MR Imaging of Maternal Diseases of the Abdomen and Pelvis during Pregnancy and the Immediate Postpartum Period

Navigating the Complexities of Symptomatic Hydronephrosis in Pregnancy

The management of symptomatic hydronephrosis presents substantial challenges due to the absence of consensus within clinical guidelines concerning pain management, diagnostic approaches, therapeutic interventions, and follow-up protocols. This literature review focuses on complexities involving diagnostic challenges that arise from the difficulty in distinguishing physiological from pathological obstruction and treatment complexities that involve deciding on the most appropriate pain management medications and safe interventions while minimizing risks to both the mother and foetus. To address these challenges, a comprehensive search of electronic databases, including PubMed, Embase, and Google Scholar, was conducted for the terms "hydronephrosis", "hydronephrosis in pregnancy", "ionising radiation in pregnancy", and "safe analgesia in pregnancy". Moreover, Mendeley software was used to collect and organize the references. Diagnostic complexities involve selecting the appropriate imaging modality that balances accurate diagnosis with minimal radiation to the foetus. Ultrasound remains the first-line option. However, it has limitations in delineating the underlying aetiology. MRI avoids ionizing radiation but has restricted utility due to foetal movement artifacts. CT provides the highest diagnostic accuracy but raises foetal radiation exposure concerns, though ultra-low dose protocols (<1 mGy) are deemed acceptable by most guidelines. Management includes either a conservative approach, which is a safe option in the majority of cases, or intervention with a percutaneous nephrostomy or ureteric stent insertion, both with comparable symptom control. However, there is no consensus on the optimal frequency for drain changes to prevent rapid encrustation. Definitive procedures like ureteroscopy and percutaneous nephrolithotomies remain controversial. Most guidelines suggest limiting these interventions to specialist centres during the second trimester if required.

Cervical cancer in the pregnant population

Cervical cancer is the second most encountered cancer in pregnant patients. The 2018 International Federation of Gynecology and Obstetrics (FIGO) staging system for cervical cancer updated the staging of primary cervical carcinoma and disease process, with formal incorporation of imaging as a vital source of information in the management process to improve accuracy. Diagnosis and treatment of the pregnant population is a complex interplay of achieving adequate diagnostic information and optimal treatment while minimizing toxicity and risks to the mother and fetus. While novel imaging techniques and anticancer therapies are rapidly developed, much information on the safety and feasibility of different therapies is not yet available in the pregnant population. Therefore, managing pregnant patients with cervical cancer is complex and requires a multidisciplinary approach.

Acute Ischemic Stroke in Pregnancy : A Practical Focus on Neuroimaging and Reperfusion Therapy

INTRODUCTION

Pregnancy increases the risk of acute ischemic stroke (AIS) among young women and is responsible for about 5% of maternal deaths and significant disability. Concerns of potential adverse events of imaging and reperfusion therapies in this group of patients can lead to a substantial delay or omission of treatment that can significantly worsen outcomes.

OBJECTIVE

The objective of this study is to discuss main concerns of diagnosis and therapy of pregnant patients with AIS regarding neuroimaging and reperfusion treatment.

RESULTS

The cumulative radiation dose of computed tomography (CT)-based entire diagnostic procedure (noncontrast CT, CT-angiography and CT-perfusion) is estimated to be below threshold for serious fetal radiation exposure adverse events. Similarly, magnetic resonance imaging(MRI)-based imaging is thought to be safe as long as gadolinium contrast media are avoided. The added risk of intravenous thrombolysis (IVT) and mechanical thrombectomy during pregnancy is thought to be very low. Nevertheless, some additional safety measures should be utilized to reduce the risk of radiation, contrast media and hypotension exposure during diagnostic procedures or reperfusion treatment.

CONCLUSION

Fetal safety concerns should not preclude routine diagnostic work-up (except for gadolinium contrast media administration) in childbearing AIS women, including procedures applied in unknown onset and late onset individuals. Due to rather low added risk of serious treatment complications, pregnancy should not be a sole contraindication for neither IVT, nor endovascular treatment.

Multisystem Imaging Recommendations/Guidelines: In the Pursuit of Precision Oncology

With an increasing rate of cancers in almost all age groups and advanced screening techniques leading to an early diagnosis and longer longevity of patients with cancers, it is of utmost importance that radiologists assigned with cancer imaging should be prepared to deal with specific expected and unexpected circumstances that may arise during the lifetime of these patients. Tailored integration of preventive and curative interventions with current health plans and global escalation of efforts for timely diagnosis of cancers will pave the path for a cancer-free world. The commonly encountered circumstances in the current era, complicating cancer imaging, include coronavirus disease 2019 infection, pregnancy and lactation, immunocompromised states, bone marrow transplant, and screening of cancers in the relevant population. In this article, we discuss the imaging recommendations pertaining to cancer screening and diagnosis in the aforementioned clinical circumstances.

Diffusion-weighted imaging versus non-contrast magnetic resonance imaging in the diagnosis of acute appendicitis during pregnancy

OBJECTIVE

The aim of this study was to evaluate the diagnostic performance of diffusion-weighted imaging compared to non-contrast magnetic resonance imaging in the differential diagnosis of acute appendicitis in pregnant patients.

METHODS

A total of 72 pregnant patients with the suspicion of acute appendicitis who underwent magnetic resonance imaging combined with diffusion-weighted imaging examinations were enrolled in this retrospective study. Magnetic resonance imaging images (non-contrast and diffusion-weighted imaging sequences) were evaluated. Moreover, apparent diffusion coefficient ratios were estimated. The diagnostic performances of magnetic resonance imaging and diffusion-weighted imaging findings were statistically analyzed on the basis of surgical and follow-up results.

