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1.
Radiol Clin North Am ; 58(2): 381-399, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32044013

RESUMO

Placenta is a vital organ that connects the maternal and fetal circulations, allowing exchange of nutrients and gases between the two. In addition to the fetus, placenta is a key component to evaluate during any imaging performed during pregnancy. The most common disease processes involving the placenta include placenta accreta spectrum disorders and placental masses. Several systemic processes such as infection and fetal hydrops can too affect the placenta; however, their imaging features are nonspecific such as placental thickening, heterogeneity, and calcifications. Ultrasound is the first line of imaging during pregnancy, and MR imaging is reserved for problem solving, when there is need for higher anatomic resolution.


Assuntos
Descolamento Prematuro da Placenta/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Placenta Acreta/diagnóstico por imagem , Placenta Prévia/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Feminino , Humanos , Placenta/diagnóstico por imagem , Gravidez
2.
J Matern Fetal Neonatal Med ; 33(1): 162-166, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29888988

RESUMO

Objective: We aimed to review a single-center experience in follow-up and management of fetuses with umbilical vein varix (UVV) and to assess the effect of UVV on fetal Doppler parameters.Methods: We reviewed retrospectively maternal antenatal records, delivery records, and newborn records to identify cases of UVV. Further, we retrospectively compared 25 fetuses with isolated UVV and available cerebroplacental ratio (CPR) analysis with 75 matched controls.Results: We identified 67 cases of UVV. The median gestational age (GA) at diagnosis was 34 weeks (range: 26-41 weeks). The average diameter of UVV at diagnosis was 10.1 mm (range: 9-14 mm). The median GA at delivery was 36 + 6 (range: 33-41 weeks), with an average birth weight of 2918 g (range: 1278-4140 g). There was a single case of intrauterine death at 35 weeks. CPR was 2.13 ± 0.62 in isolated UVV group compared with 1.84 ± 0.61 in the control group (p < .05). Other Doppler parameters did not differ between fetuses with UVV compared with controls.Conclusions: CPR was significantly increased in the UVV group compared with control fetuses. This finding suggests that UVV is not associated with chronic fetal oxygen deprivation; it, therefore, may contribute to our understanding of the pathophysiology explaining abnormal pregnancy outcome in cases with UVV.


Assuntos
Cefalometria , Retardo do Crescimento Fetal/etiologia , Placenta/diagnóstico por imagem , Artérias Umbilicais/irrigação sanguínea , Varizes/diagnóstico , Adulto , Estudos de Casos e Controles , Feminino , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/epidemiologia , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiologia , Placenta/anatomia & histologia , Placenta/irrigação sanguínea , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Fluxo Pulsátil , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/patologia , Veias Umbilicais/irrigação sanguínea , Veias Umbilicais/diagnóstico por imagem , Veias Umbilicais/patologia , Varizes/complicações , Varizes/epidemiologia
3.
Top Magn Reson Imaging ; 28(5): 285-297, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31592995

RESUMO

The Human Placenta Project has focused attention on the need for noninvasive magnetic resonance imaging (MRI)-based techniques to diagnose and monitor placental function throughout pregnancy. The hope is that the management of placenta-related pathologies would be improved if physicians had more direct, real-time measures of placental health to guide clinical decision making. As oxygen alters signal intensity on MRI and oxygen transport is a key function of the placenta, many of the MRI methods under development are focused on quantifying oxygen transport or oxygen content of the placenta. For example, measurements from blood oxygen level-dependent imaging of the placenta during maternal hyperoxia correspond to outcomes in twin pregnancies, suggesting that some aspects of placental oxygen transport can be monitored by MRI. Additional methods are being developed to accurately quantify baseline placental oxygenation by MRI relaxometry. However, direct validation of placental MRI methods is challenging and therefore animal studies and ex vivo studies of human placentas are needed. Here we provide an overview of the current state of the art of oxygen transport and quantification with MRI. We suggest that as these techniques are being developed, increased focus be placed on ensuring they are robust and reliable across individuals and standardized to enable predictive diagnostic models to be generated from the data. The field is still several years away from establishing the clinical benefit of monitoring placental function in real time with MRI, but the promise of individual personalized diagnosis and monitoring of placental disease in real time continues to motivate this effort.


Assuntos
Hiperóxia/diagnóstico por imagem , Hiperóxia/patologia , Imagem por Ressonância Magnética/métodos , Oxigênio/sangue , Placenta/diagnóstico por imagem , Placenta/patologia , Animais , Feminino , Humanos , Gravidez
4.
BMC Pregnancy Childbirth ; 19(1): 336, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521118

