Tools, Technologies and Frameworks for Digital Twins in the Oil and Gas Industry: An In-Depth Analysis.

The digital twin (DT), which involves creating a virtual replica of a physical asset or system, has emerged as a transformative set of tools across various industries. In the oil and gas (O&G) industry, the development of DTs represents a significant evolution in how companies manage complex operations, enhance safety, and optimize decision-making processes. Despite these significant advancements, the underlying tools, technologies, and frameworks for developing DTs in O&G applications remain non-standardized and unfamiliar to many O&G practitioners, highlighting the need for a systematic literature review (SLR) on the topic. Thus, this paper offers an SLR of the existing literature on DT development for O&G from 2018 onwards, utilizing Scopus and Web of Science Core Collection. We provide a comprehensive overview of this field, demonstrate how it is evolving, and highlight standard practices and research opportunities in the area. We perform broad classifications of the 98 studies, categorizing the DTs by their development methodologies, implementation objectives, data acquisition, asset digital development, data integration and preprocessing, data analysis and modeling, evaluation and validation, and deployment tools. We also include a bibliometric analysis of the selected papers, highlighting trends and key contributors. Given the increasing number of new DT developments in O&G and the many new technologies available, we hope to provide guidance on the topic and promote knowledge production and growth concerning the development of DTs for O&G.

El embarazo gemelar monocorial desde la perspectiva de la teoría de la complejidad / Monochorionic twin pregnancy from the perspective of the theory of complexity

En la práctica, es muy frecuente asociar las gestaciones gemelares monocoriales (MC) con embarazos complejos o complicados, utilizando ambos términos en forma intercambiable. Sin embargo, no lo son; el dinamismo es protagonista en los sistemas complejos, pero no en los complicados. Para entender a la embarazada con una gestación MC como un sistema complejo, primero se desarrollarán las características principales de los embarazos MC; su placenta es una de las principales responsables de los problemas. Luego se analizará el embarazo MC desde la complejidad, identificando las características del sistema y sus complicaciones como propiedades emergentes.

In practice, it is very common to associate monochorionic (MC) twin pregnancies with complex or complicated pregnancies, using both terms interchangeably. However, these are not synonyms; dynamism is the protagonist in complex systems, but not in complicated ones. In order to understand a MC pregnancy as a complex system, it is necessary to first look into its main characteristics. The placenta is one of the main sources of problems. Then, the MC pregnancy has to be analyzed from the perspective of complexity, identifying the system characteristics and its complications as emergent properties.

Genetics and sleep bruxism: a systematic review and meta-analysis of studies with twins.

OBJECTIVE: To systematically review the literature regarding the concordance of sleep bruxism (SB) between monozygotic (MZ) and dizygotic (DZ) twins. METHODS: The registration for this systematic review was accomplished in the International Prospective Register of Systematic Reviews (PROSPERO, No. CRD42021251751). As of July 2022, four databases were searched, including PubMed, Scopus, Embase, and Web of Science, as well as the grey literature in Google Scholar and OpenGrey. Observational studies evaluating SB in MZ and DZ twins of any age and sex were included. For the evaluation of the risk of bias, the Joanna Briggs checklist was utilized. The certainty of evidence was assessed via the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Pooled and subgroup meta-analyses were performed to estimate concordance of SB ​​between twins (p < 0.05). RESULTS: In total, 3,155 records were identified. In the qualitative analysis, eleven studies were included; of these, seven were included in the meta-analysis. The majority of the articles exhibited a low risk of bias (63.6%). Greater SB concordance was observed between MZ twins than between DZ twins in the analysis of general concordance (OR = 1.47; 95% CI = 1.07-2.02) and also positive concordance (OR = 1.53; 95% CI = 1.29-1.81). Within the subgroup analyses, the significance of the findings remained only for the reported/self-reported SB regarding general concordance (OR = 1.44; 95% CI = 1.07-1.95) and positive concordance (OR = 1.55; 95% CI = 1.28-1.88). Low certainty of the evidence was observed for the general concordance analysis, while moderate certainty was observed for the positive concordance. CONCLUSION: There was a higher concordance of SB in MZ twins compared to DZ twins, indicating a possible genetic influence on the condition's occurrence.