RESULTS

Of 72 pregnant patients, 10 (14%) had acute appendicitis on magnetic resonance imaging and diffusion-weighted imaging. Among 10 patients with acute appendicitis, three (3/10) had perforation. diffusion-weighted imaging findings had higher sensitivity (90 versus 60%), negative predictive value (98.41 versus 93.94%), and accuracy (98.61 versus 94.44%) ratios compared to non-contrast magnetic resonance imaging in the diagnosis of acute appendicitis. There was one false-negative result on diffusion-weighted imaging. Diffusion restriction facilitated the detection of appendicitis. The apparent diffusion coefficient ratios were lower in acute appendicitis than in the normal appendix (0.70±0.19 versus 0.96±0.16) (p<0.05).

CONCLUSION

With a shorter scan time and higher diagnostic accuracy, diffusion-weighted imaging can be useful for the early diagnosis of acute appendicitis and for planning appropriate management.

Pregnancy in a rudimentary horn: multicenter's MRI features of a rare condition

PURPOSE

To describe the MRI features of rudimentary horn pregnancy (RHP) with surgical correlations.

METHODS

Nine women with a RHP underwent preoperative pelvic MRI. MRI protocol included T2- (n = 9), T1- (n = 7), and fat-suppressed contrast-enhanced T1-weighted sequences (n = 4). Two pelvic radiologists retrospectively analyzed MR images to assess the following MRI features: presence of a myometrium around the gestational sac (GS) and characteristics of its wall, GS surrounded by myometrium in contact with the round ligament, communication of the GS with the endometrial cavity of the main horn, continuity of the GS with the cervix, fibrous or muscular GS attachment to the main horn, lateral deviation, and endometrial thickness of the main horn. Ovaries and tubes were also assessed. MRI features were correlated with surgical findings.

RESULTS

Seven of the nine women [29 ± 6 SD years (range 16-37 years)] underwent surgical management. The first US diagnosed RHP in only 1/9 patients. All pregnancies were diagnosed using MRI. RHP was all located in the rudimentary horn of a unicornuate uterus. All the GS was surrounded by myometrium in contact with the round ligament. None of the RHP displayed communication with the endometrial cavity of the main horn nor with the cervix. An attachment between the RHP and the main horn was seen in 3/9 patients. All the main horns were lateralized and empty.

CONCLUSION

MRI diagnosed RHP in all patients by identifying the GS surrounded by myometrium in contact with the round ligament and the absence of continuity between the GS and the cervix.

LEVEL OF EVIDENCE

IV-retrospective study.

Operative management of acute abdomen after bariatric surgery in the emergency setting: the OBA guidelines

BACKGROUND

Patients presenting with acute abdominal pain that occurs after months or years following bariatric surgery may present for assessment and management in the local emergency units. Due to the large variety of surgical bariatric techniques, emergency surgeons have to be aware of the main functional outcomes and long-term surgical complications following the most performed bariatric surgical procedures. The purpose of these evidence-based guidelines is to present a consensus position from members of the WSES in collaboration with IFSO bariatric experienced surgeons, on the management of acute abdomen after bariatric surgery focusing on long-term complications in patients who have undergone laparoscopic sleeve gastrectomy and laparoscopic Roux-en-Y gastric bypass.

METHOD

A working group of experienced general, acute care, and bariatric surgeons was created to carry out a systematic review of the literature following the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) and to answer the PICO questions formulated after the Operative management in bariatric acute abdomen survey. The literature search was limited to late/long-term complications following laparoscopic sleeve gastrectomy and laparoscopic Roux-en-Y gastric bypass.

CONCLUSIONS

The acute abdomen after bariatric surgery is a common cause of admission in emergency departments. Knowledge of the most common late/long-term complications (> 4 weeks after surgical procedure) following sleeve gastrectomy and Roux-en-Y gastric bypass and their anatomy leads to a focused management in the emergency setting with good outcomes and decreased morbidity and mortality rates. A close collaboration between emergency surgeons, radiologists, endoscopists, and anesthesiologists is mandatory in the management of this group of patients in the emergency setting.

Magnetic Resonance Imaging of Acute Abdominal Pain in the Pregnant Patient

Evaluation of a pregnant patient presenting with acute abdominal pain can be challenging to accurately diagnose for a variety of reasons, and particularly late in pregnancy. Noncontrast MR remains a safe and accurate diagnostic imaging modality for the pregnant patient presenting with acute abdominal pain, following often an initially inconclusive ultrasound examination, and can be used in most settings to avoid the ionizing radiation exposure of a computed tomography scan. Pathologic processes discussed in this article include some of the more common gastrointestinal, hepatobiliary, genitourinary, and gynecologic causes of abdominal pain occurring in pregnancy, as well as traumatic injuries.

Kidney morphology in pregnancy using T2-weighted MRI

AIM

To report the morphology of maternal kidneys captured on fetal magnetic resonance imaging (MRI) including kidney length, volume, renal pelvis diameter, and corticomedullary differentiation in pregnancy.

MATERIALS AND METHODS

A retrospective study of maternal kidney morphology captured incidentally on fetal MRI. Women without chronic kidney disease, with a complete view of both kidneys and a singleton pregnancy were included. Kidney length, maximal renal pelvis diameter, kidney volume, and corticomedullary differentiation ratio were measured independently in duplicate. Associations with maternal and pregnancy variables were explored using linear regression.