RESUMO

BACKGROUND: Affecting approximately 10% of pregnancies, fetal growth restriction (FGR), is the most important cause of perinatal mortality and morbidity. Impaired placental function and consequent mal-perfusion of the placenta is the leading cause of FGR. Although, screening for placental insufficiency based on uterine artery Doppler measurement is well established, there is no treatment option for pregnancies threatened by FGR. The organic nitrate pentaerithrityl tetranitrate (PETN) is widely used for the treatment of cardiovascular disease and has been shown to have protective effects on human endothelial cells. In a randomized placebo controlled pilot-study our group could demonstrate a risk reduction of 39% for the development of FGR, and FGR or death, by administering PETN to patients with impaired uterine artery Doppler at mid gestation. To confirm these results a prospective randomized placebo controlled double-blinded multicentre trial was now initiated. METHOD: The trial has been initiated in 14 centres in Germany. Inclusion criteria are abnormal uterine artery Doppler, defined by mean PI > 1.6, at 190 to 226 weeks of gestation in singleton pregnancies. Included patients will be monitored in 4-week intervals. Primary outcome measures are development of FGR (birth weight < 10th percentile), severe FGR (birth weight < 3rd centile) and perinatal death. Placental abruption, birth weight below the 3rd, 5th and 10th centile, development of FGR requiring delivery before 34 weeks` gestation, neonatal intensive care unit admission, and spontaneous preterm delivery < 34 weeks` and 37 weeks` gestation will be assessed as secondary endpoints. Patient enrolment was started in August 2017. Results are expected in 2020. DISCUSSION: During the past decade therapeutic agents with possible perfusion optimizing potential have been evaluated in clinical trials to treat FGR. Meta-analysis and sub-analysis of trials targeting preeclampsia revealed ASS to have a potential in reducing FGR. Phosphodiesterase-type-5 inhibitors have recently been tested in a worldwide RCT for therapy of established FGR, failing to show an effect on neonatal outcome. The ongoing multicenter trial will, by confirming our previous results, finally provide a therapeutic option in cases at risk for FGR. TRIAL REGISTRATION: DRKS00011374 registered at September 29th, 2017 and NCT03669185 , registered September 13th, 2018.


Assuntos
Retardo do Crescimento Fetal , Tetranitrato de Pentaeritritol , Placenta , Ultrassonografia Pré-Natal/métodos , Artéria Uterina/diagnóstico por imagem , Adulto , Feminino , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/tratamento farmacológico , Retardo do Crescimento Fetal/etiologia , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Tetranitrato de Pentaeritritol/administração & dosagem , Tetranitrato de Pentaeritritol/efeitos adversos , Imagem de Perfusão/métodos , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Insuficiência Placentária/diagnóstico , Insuficiência Placentária/tratamento farmacológico , Insuficiência Placentária/etiologia , Gravidez , Resultado da Gravidez , Ultrassonografia Doppler/métodos , Vasodilatadores/administração & dosagem , Vasodilatadores/efeitos adversos
5.
J Med Ultrason (2001) ; 46(4): 481-487, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31392444

RESUMO

PURPOSE: To evaluate a system for assessing the risk of pernicious placenta previa (PPP) with placenta accreta spectrum (PAS) disorders and poor pregnancy outcomes. METHODS: This prospective study focused on PPP women at ≥ 28 weeks' pregnancy. Transabdominal or transvaginal ultrasonography was used to assess PAS and poor pregnancy outcomes with a system involving uteroplacental demarcation, number and size of lacunae, bladder line, and placental basal and lacunae flow. Every item was assigned 0-2 points, and the sum yielded the final score. Diagnosis of PAS was based on surgery or pathology. One or more of postpartum hemorrhage (PPH) ≥ 1000 ml, hysterectomy, and organ invasion were regarded as a poor pregnancy outcome. Receiver operating characteristic (ROC) curves were generated. RESULTS: Fifty-one PPP women were included, with 70.6% having PAS and 75.0% of PAS women having a poor pregnancy outcome. The incidence of PAS diagnosis was 36.4% for those with a score < 5 points, with 0% having a poor outcome; 76.5% for those with a score ≥ 5 to < 8 points, with 61.5% having a poor outcome; and 100% for those with a score ≥ 8 points, with 100% having a poor pregnancy outcome. CONCLUSION: The system for predicting PPP with PAS and poor pregnancy outcomes was of high accuracy.


Assuntos
Placenta Acreta/diagnóstico por imagem , Placenta Acreta/epidemiologia , Placenta Prévia/diagnóstico por imagem , Placenta Prévia/epidemiologia , Resultado da Gravidez/epidemiologia , Ultrassonografia Pré-Natal/métodos , Adulto , Comorbidade , Feminino , Humanos , Placenta/diagnóstico por imagem , Gravidez , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes
6.
Eur Radiol ; 29(11): 6149-6151, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31392479

RESUMO

This editorial comment refers to the article "Identification of suspicious invasive placentation based on clinical MRI data using textural features and automated machine learning" by Sun et al. in European Radiology. KEY POINTS: • Understanding how the placenta works is one of the major challenges facing radiologists. • New perspectives are opening up for MRI studies of the placenta. • The authors propose a new approach to placental MRI based on texture analysis and machine learning.


