chronic exposure to low-level radiation are less clear. Many studies examining occupational exposure to radiation fail to show an increased risk of stochastic effects of radiation, but the positive results raise concern that the studies are underpowered to consistently detect the small risk. The lack of information in these studies about radiation doses and adherence to radiation protection further confound their interpretation. Large prospective studies of populations with occupational exposure to low-level radiation might clarify this issue. More clearly established are the risks of radiation to the fetus and the risk of cataracts in interventional cardiologists and interventional radiologists. Interventionalists can mitigate these risks by following established radiation safety practices.

Limiting foetal doses during a four-vessel angiogram and endovascular stent-assisted berry aneurysm repair: A case report

A 36-year-old female patient, 20 weeks pregnant, was diagnosed with a left internal carotid artery aneurysm. Fluoroscopically guided repair was justified. A four-vessel cerebral angiogram was performed, and a left paraclinoid aneurysm was demonstrated. The patient subsequently underwent endovascular stent-assisted berry aneurysm repair. As the patient was pregnant, the procedure was preceded by consideration of the required radiation protection. The foetal dose was estimated as negligible. Active management of foetal exposures may improve radiation protection during pregnancy.

Multiple meningiomas in a woman irradiated in utero

Meningiomas are a common central nervous system tumour and radiation is a known risk factor for their development. In utero radiation exposure correlates to developmental abnormalities and carcinogenesis in a dose- and gestational age-related manner. Radiation induced meningioma has been reported in detail in the literature in patients who had been irradiated earlier in life. At the time of publication, there was no data on radiation exposure whilst in utero and meningioma. We report on a 42-year-old woman with multiple intracranial meningiomas and no other risk factors except a history of in utero exposure to low dose X-ray radiation at 12weeks gestational age.