RESULTS

MRI images from 42 women were performed at 22-32 weeks' gestation. Serum creatinine concentrations are not checked routinely during pregnancy and were available for 15 (36%) women, with a median creatinine of 57 μmol/l (IQR: 50-63 μmol/l). Mean interpolar lengths were 10.9 and 10.4 cm for the left and right kidneys and varied with height. Mean maximal renal pelvis diameters were 9 mm and 12 mm, with upper reference intervals of 17 and 25 mm for the left and right kidneys, respectively. Renal volume in pregnancy was within the non-pregnant reference interval and varied with height and gestation.

CONCLUSIONS

Maternal kidney length and volume in pregnancy are within the normal reference intervals for non-pregnant women. Renal pelvis diameter in pregnancy measured using MRI is substantially higher than described previously by ultrasound, with implications for routine reporting.

Progress in research of acute pancreatitis in pregnancy

Acute pancreatitis in pregnancy (APIP) is a rare and severe complication of pregnancy, which is characterized by rapid onset, rapid progression, many complications, and high mortality. According to previous studies, the incidence of APIP is about 1/10000-1/1000 and increases with gestational age. Due to the differences in genetic background and dietary habits between Asian and European populations, the incidence of APIP in China is as high as 1.14‰-2.27‰, significantly higher than that in Western countries. The lack of specific clinical symptoms of APIP often leads to misdiagnosis or missed diagnosis, which greatly increases the difficulty of diagnosis and treatment. Despite the deepening of the research on APIP, its pathogenesis is still unclear. This paper will give a systematical review of APIP.

Postpartum hemorrhage - what the interventional radiologist should know

Postpartum hemorrhage is a leading cause of maternal morbidity and mortality around the world and can be caused by multiple etiologies. Distinguishing between the various etiologies that lead to PPH and identifying high risk features are crucial to implementing effective clinical management. In this review, the diagnostic imaging features and management principles of some of the most important causes of postpartum hemorrhage are discussed, with an emphasis on the pearls and pitfalls when minimally invasive treatment via interventional radiologic techniques are employed.

Investigation of Effects of Gadolinium-Based Contrast Agents on Uterine Contractility Using Isolated Rat Myometrium

BACKGROUND

Despite concerns about safety, gadolinium-based contrast agents (GBCAs) are still used for abdominal and pelvic imaging during pregnancy. Researchers have mainly focused on teratogenicity, while very little is known about their possible direct effects on uterine contractility, yet free gadolinium potentially impacts contractility through interaction with calcium channels.

PURPOSE

To investigate possible effects of selected GBCAs (namely gadoteridol, gadoversetamide, gadobutrol, gadoterate meglumine, and gadoxetic acid) on the contractility of rat myometrium.

STUDY TYPE

In vitro organ bath study.

ANIMAL MODEL

Myometria were isolated from adult (10-12 weeks old) Sprague Dawley rats, both pregnant (N = 8) and nonpregnant (N = 36).

FIELD STRENGTH/SEQUENCE

NA.

ASSESSMENT

Myometrial strips were suspended in tissue bath containing physiological saline and isometric contractions were recorded. GBCAs were added to the tissue bath cumulatively, and their effects on contractility parameters (quantified by amplitude, frequency, and area under contractility curve [AUC]) were evaluated by 10-minute intervals.

STATISTICAL TESTS

Normality data, checked by Shapiro-Wilk test, were transformed by arcsine when needed. One- or two-way analysis of variance was performed, where appropriate, followed by Student-Newman-Keuls test. A P value of <0.05 was considered statistically significant.

RESULTS

All of the assayed GBCAs elicited some alterations in the myometrial contractility in a concentration-dependent manner. Gadoterate meglumine, gadoxetic acid, and gadoversetamide caused a concentration-dependent significant attenuation in AUC (oxytocin-induced, from 100% during control period to 45.1 ± 9.0% (nonpregnant) and 59.9 ± 8.5% (pregnant), for 90 μM gadoterate meglumine; respectively), and frequency of the spontaneous and oxytocin-induced contractions. Gadobutrol and gadoteridol at highest dose significantly attenuated mean AUC and frequency of oxytocin-induced contractions of nonpregnant myometrium.

DATA CONCLUSION

Results from this in vitro study indicate that GBCAs elicit modulation of myometrial contractions at clinically relevant concentrations. These effects may account, at least partially, for the known potential side effects (rare cases of miscarriages and elective abortion) of these agents.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 5.

CT and MRI Evaluations in Crohn's Complications: A Guide for the Radiologist

Inflammatory bowel diseases (IBD) are a group of chronic inflammatory intestinal conditions with unknown etiology. Crohn's disease (CD) and ulcerative colitis (UC) are the two main types of IBD and they have some interchangeable and some different clinical and pathological characteristics. When diagnosis is performed for the first time, the majority of CD patients have a predominant inflammatory condition. As the disease progresses most patients experience the development of complications, such as abscesses, fistulas, perforation, strictures, and others. Both computed tomography (CT) and Magnetic Resonance Imaging (MRI) allow great view of the whole length of the intestinal tract together with the eventual extra-and intra-intestinal complications. MR enterography (MRE) and CT enterography (CTE), performed after oral administrations of contrast medium, have similar diagnostic accuracy for the diagnosis of CD and its complications. Even though CT is still the most familiar diagnostic technique used for studying CD worldwide, MRE have several important benefits that are leading to rapid increase in its employment in the last years. In particular, MRE allows a superior soft tissue contrast resolution compared to CT, offering a better visualization of bowel wall and its inflammatory and fibrotic characteristics. Moreover, Pelvic Magnetic Resonance is the principal technique in patients with perianal disease due to its ability of providing precise and fine detail images of the sphincter complex, which are crucial for evaluating pelvic disease. In this paper we describe common and uncommon complications in patients with CD, and explain how to identify their findings in CT and MR exams.