Assuntos
Aprendizado de Máquina , Imagem por Ressonância Magnética/métodos , Placenta/diagnóstico por imagem , Radiologistas , Feminino , Humanos , Gravidez
7.
Comput Methods Programs Biomed ; 179: 104984, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31443859

RESUMO

BACKGROUND AND OBJECTIVE: Optimal development of placental vasculature is critical for fetal growth and health outcomes. Many studies characterizing the vascular structure of the fetal side of the placenta have utilized a range of two-dimensional and three-dimensional (3D) imaging techniques including X-ray micro-computed tomography (micro-CT) following perfusion of the vasculature with a radio-opaque compound. The CT approach has been used to study feto-placental vasculature in rodents and humans. Its inherent advantage is that it reveals the 3D structure in high resolution without destroying the sample. This permits both multiple scanning of the sample and follow-up histological investigations in the same sample. Nevertheless, the applicability of the approach is hampered both by the challenging segmentation of the vasculature and a lack of straightforward methodology to quantitate the feto-placental vascular network. This paper addresses these challenges. METHODS: An end-to-end methodology is presented for automatically segmenting the vasculature; obtaining a Strahler-ordered rooted-tree representation and extracting quantitative features from its nodes, segments and branches (including volume, length, tortuosity and branching angles). The methodology is demonstrated for rat and mouse placentas at the end of gestation (day 22 and day 18, respectively), perfused with Microfil® and imaged using two different micro-CT scanners. RESULTS: The 3D visualizations of the resulting vascular trees clearly demonstrate differences between the branching complexity, tree span and tree depth of the mouse and rat placentas. The quantitative characterizations of these trees include not only the fundamental features that have been utilized in other studies of feto-placental vasculature but also several additional features. Boxplots of several of these-tortuosity, number of side branches, number of offspring per branch and branch volume-computed at each Strahler order are presented and interpreted. Differences and similarities between the mouse and rat casts are readily detected. CONCLUSION: The proposed end-to-end methodology, and the implementation presented using a combination of Amira and Matlab, offers researchers in the field of placental vasculature characterization a straightforward and objective approach for quantifying micro-CT vascular datasets.


Assuntos
Feto/irrigação sanguínea , Placenta/irrigação sanguínea , Circulação Placentária/fisiologia , Algoritmos , Animais , Feminino , Desenvolvimento Fetal , Feto/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Camundongos , Modelos Cardiovasculares , Placenta/diagnóstico por imagem , Placentação , Gravidez , Interpretação de Imagem Radiográfica Assistida por Computador/estatística & dados numéricos , Ratos , Microtomografia por Raio-X/estatística & dados numéricos
8.
Comput Methods Programs Biomed ; 179: 104993, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31443866

RESUMO

Twin-to-twin transfusion syndrome (TTTS) is a serious condition that may occur in pregnancies when two or more fetuses share the same placenta. It is characterized by abnormal vascular connections in the placenta that cause blood to flow unevenly between the babies. If left untreated, perinatal mortality occurs in 90% of cases, whilst neurological injuries are still present in TTTS survivors. Minimally invasive fetoscopic laser surgery is the standard and optimal treatment for this condition, but is technically challenging and can lead to complications. Acquiring and maintaining the required surgical skills need consistent practice, and a steep learning curve. An accurate preoperative planning is thus vital for complex TTTS cases. To this end, we propose the first TTTS fetal surgery planning and simulation platform. The soft tissue of the mother, the uterus, the umbilical cords, the placenta and its vascular tree are segmented and registered automatically from magnetic resonance imaging and 3D ultrasound using computer vision and deep learning techniques. The proposed state-of-the-art technology is integrated into a flexible C++ and MITK-based application to provide a full exploration of the intrauterine environment by simulating the fetoscope camera as well as the laser ablation, determining the correct entry point, training doctors' movements and trajectory ahead of operation, which allows improving upon current practice. A comprehensive usability study is reported. Experienced surgeons rated highly our TTTS planner and simulator, thus being a potential tool to be implemented in real and complex TTTS surgeries.


Assuntos
Transfusão Feto-Fetal/cirurgia , Fetoscopia/métodos , Modelos Anatômicos , Algoritmos , Gráficos por Computador , Simulação por Computador , Feminino , Transfusão Feto-Fetal/diagnóstico por imagem , Fetoscopia/estatística & dados numéricos , Humanos , Imageamento Tridimensional , Recém-Nascido , Terapia a Laser/métodos , Terapia a Laser/estatística & dados numéricos , Imagem por Ressonância Magnética/estatística & dados numéricos , Modelagem Computacional Específica para o Paciente/estatística & dados numéricos , Placenta/diagnóstico por imagem , Gravidez , Interface Usuário-Computador , Útero/diagnóstico por imagem
9.
EMBO J ; 38(18): e100849, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31424120