Prevention of preterm birth in twin-to-twin transfusion syndrome: a systematic review and network meta-analysis.

OBJECTIVES: We aimed to perform a systematic review and network meta-analysis to evaluate the preventive strategies for preterm birth in twin-to-twin transfusion syndrome. METHODS: PubMed, Embase and Cochrane Central were searched from inception to December 2023 with no filters. Additionally, the reference lists of the included studies were manually examined to identify any supplementary studies. We selected randomized controlled trials and cohorts comparing interventions to prevent preterm birth in twin pregnancies complicated by twin-to-twin transfusion syndrome. A random-effects frequentist network meta-analysis was performed using RStudio version 4.3.1. Randomized controlled trials and cohorts were assessed respectively using the Risk of Bias in Non-randomized Studies of interventions tool and Cochrane Collaboration's tool for assessing risk of bias in randomized trials. RESULTS: In this systematic review and meta-analysis, we included eight studies comprising a total of 719 patients. Compared with expectant management, cerclage stood out as the only intervention associated with an increase in the survival of at least one twin (risk ratio 1.12; 95 % confidence interval 1.01-1.23). Our subgroup analysis based on different thresholds for short cervix demonstrated a significant reduction in the risk of preterm birth before 32 weeks with ultrasound-indicated cerclage using a 15 mm criterion (risk ratio 0.65; 95 % confidence interval 0.47-0.92). CONCLUSIONS: Our study suggests the potential benefit of cerclage as a preventive strategy for preterm birth in pregnancies complicated by twin-to-twin transfusion syndrome. These findings highlight the necessity for further investigation to corroborate our results and address the optimal threshold for ultrasound-indicated cerclage.

Heterotopic twin pregnancy in unicornuate uterus and non-communicating rudimentary horn with survival of both fetuses: Magnetic resonance imaging and 3D reconstructions findings.

We reported a case of heterotopic twin pregnancy in a unicornuate uterus with a non-communicating rudimentary horn with survival of both fetuses. The diagnosis was made late at 28 weeks of gestation, with suspicion raised by ultrasound and confirmed by magnetic resonance imaging (MRI). During hospitalization, obstetric ultrasound with color Doppler was performed every 2 days to assess fetal well-being and myometrial thickness, which was determined by measurements of the uterine wall at the accessory horn. Elective cesarean section was performed at 33 + 5 weeks of gestation. Delivery started with the fetus in the rudimentary horn, with subsequent extraction of the fetus in the unicornate uterus. Three-dimensional virtual reconstruction allowed a spatial view of the both uterus and fetuses with better understanding of the obstetrical condition by the parents and interactive discussion by the multidisciplinary medical team.

Brazilian Twin Studies: A Scoping Review.

The current study was motivated by an interest in deepening understanding of Brazilian twin research, which is underrepresented internationally, in an effort to rectify this situation. Our aim was threefold: (1) to carry out a comprehensive investigation of Brazilian research on twins according to the area of knowledge; (2) to evaluate the representation of research in the field of psychology in comparison with other areas; (3) to evaluate characteristics of the research that may have contributed to its exclusion from the comprehensive meta-analysis of 50 years of twin research. A scoping review was performed according to PRISMA guidelines. Titles and abstracts were searched up to 2022 in six databases: CAPES, BDLTD, PePSIC, PubMed, Google Scholar, and SciELO, using selected keywords both in Portuguese and in English (e.g., 'twins' and 'Brazil'; 'twinning' and 'Brazil'; 'gemelaridade' [twinning], and 'gêmeos' [twins]). Three hundred and forty publications were included in the review. Approximately half (53.8‰) used the classic twin design to investigate the heritability of several traits, and the other half (46.2%) used other research designs. The scoping review showed that the number of publications doubled approximately every 10 years. Most publications were from the health area, with medicine accounting for approximately half of the studies, followed by psychology, odontology, and biology. We found that the interest in studying twins among Brazilian scientists is increasing over the years and there are reasons to be enthusiastic about the potential impact of this trend in the global scenario.

Monochorionic triplet pregnancy complicated by conjoined twins and early twin-twin transfusion syndrome.