Multidisciplinary Management of Cancer During Pregnancy

Cancer during pregnancy is relatively rare but is increasing in frequency in countries in which the maternal child-bearing age continues to rise. The complexities of medical decision making are underscored by the need to weigh the potential benefits of any intervention for the mother against the risks to the fetus. A majority of diagnostic evaluations can be performed safely in the setting of pregnancy and should not be delayed. Noninvasive prenatal testing that shows discordance with fetal karyotype can be a clue to an underlying maternal malignancy. After diagnosis, a multidisciplinary team should formulate a care plan for both the mother and the fetus. Key topics for discussion should include the mother's prognosis, standard treatment plan, and predictions of how modifications for a continuing pregnancy will affect the treatment plan and overall prognosis. In the context of this knowledge, frank discussions about pregnancy termination should be addressed with the patient, if appropriate. Selection of a plan for oncologic management in the case of a pregnant woman is based on the type of cancer, the tumor biology, and the tumor stage. Additional complexities for pregnant patients are typically related to the gestational age of the fetus, the dynamic physiologic changes of pregnancy, and the limited safety data for administration of most anticancer therapies during pregnancy. In this article, we summarize data related to different classes of anticancer therapies as well as considerations for the management of selected cancers. Finally, we provide some key principles that should be considered in the management of patients with cancer during pregnancy.

Imaging during pregnancy: What the radiologist needs to know

During the last decades, there has been a growing demand for medical imaging in gravid women. Imaging of the pregnant woman is challenging as it involves both the mother and the fetus and, consequently, several medical, ethical, or legal considerations are likely to be raised. Theoretically, all currently available imaging modalities may be used for the evaluation of the pregnant woman; however, in practice, confusion regarding the safety of the fetus often results in unnecessary avoidance of useful diagnostic tests, especially those involving ionizing radiation. This review article is focused on the current safety guidelines and considerations regarding the use of different imaging modalities in the pregnant population; also presented is an imaging work-up for the most common medical conditions of pregnant women, with emphasis on fetal and maternal safety.

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.

Applicability of ultrasonography for detection of marginal sinus placenta previa

This study aimed to examine whether marginal sinus placenta previa, defined as when the marginal sinus just reaches the internal cervical os and placental parenchyma might be >2 cm from the internal cervical os, can be diagnosed using ultrasonography (US). We identified the placenta previa cases that underwent both US and magnetic resonance imaging (MRI) between April 2010 and December 2018 at our institution. The diagnostic discrepancies for marginal sinus placenta previa between US and MRI were examined retrospectively. Of the 183 cases of placenta previa, 28 (15.3%) cases were diagnosed as marginal sinus placenta previa using MRI. Among them, 18 cases (64.3%) could also be diagnosed using US. The sensitivity and specificity of the diagnosis of marginal sinus placenta previa using US were 64.3% and 92.9%, respectively. A change in US diagnosis occurred in 10 (35.7%) cases, all of which were diagnosed with low-lying placenta previa or marginal placenta previa and did not develop any serious miserable obstetrical outcomes. In conclusion, the diagnostic accuracy of US for detecting marginal sinus placenta previa was not significant. MRI examination may be required to accurately categorize the types of placenta previa.

Dyslipemias and pregnancy, an update

During pregnancy there is a physiological increase in total cholesterol (TC) and triglycerides (TG) plasma concentrations, due to increased insulin resistance, oestrogens, progesterone, and placental lactogen, although their reference values are not exactly known, TG levels can increase up to 300mg/dL, and TC can go as high as 350mg/dL. When the cholesterol concentration exceeds the 95^th percentile (familial hypercholesterolaemia (FH) and transient maternal hypercholesterolaemia), there is a predisposition to oxidative stress in foetal vessels, exposing the newborn to a greater fatty streaks formation and a higher risk of atherosclerosis. However, the current treatment of pregnant women with hyperlipidaemia consists of a diet and suspension of lipid-lowering drugs. The most prevalent maternal hypertriglyceridaemia (HTG) is due to secondary causes, like diabetes, obesity, drugs, etc. The case of severe HTG due to genetic causes is less prevalent, and can be a higher risk of maternal-foetal complications, such as, acute pancreatitis (AP), pre-eclampsia, preterm labour, and gestational diabetes. Severe HTG-AP is a rare but potentially lethal pregnancy complication, for the mother and the foetus, usually occurs during the third trimester or in the immediate postpartum period, and there are no specific protocols for its diagnosis and treatment. In conclusion, it is crucial that dyslipidaemia during pregnancy must be carefully evaluated, not just because of the acute complications, but also because of the future cardiovascular morbidity and mortality of the newborn child. That is why the establishment of consensus protocols or guidelines is essential for its management.