RESUMO

The placenta is an autonomous organ that maintains fetal growth and development. Its multinucleated syncytiotrophoblast layer, providing fetal nourishment during gestation, exhibits characteristics of cellular senescence. We show that in human placentas from pregnancies with intrauterine growth restriction, these characteristics are decreased. To elucidate the functions of pathways regulating senescence in syncytiotrophoblast, we used dynamic contrast-enhanced MRI in mice with attenuated senescence programs. This approach revealed an altered dynamics in placentas of p53-/- , Cdkn2a-/- , and Cdkn2a-/- ;p53-/- mice, accompanied by histopathological changes in placental labyrinths. Human primary syncytiotrophoblast upregulated senescence markers and molecular pathways associated with cell-cycle inhibition and senescence-associated secretory phenotype. The pathways and components of the secretory phenotype were compromised in mouse placentas with attenuated senescence and in human placentas from pregnancies with intrauterine growth restriction. We propose that molecular mediators of senescence regulate placental structure and function, through both cell-autonomous and non-autonomous mechanisms.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Retardo do Crescimento Fetal/genética , Redes Reguladoras de Genes , Placenta/diagnóstico por imagem , Proteína Supressora de Tumor p53/genética , Animais , Senescência Celular , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Humanos , Imagem por Ressonância Magnética , Camundongos , Fenótipo , Placenta/metabolismo , Gravidez , Transdução de Sinais , Trofoblastos/metabolismo
10.
Eur J Obstet Gynecol Reprod Biol ; 240: 197-204, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31323500

RESUMO

Low-positioned placentas which are located in the lower uterine segment (LUS), either a low-lying placenta or a placenta previa, are associated with increased obstetric risks. However, most second trimester low-positioned placentas resolve during pregnancy and have a higher position in the third trimester, without posing any risks. We performed a systematic review and meta-analysis to evaluate the proportion of second trimester low-positioned placentas that have a position towards the fundus in the third trimester. Our aim was to find a cut-off value that included all women in whom the placenta will remain low in the third trimester, thus who are at increased risk of obstetric complications. Subsequently, we assessed whether an anterior or posterior placental location influenced this proportion. We searched MEDLINE and EMBASE and clinicaltrials.gov up to April 2019 for studies on the sonographic follow-up of second trimester low-positioned placentas, with a distance between the placenta and the internal os of the cervix of 20 mm or less at a gestational age of above 15 week and a follow up after 28 weeks. Studies were scored on methodological quality using the Newcastle-Ottowa Scale (NOS). A meta-analysis was conducted to summarize the proportion of second trimester low-positioned placentas with a position towards the fundus in the third trimester. We calculated the proportion at different cut-off values of the distance from the placental edge to the internal os of the cervix (0 mm, 10 mm and 20 mm). Also, anteriorly and posteriorly located placentas and women with and without a prior cesarean delivery were compared. We included 11 eligible studies which reported on 3586 women with a low-positioned placenta in the second trimester. Proportions of placentas with a position towards the fundus in the third trimester ranged between 0.63 and 1.0. Pooled proportions were 0.90 (95% CI 0.87-0.93) for IOD <10 mm and 0.80 (95% CI 0.74-0.85) for IOD < 0 mm. Due to heterogeneity between studies, the subgroup of <20 mm could not be pooled. Overall, anteriorly located placentas more often had a position towards the fundus in the third trimester, but studies did report conflicting results. Prior cesarean section had no influence except for an IOD of <0 mm, in which women without a prior cesarean delivery more often had a placenta towards the fundus. The majority of second trimester low-positioned placentas will be located towards the fundus at the time of follow-up. However, we could not determine a cut-off value for anterior and posterior placentas that included all women at high risk. The cut-off value, placental side and prior cesarean section should be assessed in a large prospective observational study.


Assuntos
Placenta Prévia/diagnóstico por imagem , Placenta/diagnóstico por imagem , Segundo Trimestre da Gravidez , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Resultado da Gravidez
11.
Taiwan J Obstet Gynecol ; 58(4): 454-459, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307732

RESUMO

The abnormal development of placental vascularization leads to placental insufficiency, which further reduces the nutrient and trace exchange between maternal circulation and fetal circulation. These changes cause maternal and fetal complications. The objective of our systematic review was to explore the effects of maternal smoking on placental vascularization. The eligibility criteria were: articles with experimental, quasi-experimental or observational design, performed on human subjects, that study the association, correlation or causation between maternal smoking and changes in placental vascular network. A total of 33 full-text papers were assessed for eligibility, resulting in 12 original articles that were included in the systematic review. Doppler studies confirm reductions in blood flow velocity waveforms and increase in RI in the uterine, umbilical and fetal middle cerebral arteries. These findings are confirmed by morphometric measurements of fetal capillaries in villi that were shown to be smaller in smoke exposure groups.


Assuntos
Descolamento Prematuro da Placenta/etiologia , Exposição Materna/efeitos adversos , Insuficiência Placentária/diagnóstico por imagem , Resultado da Gravidez , Nascimento Prematuro/etiologia , Fumar/efeitos adversos , Descolamento Prematuro da Placenta/fisiopatologia , Adulto , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Insuficiência Placentária/fisiopatologia , Gravidez , Nascimento Prematuro/fisiopatologia , Medição de Risco , Ultrassonografia Pré-Natal/métodos
12.
Theriogenology ; 138: 16-23, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31280181