BACKGROUND: The condition of monozygotic, monochorionic triplet fetuses with a pair of conjoined twins is extremely rare (close to one in a million births), presents challenges in its management, and with poor prognosis. CASE REPORT: We report a case of monochorionic diamniotic triplet pregnancy, ultrasound at 14 weeks shows a pair of conjoined thoracopagus fetuses, sharing heart, liver, and umbilical cord, in addition to omphalocele. The third fetus, without malformations, presents signs of early heart failure compatible with twin-to-twin transfusion syndrome. It was decided to carry out expectant management where at 18 weeks, intrauterine death of the three fetuses occurs. An abortion is performed by hysterotomy. CONCLUSIONS: The treatment in these cases is discussed, three management options have been proposed: expectant management, selective reduction of the conjoined fetuses, or termination of the pregnancy. A review of the literature found only 12 cases with this combination of pathologies, in which only 3 normal fetuses (25%) survived and none of the conjoined twins survived. To our knowledge, this case is the first of a monochorionic triplet pregnancy with conjoined fetuses complicated with early twin-to-twin transfusion.

Estereología en placentas procedentes de gestaciones gemelares / Stereology in placentas from twin pregnancies

Introducción: La disfunción placentaria origina complicaciones fetales; de manera más frecuente, la restricción del crecimiento intrauterino y la preclampsia. Objetivo: Identificar el patrón estereológico en placentas gemelares, y su relación con la corionicidad y el peso del recién nacido. Métodos: Se realizó un estudio descriptivo en una muestra de 16 gestantes gemelares, 25 placentas y 32 recién nacidos. Se estudiaron las variables peso del recién nacido, número de vellosidades, superficie vellositaria total, área vellositaria, área de nodos, densidad óptica de fibrina en la superficie vellositaria y densidad óptica de fibrina alrededor del vaso. Resultados: Existió relación directa entre el número de vellosidades y la superficie vellositaria total. En las placentas monocoriónicas hubo predominio de recién nacidos bajo peso. Se percibe una diferencia en los resultados de área, según el tipo placentario y la región topográfica. En las placentas monocoriales se observó mayor área, tanto de la vellosidad placentaria como en los nodos sincitiales, siendo el área de la vellosidad mayor en la periferia placentaria, y el área de nodos sincitiales en la región 4 cm del cordón umbilical. Conclusiones: La estereología microscópica a nivel pericordón, a 4 cm del cordón y en la periferia del disco placentario, arrojó diferencias significativas para el área de la vellosidad y la densidad óptica de fibrina en la superficie de la vellosidad. Los valores promedio para el área de nodos sincitiales y la densidad óptica de fibrina alrededor del vaso no mostraron diferencias estadísticamente significativas. Es la corionicidad un predictor del bajo peso al nacer(AU)

Introduction: Placental dysfunction causes fetal complications; more frequently, intrauterine growth restriction and preeclampsia. Objective: To identify the stereological pattern in twin placentas, and its relationship with chorionicity and weight of the newborn. Methods: A descriptive study was carried out in a sample of 16 women with twin pregnancy, 25 placentas and 32 newborns. The variables weight of the newborn, number of villi, total villous surface, villous area, node area, optical density of fibrin on the villous surface and optical density of fibrin around the vessel were studied. Results: There was a direct relationship between the number of villi and the total villous surface. In monochorionic placentas there was a predominance of low birth weight newborns. A difference is observed in the area results according to the placental type and the topographic region. In monochorionic placentas, a greater area was observed, both in the placental villus and in the syncytial nodes, with the villus area being greater in the placental periphery and the area of syncytial nodes in the region 4 cm from the umbilical cord. Conclusions: Microscopic stereology at the perichordal level, 4 cm from the cord and at the periphery of the placental disc showed significant differences for the villus area and fibrin optical density on the villus surface. The average values for the area of syncytial nodes and the optical density of fibrin around the vessel did not show statistically significant differences. Chorionicity is a predictor of low birth weight(AU)

Estimating the Genetic Contribution to Astigmatism and Myopia in the Mexican Population.