[The (severely) injured pregnant patient from the perspective of radiology]

Trauma is one of the leading causes of mortality in pregnant women and significantly increases the likelihood of an unwanted termination of pregnancy. Particularly in severe trauma with an increased risk of significant maternal injuries, computed tomography (CT) remains the imaging modality of choice as it is comprehensively available, quick to carry out and has a high diagnostic accuracy in the detection and classification of life-threatening trauma-associated pathologies compared to other imaging techniques. Considering the radiation-associated risks, it is unlikely that a single, monophasic CT in the emergency trauma room will exceed the threshold of deterministic radiation damage; therefore, fetal malformations or fetal loss are not to be expected; however, there is a low stochastic risk for the delayed occurrence of radiation-induced cancer both for the child and the mother that can be considered small in comparison to missed or delayed diagnoses after severe trauma. Intravenous, nonionic iodinated contrast agents are not contraindicated during pregnancy and should be administered whenever their use would also be considered appropriate in a nonpregnant patient; however, unnecessary scans and, if possible, multiple contrast agent phases should be avoided in order to reduce radiation. Magnetic resonance imaging (MRI) has a major role in the subacute setting and constitutes an excellent problem solver for specific questions, such as the evaluation of discoligamentous injuries of the spine. Its use is deemed acceptable at any stage of pregnancy when the required information is considered important for the management of further treatment. Due to potential teratogenic effects of MRI contrast media containing gadolinium on the fetus, including an increased likelihood of fetal loss, they should only be administered with great caution and under strictly defined indications.

ACR Appropriateness Criteria® Postpartum Hemorrhage

Postpartum hemorrhage (PPH) can be categorized as primary or early if occurring in the first 24 hours after delivery, whereas late or delayed PPH occurs between 24 hours and 6 weeks. Most of the causes of PPH can be diagnosed clinically, but imaging plays an important role in the diagnosis of many causes of PPH. Pelvic ultrasound (transabdominal and transvaginal with Doppler) is the imaging modality of choice for the initial evaluation of PPH. Contrast-enhanced CT of the abdomen and pelvis and CT angiogram of the abdomen and pelvis may be appropriate to determine if active ongoing hemorrhage is present, to localize the bleeding, and to identify the source of bleeding. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Bowel obstruction due to the tightening of a loose bowel adhesion with uterus enlargement during pregnancy

Introduction. Acute intestinal obstruction during pregnancy is a rare digestive surgical emergency. Generally, it is associated with significant maternal and fetal mortality. The diagnosis is difficult, often delaying the therapeutic management. It is reported an exceptional association of acute intestinal obstruction due to a band adhesion that is put into tension as the uterus enlarges. Case Report. A 35 years old Caucasian pregnant woman with a past medical history of appendectomy was examined and found with abdominal pain, severe vomiting, and bowel obstruction. The patient underwent surgery. Per operatively, the obstruction was caused by an adhesion put into tension by the enlargement of the uterus. The postoperative course was uneventful and the patient was discharged on day 2. Conclusions. The etiological diagnosis of acute intestinal obstruction during pregnancy is difficult. Surgery is the cornerstone of the treatment and the management varies depending on the intraoperative findings and the condition of the patient.

Vólvulo del ciego, una entidad infrecuente como causa de abdomen agudo en embarazadas: Reporte de caso clínico y revisión de la literatura

Introducción. El vólvulo cecal en el embarazo es una patología infrecuente a nivel mundial, con un espectro clínico variado y limitación en estudios diagnósticos, lo que puede resultar en un desenlace ominoso. Caso clínico. Se presenta el caso de una gestante en segundo trimestre del embarazo quien presenta abdomen agudo secundario a vólvulo cecal y sufrimiento fetal. La paciente fue llevada a cesárea de urgencia, donde además se practicó cecectomía y anastomosis íleo transversa, con mortalidad fetal. Discusión. El vólvulo cecal forma parte de los diagnósticos diferenciales en caso de abdomen agudo durante el embarazo. Tiene un pronóstico reservado, en donde pueden presentarse desenlaces maternos y perinatales adversos, con mortalidad maternofetal.

Placenta percreta evaluated by MRI: correlation with maternal morbidity

PURPOSE

The purpose of this study was to evaluate the capability of MRI in depicting the topography of placenta percreta (PP) and to further explore the correlation between invasion topography and maternal outcomes.

METHODS

55 patients with histologically or surgically confirmed PP were included in this retrospective study. Two senior radiologists evaluated the topography of PP based on MR images: the invasion topography was depicted as S1, S2, parametrial, bladder, and cervical invasion. The correlation between invasion topography and maternal outcomes was analyzed using Chi-square statistic.

RESULTS

MRI showed high sensitivity and specificity in delineating the invasion topography of PP (ranging from 87.5 to 100%). MRI had 100% specificity for predicting the parametrial, bladder, and cervical invasion. The rate of cesarean hysterectomy, ureteral injuries and ICU administration, and the amount of blood transfusions in PP with S2 invasion were higher than S1 invasion (P < 0.05). In addition, all patients with bladder invasion (8/8) received partial bladder resection by urologists. All the patients with S2 parametrial invasion (12/12) or cervical invasion (9/9) underwent cesarean hysterectomy.

CONCLUSION

MRI was capable in predicting the invasion topography of PP patients. Moreover, PP patients with S2, parametrial, bladder or cervical invasion had more severe maternal morbidity.

MRI of Acute Gynecologic Conditions

Although usually not a first-line imaging modality in the setting of acute pelvic pain, magnetic resonance imaging (MRI) is able to depict and characterize a wide range gynecologic diagnoses with high accuracy. Lack of ionizing radiation renders MRI particularly useful for assessment of pregnant women and children. Furthermore, inherent high soft-tissue resolution of MRI allows accurate diagnosis without intravenous contrast use, which is advantageous for patients with renal insufficiency and pregnant patients. Familiarity with the typical MRI appearance of various acute gynecologic conditions helps establish the correct diagnosis. This article reviews the common MRI findings of acute gynecologic processes, in both pregnant and nonpregnant patients. Level of Evidence: 3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;51:1291-1309.