RESUMO

The main purpose of examining multiparous species with real-time ultrasonography is to determine the gestational age and make various fetal measurements for early diagnosis of growth anomalies and sibling mismatches. This study investigated changes in fetometric measurements, obstetric Doppler indices and placental image analysis results based on gestational age and fetal location in fetuses located cranially and caudally between 16 and 24 days gestation in 22 healthy pregnant New Zealand rabbits. The first study group consisted of fetuses positioned at the cranial end (n = 22) while the second group consisted of fetuses positioned at the caudal end (n = 22) in each pregnancy. Fetal biparietal head diameter (BPD) and trunk diameter (TD) were measured, and mean grayness values (MGV) were determined from placental image analysis of each fetus. Using Doppler USG, the pulsatile (PI) and resistance (RI) indices of the uterine artery (UtA) and umbilical artery (UmA) were recorded. By the end of the study, BPD and TD values for cranial and caudal fetuses had significantly increased with gestational age (P < 0.001). The MGV values of caudal fetuses were significantly higher (except for the 16th day) (P < 0.05). The UtA PI value of the caudal fetuses was significantly higher (except for the 18th day) (P < 0.01). The UtA RI values of caudal fetuses were significantly higher than cranial ones on the 16 and 24th days (P < 0.05). The PI of the UmA increased until the 20th day before decreasing significantly in both study groups (P < 0.001). The UmA RI value decreased according to the gestational age in both groups (P < 0.001). It was significantly higher in the caudal fetuses on the 20th day (P < 0.05). The somatic rate of all fetuses peaked at the end of the second trimester, although caudal fetuses had higher fetometric values, and this location difference also affected placental echotexture. In both vessels of caudal fetuses, pulsatility and resistance values were higher. The 20th day of pregnancy was a threshold for the Doppler exam results. In conclusion, growth and metabolic status of fetuses located in different uterine locations in healthy pregnant New Zealand rabbits vary. Based on the these growth curves and hemodynamic data, more comprehensive studies of intrauterine life may be possible.


Assuntos
Feto/diagnóstico por imagem , Placenta/diagnóstico por imagem , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem , Útero/diagnóstico por imagem , Animais , Velocidade do Fluxo Sanguíneo , Feminino , Feto/irrigação sanguínea , Idade Gestacional , Hemodinâmica , Tamanho da Ninhada de Vivíparos , Placenta/irrigação sanguínea , Circulação Placentária/fisiologia , Gravidez , Fluxo Pulsátil , Coelhos , Ultrassonografia Doppler , Ultrassonografia Pré-Natal/métodos , Ultrassonografia Pré-Natal/veterinária , Artérias Umbilicais/fisiologia , Artéria Uterina/fisiologia , Útero/irrigação sanguínea
13.
Medicine (Baltimore) ; 98(26): e16166, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31261546

RESUMO

RATIONALE: The placenta membranacea (PM) is a rare type of placental abnormality, which is associated with placenta previa, antepartum hemorrhage (APH), postpartum hemorrhage (PPH), chorioamnionitis, fetal growth restriction (FGR), preterm birth even stillbirth. The purpose of this case report is to summarize the characteristics and analyze the relevant factors of PM. PATIENTS CONCERNS: Repetitive B-ultrasound of the first patient demonstrated a thin placenta covering the most part of uterine wall, which completely covers the internal cervical ostium for 22 weeks. B-ultrasound of the second patient showed placenta partially covering the internal cervical ostium and fetus small for gestation age for 23 days. The third patient complained of abdominal pain and vaginal discharge for 1 day. DIAGNOSES: Diagnosis of PM is based on Doppler ultrasound apparatus, and confirmed by pathology. INTERVENTIONS AND OUTCOMES: In the first patient, elective cesarean section was performed. The second patient required termination of pregnancy due to poor postnatal outcome. The third patient underwent intrauterine fetal death. Of these 3 cases, one delivered a term fetus by cesarean section complicated with placenta previa and placenta accreta, one terminated the pregnancy because of serious fetal growth retardation, and the other underwent intrauterine fetal death. LESSONS: High-resolution color Doppler ultrasound apparatus can improve the diagnostic accuracy, and close antenatal surveillance followed by proper arrangement of delivery may improve neonatal outcomes.


Assuntos
Placenta/anormalidades , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Placenta/diagnóstico por imagem , Placenta/patologia , Gravidez , Resultado da Gravidez , Ultrassonografia Doppler em Cores , Ultrassonografia Pré-Natal , Adulto Jovem
14.
Vet J ; 249: 80-81, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31239170

RESUMO

Combined thickness of the uterus and placenta (CTUP) has been used for many years to assess fetal well-being and placental health in the mare and most recently the combined thickness of the uterus and interplacentome region (CTUIR) in water buffalo. The aim of this study was to develop normal reference ranges in regards to the CTUIR in 25 Holstein cows throughout pregnancy. The CTUIR was measured every 30 days from 60 days of gestation until 270 days of gestation. Measurements were obtained by transrectal ultrasonography with the position of the ultrasound probe being placed cranial and lateral to the cervix. CTUIR measurements increased every month beginning with an average of 4.6mm at 60 days and culminating with an average thickness of 11.7mm at 270 days of gestation. The greatest increases in CTUIR thickness occurred during the first and second trimesters.