Astigmatism and myopia are two common ocular refractive errors that can impact daily life, including learning and productivity. Current knowledge suggests that the etiology of these conditions is the result of a complex interplay between genetic and environmental factors. Studies in populations of European ancestry have demonstrated a higher concordance of refractive errors in monozygotic (MZ) twins compared to dizygotic (DZ) twins. However, there is a lack of studies on genetically informative samples of multi-ethnic ancestry. This study aimed to estimate the genetic contribution to astigmatism and myopia in the Mexican population. A sample of 1399 families, including 243 twin pairs and 1156 single twins, completed a medical questionnaire about their own and their co-twin's diagnosis of astigmatism and myopia. Concordance rates for astigmatism and myopia were estimated, and heritability and genetic correlations were determined using a bivariate ACE Cholesky decomposition method, decomposed into A (additive genetic), C (shared environmental) and E (unique environmental) components. The results showed a higher concordance rate for astigmatism and myopia for MZ twins (.74 and .74, respectively) than for DZ twins (.50 and .55). The AE model, instead of the ACE model, best fitted the data. Based on this, heritability estimates were .81 for astigmatism and .81 for myopia, with a cross-trait genetic correlation of rA = .80, nonshared environmental correlation rE = .89, and a phenotypic correlation of rP = .80. These results are consistent with previous findings in other populations, providing evidence for a similar genetic architecture of these conditions in the multi-ethnic Mexican population.

Literature review of digital twin in healthcare.

This article aims to make a bibliometric literature review using systematic scientific mapping and content analysis of digital twins in healthcare to know the evolution, domain, keywords, content type, and kind and purpose of digital twin's implementation in healthcare, so a consolidation and future improvement of existing knowledge can be made and gaps for new studies can be identified. The increase in publications of digital twins in healthcare is quite recent and it is still concentrated in the domain of technology sources. The subject is majorly concentrated in patient's digital twin group and in precision medicine and aspects, issues and/or policies subgroups, although the publications keywords mirror it only at the group side. Digital twins in healthcare are probably stepping out of the infancy phase. On the other hand, digital twins in hospital group and the device and facilities management subgroups are more mature with all knowledge gathered from the manufacturing sector. There is an absence of some publication's types in general, device and care subgroup and no whole body or hospital digital twin was reported. Based on the presented arguments, guidelines for future research were presented: advance in the creation of general frameworks, in subgroups not as much explored, and in groups and subgroups already explored, but that need more advancement to achieve the main goals of a whole human or hospital digital twin with the main issues resolved.

Monochorionic twin pregnancy from the perspective of the theory of complexity. / El embarazo gemelar monocorial desde la perspectiva de la teoría de la complejidad.

In practice, it is very common to associate monochorionic (MC) twin pregnancies with complex or complicated pregnancies, using both terms interchangeably. However, these are not synonyms; dynamism is the protagonist in complex systems, but not in complicated ones. In order to understand a MC pregnancy as a complex system, it is necessary to first look into its main characteristics. The placenta is one of the main sources of problems. Then, the MC pregnancy has to be analyzed from the perspective of complexity, identifying the system characteristics and its complications as emergent properties.

En la práctica, es muy frecuente asociar las gestaciones gemelares monocoriales (MC) con embarazos complejos o complicados, utilizando ambos términos en forma intercambiable. Sin embargo, no lo son; el dinamismo es protagonista en los sistemas complejos, pero no en los complicados. Para entender a la embarazada con una gestación MC como un sistema complejo, primero se desarrollarán las características principales de los embarazos MC; su placenta es una de las principales responsables de los problemas. Luego se analizará el embarazo MC desde la complejidad, identificando las características del sistema y sus complicaciones como propiedades emergentes.

The Management of Acardiac Twinning: Twin Reverse Arterial Perfusion Sequence - An International Survey.

INTRODUCTION: The optimal approach and therapy method for the acardiac twin with a reverse arterial perfusion sequence has not yet been established. The aim of this study was to determine the clinical practice patterns among international fetal therapy units in their management of these cases. METHODS: A survey was sent to fetal centers across the world via email between December 2020 and December 2021. RESULTS: Responses were obtained from 77% contacted centers. The most frequent ultrasound variables used in the evaluation of twin reverse arterial perfusion sequence include echocardiographic assessment of the pump twin and umbilical artery Doppler waveforms in the acardiac and pump twins, in 90% and 80% of the centers, respectively. Most centers in Europe and Latin America propose an in utero intervention in all cases. Most centers in Europe and Latin America prefer interstitial laser ablation, whereas radiofrequency ablation (RFA) is preferred in North America. The earliest gestational age for an intervention is on mean 13 weeks in Europe, which is earlier than the other geographic areas (p = 0.001). CONCLUSIONS: Most centers agreed that antenatal evaluation should include echocardiography along with the UA Doppler waveform measurements, and the most frequently used interventions were interstitial laser ablation or RFA at a median between 14 and 26 weeks.