MRI evaluation of the placenta from normal variants to abnormalities of implantation and malignancies

Even though the placenta has been known for millennia, it is still considered one of the most complex and least understood human organs. Imaging of the placenta is gaining attention due to its impact on fetal and maternal outcomes. MRI plays a vital role in evaluation of inconclusive cases by ultrasonography. It enables precise mapping of placental abnormalities for proper multidisciplinary planning and management. In this article we provide a comprehensive in-depth review of the role of antenatal MR in evaluating "The Placenta." We will describe the protocols and techniques used for MRI of the placenta, review anatomy of the placenta, describe MRI features of major placental abnormalities including those related to position, depth of implantation, hemorrhage, gestational trophoblastic neoplasia, and retained products of conception and discuss the added value of MRI in the management and preoperative planning of such abnormalities. Level of Evidence: 3 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2019;50:1702-1717.

Use of Magnetic Resonance Imaging in Evaluating Fetal Brain and Abdomen Malformations during Pregnancy

Magnetic resonance imaging (MRI) is used as a clarifying technique after a high-resolution ultrasound examination during pregnancy. Combining ultrasound with MRI, additional diagnostic information is obtained or ultrasound diagnosis is frequently corrected. High spatial resolution provides accurate radiological imaging of internal organs and widens possibilities for detecting perinatal development disorders. The safety of MRI and the use of intravenous contrast agent gadolinium are discussed in this article. There is no currently available evidence that MRI is harmful to the fetus, although not enough research has been carried out to prove enduring safety. MRI should be performed when the benefit outweighs the potential side effects. The narrative review includes several clinical cases of fetal MRI performed in Vilnius University Hospital Santaros Clinics.

Radiologic Aspects of the Diagnosis of Pulmonary Embolism in Pregnancy

Pulmonary embolism in pregnancy is a leading cause of maternal mortality. The clinical presentation is often nonspecific, making imaging essential for accurate diagnosis. After reviewing the literature on the radiologic diagnosis of pulmonary embolism in pregnancy, we concluded that both computed tomography pulmonary angiography and lung perfusion scintigraphy are sensitive with high positive predictive values in the presence of high clinical suspicion, but lung perfusion scintigraphy is recommended given lower maternal breast exposure to ionizing radiation and lower fetal contrast exposure. However, if a chest x-ray is abnormal, computed tomography pulmonary angiography is preferred due to high nondiagnostic rates of lung perfusion scintigraphy.

MRI in pregnancy: Indications and practical considerations

There is a constantly evolving knowledgebase regarding the safety of MRI in pregnant patients, as well as the safety of gadolinium administration, given potential fetal risks. This review provides an overview of national and international recommendations for patient screening and safety by trimester, evaluates the most recent literature regarding administration of gadolinium in pregnant patients, and discusses technical requirements when imaging pregnant patients. A protocol for imaging pregnant patients is provided, and multiple common indications for MRI in pregnancy are discussed. Level of Evidence 5. Technical Efficacy Stage 5. J. Magn. Reson. Imaging 2019;49:621-631.

A survey of pediatric diagnostic radiologists in North America: current practices in fetal magnetic resonance imaging

BACKGROUND

Fetal magnetic resonance imaging (MRI) is an imaging examination in evolution. Rapid developments over recent decades have led to better image quality, an increased number of examinations and greater impact on patient care.

OBJECTIVE

To gather data regarding current practices among established programs in North America and provide information to radiologists interested in implementing or growing a fetal MRI service.

MATERIALS AND METHODS

An electronic survey containing 15 questions relevant to the use of fetal MRI was submitted to pediatric radiologists and neuroradiologists. Items regarded scheduling and reporting logistics, magnet strength, patient positioning and patient preparation. Answers and comments were collected, and descriptive statistics were summarized.

RESULTS

One hundred and six survey responses were evaluated. Of the survey responses, 62/106 (58.5%) allow fetal MR scheduling any time during the day and 72/105 (68.6%) exclusively use 1.5-T strength platforms for fetal MRI, while only 7/105 (6.7%) use exclusively 3 T. Patient positioning is variable: supine, 40/106 (37.8%); left lateral decubitus, 22/106 (20.8%), and, patient's choice, 43/106 (40.6%). Of the centers responding, 51/104 (49.0%) require no particular fasting instructions, while 20/104 (19.2%) request the patient avoid caffeine before the scanning.

CONCLUSION

Logistical trends in performing fetal MRI may supplement the American College of Radiology's published technical standards and offer guidance to radiologists new to the field.

Use of Postpartum Magnetic Resonance Imaging for Diagnosis and Classification of Retained Placenta Tissue

OBJECTIVE

To study the potential application of magnetic resonance imaging (MRI) for classification of retained placental tissue (RPT) in the uterus postnatally.

METHODS

Twenty-two patients with clinically or pathologically proven RPT were studied.

RESULTS

The thickness ratio (D1/D2) of invaded (D1) to normal (D2) myometrium could be categorized into 3 groups (>0.6, 0.1-0.6, and <0.1) correlating with the 3 types of RPT: accreta vera (RPA), increta (RPI), and percreta (RPP) (r = -0.861, P < 0.01). After uterine arterial embolization, the RPT showed lower signal intensity than the myometrium without flow voids on T2-weighted images. Two cases of RPP showed gradual enhancement, except 1 case of infection and 2 cases that did not involve enhancement examinations, whereas 17 cases of RPA and RPI showed early enhancement.

CONCLUSIONS

Magnetic resonance imaging can facilitate diagnosis of RPT severity. Dynamic contrast enhancement can indicate RPT activity and blood supply, thereby ensuring appropriate clinical decision making.