Assuntos
Bovinos/anatomia & histologia , Placenta/anatomia & histologia , Prenhez/fisiologia , Ultrassonografia/veterinária , Útero/anatomia & histologia , Animais , Bovinos/fisiologia , Feminino , Placenta/diagnóstico por imagem , Gravidez , Valores de Referência , Útero/diagnóstico por imagem
15.
Obstet Gynecol Clin North Am ; 46(2): 367-378, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31056137

RESUMO

Diagnostic ultrasound is a powerful tool in obstetrics/gynecology. It has multiple applications, but for every use there are potential pitfalls that can have significant deleterious effects. Guidelines and certifications have been implemented to enhance the safety of this technique.


Assuntos
Ginecologia/métodos , Obstetrícia/métodos , Ultrassonografia Pré-Natal , Ultrassonografia , Colo do Útero/diagnóstico por imagem , Feminino , Desenvolvimento Fetal , Doenças Fetais/diagnóstico por imagem , Feto/anormalidades , Feto/diagnóstico por imagem , Idade Gestacional , Humanos , Erros Médicos , Placenta/diagnóstico por imagem , Gravidez , Complicações na Gravidez/diagnóstico por imagem , Gravidez Múltipla , Nascimento Prematuro/diagnóstico por imagem
16.
Cochrane Database Syst Rev ; 5: CD012245, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31087568

RESUMO

BACKGROUND: Stillbirth affects 2.6 million pregnancies worldwide each year. Whilst the majority of cases occur in low- and middle-income countries, stillbirth remains an important clinical issue for high-income countries (HICs) - with both the UK and the USA reporting rates above the mean for HICs. In HICs, the most frequently reported association with stillbirth is placental dysfunction. Placental dysfunction may be evident clinically as fetal growth restriction (FGR) and small-for-dates infants. It can be caused by placental abruption or hypertensive disorders of pregnancy and many other disorders and factorsPlacental abnormalities are noted in 11% to 65% of stillbirths. Identification of FGA is difficult in utero. Small-for-gestational age (SGA), as assessed after birth, is the most commonly used surrogate measure for this outcome. The degree of SGA is associated with the likelihood of FGR; 30% of infants with a birthweight < 10th centile are thought to be FGR, while 70% of infants with a birthweight < 3rd centile are thought to be FGR. Critically, SGA is the most significant antenatal risk factor for a stillborn infant. Correct identification of SGA infants is associated with a reduction in the perinatal mortality rate. However, currently used tests, such as measurement of symphysis-fundal height, have a low reported sensitivity and specificity for the identification of SGA infants. OBJECTIVES: The primary objective was to assess and compare the diagnostic accuracy of ultrasound assessment of fetal growth by estimated fetal weight (EFW) and placental biomarkers alone and in any combination used after 24 weeks of pregnancy in the identification of placental dysfunction as evidenced by either stillbirth, or birth of a SGA infant. Secondary objectives were to investigate the effect of clinical and methodological factors on test performance. SEARCH METHODS: We developed full search strategies with no language or date restrictions. The following sources were searched: MEDLINE, MEDLINE In Process and Embase via Ovid, Cochrane (Wiley) CENTRAL, Science Citation Index (Web of Science), CINAHL (EBSCO) with search strategies adapted for each database as required; ISRCTN Registry, UK Clinical Trials Gateway, WHO International Clinical Trials Portal and ClinicalTrials.gov for ongoing studies; specialist abstract and conference proceeding resources (British Library's ZETOC and Web of Science Conference Proceedings Citation Index). Search last conducted in Ocober 2016. SELECTION CRITERIA: We included studies of pregnant women of any age with a gestation of at least 24 weeks if relevant outcomes of pregnancy (live birth/stillbirth; SGA infant) were assessed. Studies were included irrespective of whether pregnant women were deemed to be low or high risk for complications or were of mixed populations (low and high risk). Pregnancies complicated by fetal abnormalities and multi-fetal pregnancies were excluded as they have a higher risk of stillbirth from non-placental causes. With regard to biochemical tests, we included assays performed using any technique and at any threshold used to determine test positivity. DATA COLLECTION AND ANALYSIS: We extracted the numbers of true positive, false positive, false negative, and true negative test results from each study. We assessed risk of bias and applicability using the QUADAS-2 tool. Meta-analyses were performed using the hierarchical summary ROC model to estimate and compare test accuracy. MAIN RESULTS: We included 91 studies that evaluated seven tests - blood tests for human placental lactogen (hPL), oestriol, placental growth factor (PlGF) and uric acid, ultrasound EFW and placental grading and urinary oestriol - in a total of 175,426 pregnant women, in which 15,471 pregnancies ended in the birth of a small baby and 740 pregnancies which ended in stillbirth. The quality of included studies was variable with most domains at low risk of bias although 59% of studies were deemed to be of unclear risk of bias for the reference standard domain. Fifty-three per cent of studies were of high concern for applicability due to inclusion of only high- or low-risk women.Using all available data for SGA (86 studies; 159,490 pregnancies involving 15,471 SGA infants), there was evidence of a difference in accuracy (P < 0.0001) between the seven tests for detecting pregnancies that are SGA at birth. Ultrasound EFW was the most accurate test for detecting SGA at birth with a diagnostic odds ratio (DOR) of 21.3 (95% CI 13.1 to 34.6); hPL was the most accurate biochemical test with a DOR of 4.78 (95% CI 3.21 to 7.13). In a hypothetical cohort of 1000 pregnant women, at the median specificity of 0.88 and median prevalence of 19%, EFW, hPL, oestriol, urinary oestriol, uric acid, PlGF and placental grading will miss 50 (95% CI 32 to 68), 116 (97 to 133), 124 (108 to 137), 127 (95 to 152), 139 (118 to 154), 144 (118 to 161), and 144 (122 to 161) SGA infants, respectively. For the detection of pregnancies ending in stillbirth (21 studies; 100,687 pregnancies involving 740 stillbirths), in an indirect comparison of the four biochemical tests, PlGF was the most accurate test with a DOR of 49.2 (95% CI 12.7 to 191). In a hypothetical cohort of 1000 pregnant women, at the median specificity of 0.78 and median prevalence of 1.7%, PlGF, hPL, urinary oestriol and uric acid will miss 2 (95% CI 0 to 4), 4 (2 to 8), 6 (6 to 7) and 8 (3 to 13) stillbirths, respectively. No studies assessed the accuracy of ultrasound EFW for detection of pregnancy ending in stillbirth. AUTHORS' CONCLUSIONS: Biochemical markers of placental dysfunction used alone have insufficient accuracy to identify pregnancies ending in SGA or stillbirth. Studies combining U and placental biomarkers are needed to determine whether this approach improves diagnostic accuracy over the use of ultrasound estimation of fetal size or biochemical markers of placental dysfunction used alone. Many of the studies included in this review were carried out between 1974 and 2016. Studies of placental substances were mostly carried out before 1991 and after 2013; earlier studies may not reflect developments in test technology.