Persistent methicillin-resistant Staphylococcus aureus bacteremia owing to placental abscess

Staphylococcus aureus as a pathogen in human gestational membranes, a rather rare phenomenon, has recently been the focus of several researches. S. aureus forms biofilms on these membranes and potentially causes chorioamnionitis in pregnant women. We report a case of persistent methicillin-resistant S. aureus (MRSA) bacteremia owing to placental infection, causing chorioamnionitis and preterm birth. A 29-year-old Japanese woman at the 27th gestational week was diagnosed with acute promyelocytic leukemia and underwent all-trans retinoic acid therapy. Soon after hospitalization, the patient presented with persistent MRSA bacteremia of unknown origin. Despite various antimicrobial therapies, she experienced 12 MRSA bacteremia episodes over 6 weeks. However, after child birth, MRSA bacteremia disappeared without any complications. A pathologic examination of her placenta revealed placenta abscess, resulting in a diagnosis of MRSA-associated chorioamnionitis. Molecular analysis proved that a single MRSA strain (SCCmec Type IVa), which tested negative for Panton-Valentine leukocidin and toxic shock syndrome toxin-1, caused the obstinate infection. We should be aware that persistent MRSA bacteremia in pregnant women can originate from placental abscess.

What may cause fetus loss from acute pancreatitis in pregnancy: Analysis of 54 cases

Acute pancreatitis in pregnancy (APIP) poses a serious threat to the mother and her fetus, and might lead to fetal loss including miscarriage and stillbirth in certain patients. We sought to identify possible factors that affect fetal distress and evaluated outcomes of patients with APIP.We retrospectively reviewed clinical records of 54 pregnant women with APIP, who were treated at 2 tertiary clinical centers over a 6-year period. Clinical characteristics including etiology and severity of APIP, fetal monitoring data, and maternofetal outcomes were analyzed.Etiology of APIP included acute biliary pancreatitis (ABP, n = 14), hyperlipidemic pancreatitis (HLP, n = 22), and other etiologies (n = 18). Severity was classified as mild acute pancreatitis (MAP, n = 23), moderately severe acute pancreatitis (MSAP, n = 24), and severe acute pancreatitis (SAP, n = 7). The incidence of preterm delivery, fetal distress, and fetal loss increased with the progression of severity of APIP (P < .05). The severity of HLP was significantly higher than that of ABP and APIP of other etiology (P < .01). HLP was more likely to lead to fetal distress than other APs (P < .01). Only 12 (22.2%) patients had fetal monitoring including non-stress test (NST); 1 case of SAP (14.3%) and 15 cases of MSAP (62.5%) were not transferred to intensive care unit for intensive monitoring.The incidence of fetal distress and fetal loss increased with worsening of APIP severity. HLP tends to result in worse fetal outcomes. The deficiencies of fetal state monitoring, lack of assessment, and management of pregnant women might increase the fetal loss in APIP.

[Physiological hydronephrosis in pregnancy: Occurrence and possible causes. An MRI study]

INTRODUCTION

The etiology of the uretero-hydronephrosis in pregnancy is just hypothesis: hormonal or mechanical hypothesis, only investigated by echographic studies. MRI permits to visualize the entirety of the urinary tract, which can be helpful to find out a mechanical cause.

METHODOLOGY

We have analysed the MRI of 100 asymptomatic pregnant women. We have determined the number and locations of the uretero-hydronephroses and researched whether there is any relationship between the uretero-hydronephrosis and certain abdominal structures. We focused on the psoas muscle and measured its depth, width and calculated its surface by a reproducible method.

RESULTS

The analysis revealed that the uretero-hydronephrosis was predominantly at the right side (63%) and in the majority of the cases limited to the kidney (42%) and/or the proximal third of the ureter (42%). We were able to rule out some proposed etiologies: a compression of the ureter between the uterus and the iliac or ovarian vessels; a protective effect of the left intestinal structures. A link was observed between the psoas muscle and the physiological uretero-hydronephrosis: the ipsilateral psoas muscle seemed smaller in pregnant women presenting a uretero-hydronephrosis.

CONCLUSION

We have highlighted a link between a physiological uretero-hydronephrosis during pregnancy and a lesser developped psoas muscle. The hypothesis proposed is that a smaller psoas muscle would have a less protective effect of the ureter due to a lesser development. This study offers a practical conclusion: a left sided uretero-hydronephrosis during pregnancy and/or including the entirety of the ureter is more probably a pathological hydronephrosis.

LEVEL OF EVIDENCE

4.

Imaging in the post-partum period: clinical challenges, normal findings, and common imaging pitfalls

Complex physiological and biochemical changes occur in women during the post-partum period, many of which are incompletely understood. There are limited descriptions within the medical literature about expected imaging findings during this period and this review aims to illustrate 'normal' appearances following vaginal delivery and Cesarean section. We will also discuss some of the pertinent clinical challenges and imaging pitfalls encountered in assessing the post-partum female.

Diagnostic Imaging of Pregnant Women - The Role of Magnetic Resonance Imaging

BACKGROUND

Presentation of magnetic resonance imaging (MRI) findings in pregnant women in the Department of Diagnostic Imaging, Institute of Mother and Child, Warsaw, Poland.

MATERIAL/METHODS

Forty-three symptomatic pregnant women underwent MRI between 9 and 33 weeks of gestation (mean of 23 weeks). Moreover, we included 2 pregnant women who underwent fetal MRI and had incidental abnormalities.

RESULTS

In 9 cases, we excluded the suspected brain abnormalities. In 4 cases, we found unremarkable changes in the brain without clinical significance. One patient was diagnosed with multiple sclerosis, one with cortical dysplasia, one with pineal hemorrhage and one with a brain tumor. On abdominal MRI, 2 patients had normal findings, one patient had colon cancer with a hepatic metastasis, one patient had a hepatic angioma, one patient had an extraadrenal pheochromocytoma, one patient had an abscess in the iliopsoas muscle, 9 patients had myomas, two patients had ovarian simple cysts, two endometrial cysts, three dermoid cysts, one patient had sacrococcygeal teratoma, one patient had a cystadenofibroma (partial borderline tumor), one patient had an androgenic ovarian tumor and two patients had hyperreactio luteinalis. One patient was diagnosed with transient osteoporosis of the hip and one with a stress fracture of the sacral bone.

CONCLUSIONS

Magnetic resonance imaging is the best imaging modality for pregnant women. Although ultrasonography is the method of choice, doubtful cases as well as structures that cannot be examined with ultrasonography can be non-invasively evaluated with MRI.

Confirmation of posterior uterine rupture in the second trimester by magnetic resonance imaging

Intrapartum uterine rupture is a life-threating and rare complication of pregnancy which seldom occurs in the second trimester. Typically, the diagnosis is made using ultrasound; however, magnetic resonance imaging can provide certain advantages in the emergent setting. We present a unique case of a posterior uterine rupture confirmed by magnetic resonance imaging involving the unscarred posterior uterine wall in a 20-year-old gravid female with two previous cesarean-sections.

A Case of Intestinal Obstruction in Pregnancy Diagnosed by MRI and Treated by Intravenous Hyperalimentation

Intestinal obstruction in pregnancy is rare and is mainly caused by prior pelvic surgery. We herein report a case of intestinal obstruction in a pregnant female with a history of laparoscopic myomectomy, who presented with hypogastric pain, abdominal distension, and vomiting at 26 weeks of gestation. A simple intestinal obstruction was diagnosed by MRI. Conservative treatments, including intravenous hyperalimentation and the placement of an ileus tube, were provided and her abdominal symptoms improved for 14 days. After restarting oral intake, she had no abdominal symptoms. She gave birth to a 2,146 g female infant by caesarean section at 37 weeks and 1 day of gestation. Although an area of cicatrization, which was thought to have been the starting point of the occlusion that caused the intestinal obstruction, was found, the excision of the small intestine was not necessary. Her postoperative course was uneventful. Intestinal obstruction requires a prompt diagnosis and aggressive intervention may be necessary to minimize the morbidity and mortality associated with this rare complication of pregnancy. MRI can be safely used during pregnancy to diagnose intestinal obstruction and intravenous hyperalimentation may improve the maternal and fetal prognoses.

Committee Opinion No. 656: Guidelines for Diagnostic Imaging During Pregnancy and Lactation

Imaging studies are important adjuncts in the diagnostic evaluation of acute and chronic conditions. However, confusion about the safety of these modalities for pregnant and lactating women and their infants often results in unnecessary avoidance of useful diagnostic tests or the unnecessary interruption of breastfeeding. Ultrasonography and magnetic resonance imaging are not associated with risk and are the imaging techniques of choice for the pregnant patient, but they should be used prudently and only when use is expected to answer a relevant clinical question or otherwise provide medical benefit to the patient. With few exceptions, radiation exposure through radiography, computed tomography scan, or nuclear medicine imaging techniques is at a dose much lower than the exposure associated with fetal harm. If these techniques are necessary in addition to ultrasonography or magnetic resonance imaging or are more readily available for the diagnosis in question, they should not be withheld from a pregnant patient. Breastfeeding should not be interrupted after gadolinium administration.

The postpartum ultrasound scan

Ultrasound assessment of the postpartum uterus has a significant role to play in the evaluation of a large proportion of symptomatic puerperal women. Often the imaging modality of choice for excluding retained placental tissue, correct application of postpartum ultrasound could enable more accurate identification of women requiring surgical intervention, with consequent reduction in patient morbidity and clinical workload. This article aims to review the current understanding and application of ultrasound in the puerperium and evaluate the current evidence investigating the physiological and pathological findings of the postpartum uterus and its contents.

Magnetic resonance imaging - A troubleshooter in obstetric emergencies: A pictorial review

The application of magnetic resonance imaging (MRI) in pregnancy faced initial skepticism of physicians because of fetal safety concerns. The perceived fetal risk has been found to be unwarranted and of late, the modality has attained acceptability. Its role in diagnosing fetal anomalies is well recognized and following its safety certification in pregnancy, it is finding increasing utilization during pregnancy and puerperium. However, the use of MRI in maternal emergency obstetric conditions is relatively limited as it is still evolving. In early gestation, ectopic implantation is one of the major life-threatening conditions that are frequently encountered. Although ultrasound (USG) is the accepted mainstay modality, the diagnostic predicament persists in many cases. MRI has a role where USG is indeterminate, particularly in the extratubal ectopic pregnancy. Later in gestation, MRI can be a useful adjunct in placental disorders like previa, abruption, and adhesion. It is a good problem-solving tool in adnexal masses such as ovarian torsion and degenerated fibroid, which have a higher incidence during pregnancy. Catastrophic conditions like uterine rupture can also be preoperatively and timely diagnosed. MRI has a definite role to play in postpartum and post-abortion life-threatening conditions, e.g., retained products of conception, and gestational trophoblastic disease, especially when USG is inconclusive or inadequate.

Magnetic Resonance Imaging of Abdominal and Pelvic Pain in the Pregnant Patient

The utility of MR imaging in evaluating abdominal and pelvic pain in the pregnant patient is discussed. Details regarding the indications, technical aspects, and imaging findings of various common abdominal and pelvic abnormalities in pregnancy are reviewed.