Assuntos
Desenvolvimento Fetal/fisiologia , Recém-Nascido Pequeno para a Idade Gestacional , Placenta/diagnóstico por imagem , Resultado da Gravidez , Ultrassonografia Pré-Natal , Feminino , Retardo do Crescimento Fetal , Humanos , Recém-Nascido , Mortalidade Perinatal , Gravidez , Natimorto
17.
Diagn Interv Radiol ; 25(4): 280-284, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31120426

RESUMO

PURPOSE: We aimed to compare the placental diffusion difference between intrauterine growth restriction (IUGR) patients with worsening Doppler ultrasonography (US) findings and control group with normal Doppler US findings by using diffusion-weighted imaging (DWI). METHODS: We performed a prospective study to compare the placental diffusion difference in 63 patients (gestational week, 28-34 weeks), including 50 IUGR patients (mean gestational week, 30 weeks 3 days ±16.2 days) with worsening Doppler US findings and 13 patients with normal Doppler US findings (mean gestational week, 29 weeks 4 days ±12.3 days) by using DWI (b value, 0-1000 s/mm2). We classified IUGR patients into three groups according to the reference values of the umbilical artery pulsatility index (PI) chart. Placenta apparent diffusion coefficient (ADC) calculations were performed by freehand drawn regions-of-interest (ROIs) (min, 8.04 cm2; max, 200 cm2). RESULTS: Placental ADC values in IUGR patients (mean, 1.624±0.181 ×10-³ mm²/s; range, 1.35-1.96 ×10-3 mm2/s) were significantly reduced compared with the control group (mean, 1.827±0.191 ×10-³ mm²/s; range, 1.35-2.84 ×10-3 mm2/s) (P = 0.001). For adjusted ROI area calculation, ADC values were significantly lower in groups 3, 2 and 1, respectively, compared with the control group (P < 0.05); and there was no significant difference between groups 1 and 2 (P > 0.05). Preeclampsia significantly reduced the placental diffusion compared with patients without preeclampsia (P = 0.003). Gestational aging did not significantly affect ADC values in control patients (r=0.08, P = 0.561). The sensitivity, specificity, negative and positive predictive values of ADC to detect IUGR were 72%, 84.6%, 44%, and 94.7% with a cutoff value of 1.727 ×10-3 mm2/s, respectively. CONCLUSION: The diagnostic estimation of placental ADC values to predict the severity of IUGR is comparable to that of umbilical artery PI. Considering that at the very early onset of IUGR, placental diffusion diminishes, ADC as a marker for IUGR in lieu of umbilical artery PI has the potential to determine the threshold for decreased placental diffusion. Therefore, DWI should be added to routine fetal MRI to show diffusion changes in placenta.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Retardo do Crescimento Fetal/diagnóstico por imagem , Placenta/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Feminino , Retardo do Crescimento Fetal/patologia , Feto/diagnóstico por imagem , Idade Gestacional , Humanos , Variações Dependentes do Observador , Pré-Eclâmpsia/fisiopatologia , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Fluxo Pulsátil/fisiologia , Radiologistas , Índice de Gravidade de Doença , Artérias Umbilicais/diagnóstico por imagem
18.
Clin Imaging ; 56: 135-139, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31030112

RESUMO

OBJECTIVE: Our primary aim was to investigate if women with placenta accreta can be differentiated with women without using IVIM quantitative assessment of the placental perfusion. A second aim was to investigate if IVIM parameters could be used to differentiate placenta accreta from increta. METHODS: The study population included 17 patients with placenta accreta, 29 patients with placenta increta and 16 patients without placenta accreta between 28 + 0 to 41 + 6 weeks. All women underwent a MRI examination including an IVIM sequence at 1.5 T. The perfusion fraction (f), pseudodiffusion coefficient (D*) and standard diffusion coefficient (D) were calculated. Results Women with placenta accreta and increta had a smaller placenta perfusion fraction (P < 0.05) than patients without placenta accreta, placental perfusion fraction didn't differ between placenta accreta and increta (p > 0.05). Differences of D and D* in three groups showed no statistical significance (p > 0.05). CONCLUSION: Placenta accreta and increta differ in placental perfusion fraction from women without the disease. The perfusion fraction can be used as a feasible index to evaluate placenta perfusion.


Assuntos
Imagem por Ressonância Magnética/métodos , Placenta Acreta/diagnóstico por imagem , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Adulto , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Adulto Jovem
19.
J Comput Assist Tomogr ; 43(3): 507-512, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30762655

RESUMO

PURPOSE: This study aimed to assess apparent diffusion coefficient (ADC) of the placenta and fetal organs in intrauterine growth restriction (IUGR). MATERIALS AND METHODS: A prospective study of 30 consecutive pregnant women (aged 21-38 years with mean age of 31.5 years and a mean gestational week of 35 ± 2.3) with IUGR and 15 age-matched pregnant women was conducted. All patients and controls underwent diffusion-weighted magnetic resonance imaging. The ADCs of the placenta and fetal brain, kidney, and lung were calculated and correlated with neonates needing intensive care unit (ICU) admission. RESULTS: There was a significant difference in ADC of the placenta and fetal brain, lung, and kidney (P = 0.001, 0.001, 0.04, and 0.04, respectively) between the patients and the controls. The cutoff ADCs of the placenta and fetal brain, lung, and kidney used to detect IUGR were 1.45, 1.15, 1.80, and 1.40 × 10 mm/s, respectively, with areas under the curve (AUCs) of 0.865, 0.858, 0.812, and 0.650, respectively, and accuracy values of 75%, 72.5%, 72.5%, and 70%, respectively. Combined ADC of the placenta and fetal organs used to detect IUGR revealed an AUC of 1.00 and an accuracy of 100%. There was a significant difference in ADC of the placenta and fetal brain, lung, and kidney between neonates needing admission and those not needing ICU admission (P = 0.001, 0.001, 0.002, and 0.002, respectively). The cutoff ADCs of the placenta and fetal brain, lung, and kidney used to define neonates needing ICU were 1.35, 1.25, 1.95, and 1.15 × 10 mm/s with AUCs of 0.955, 0.880, 0.884, and 0.793, respectively, and accuracy values of 86.7%, 46.7%, 76.7%, and 70%, respectively. Combined placental and fetal brain ADC used to define neonates needing ICU revealed an AUC of 0.968 and an accuracy of 93.3%. CONCLUSION: Combined ADC of the placenta and fetal organs can detect IUGR, and combined ADC of the placenta and fetal brain can define fetuses needing ICU.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Retardo do Crescimento Fetal/diagnóstico por imagem , Rim/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Placenta/diagnóstico por imagem , Encéfalo/embriologia , Feminino , Idade Gestacional , Humanos , Rim/embriologia , Pulmão/embriologia , Masculino , Idade Materna , Gravidez , Diagnóstico Pré-Natal , Estudos Prospectivos , Adulto Jovem
20.
BMJ Case Rep ; 12(1)2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30700468

RESUMO

A 27-year-old multigravida woman was noted on routine growth scan at 27 weeks gestation to have a central placental hypoechoic area measuring 6.7×6.0×4.4 cm. A subsequent magnetic resonance scan confirmed a solid mass in the placenta lying anteriorly; therefore, a preliminary diagnosis of giant placental chorioangioma was made. A repeat ultrasound scan at 30 weeks gestation indicated that the mass had increased, with the presence of polyhydramnios. The patient experienced reduced fetal movements at 31 weeks gestation. There was persistent fetal tachycardia at 33 weeks gestation, and consequently the neonate was delivered by emergency caesarean section. The placenta revealed a large chorioangioma. The neonate's birth weight was 2.85 kg and non-immune hydrops fetalis was diagnosed. The neonate improved significantly in the neonatal intensive care unit and is currently well with no medical problems.


Assuntos
Cesárea , Hemangioma/diagnóstico por imagem , Hidropisia Fetal/diagnóstico por imagem , Doenças Placentárias/diagnóstico por imagem , Poli-Hidrâmnios/diagnóstico por imagem , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Recém-Nascido , Imagem por Ressonância Magnética/métodos , Placenta/diagnóstico por imagem , Gravidez , Ultrassonografia Pré-Natal/métodos
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