Characteristics of the oral glucose tolerance test in women with different pre-pregnancy body mass index and the effect of gestational diabetes mellitus on twin pregnancy outcomes.

OBJECTIVE: This study aimed to investigate the mid-pregnancy blood glucose levels of women with singleton or twin pregnancies. METHOD: The relationship between blood glucose levels and Gestational Diabetes Mellitus (GDM) was studied in women with different pre-pregnancy Body Mass Index (BMI), and the effect of GDM on twin pregnancy outcomes was analyzed. Women with twin (n = 1,985) and singleton (n = 1,985) pregnancies were categorized into underweight (BMI < 18.5 kg/m2, n = 597), normal weight (BMI: 18.5-23.9 kg/m2, n = 2,575), and overweight/obese (BMI ≥ 24 kg/m2, n = 798) groups. RESULTS: The incidence of GDM was 21.01% in women with twin pregnancies. Among the women with GDM in twin pregnancies, 38.37% had at least two abnormal blood glucose levels. The incidence of these parameters increased with preconception BMI, and the incidence of twin pregnancies was higher than that of singleton pregnancies (p < 0.001). In the normal weight and overweight/obese group, the oral glucose tolerance test glucose level and incidence of GDM were higher in women with twin than singleton pregnancies (p < 0.05). For twin pregnancies, the prevalence of selective fetal growth restriction was higher and anemia was lower in the GDM group than in the non-GDM group (all p < 0.05). CONCLUSION: Therefore, a greater emphasis should be placed on BMI before conception, and well-controlled GDM does not increase adverse pregnancy outcomes for twin pregnancies.

Ankyloglossia in Monochorionic Diamniotic and Dichorionic Diamniotic Twins: A Cross-Sectional Study.

Objective: To determine the prevalence of ankyloglossia in diamniotic monochorionic and diamniotic dichorionic twins, as well as to verify the relationship between gender and type of pregnancy. Study Design: A cross-sectional observational study, carried out with 52 pairs of dichorionic/diamniotic twins and 49 monochorionic/diamniotic pairs. The data collection was carried out through the analysis of medical records and the results of the Neonatal Screening of the Tongue Frenulum Assessment Protocol in Babies, and corresponded to the period of 2 years (2020-2022). Statistical analysis of data was performed, considering the significance value of 5%. The study was approved by the Human Research Ethics Committee of the institution. Results: The statistical analysis of multiple logistic regression between the two groups of twins (Mono/Di and Di/Di) according to the socioeconomic, demographic, and clinical-epidemiological profile was statistically significant for some variables. The prevalence of ankyloglossia, according to the type of twin pregnancy, showed a statistically significant difference. There was no statistical difference in relation to sex and ankyloglossia, or between couples diagnosed with ankyloglossia according to the type of pregnancy. Conclusion: Monochorionic/diamniotic twins had a higher prevalence of ankyloglossia, regardless of gender.

Management of Late Twin-to-Twin Transfusion Syndrome beyond 26 Weeks: Comparison between Fetoscopic Laser Therapy versus Traditional Management.

INTRODUCTION: A proportion of monochorionic diamniotic (MCDA) twin pregnancies complicated by twin-to-twin transfusion syndrome (TTTS) can present after 26 weeks of gestation. The aim of this study was to compare perinatal outcomes of late TTTS treated by fetoscopic laser coagulation versus traditional management with amniodrainage and/or emergency preterm cesarean delivery (CD). METHODS: Retrospective cohort from January 2012 to January 2023 of consecutive MCDA twin pregnancies complicated by TTTS after 26 weeks and evaluated in our referring centers. We analyzed perinatal outcomes of cases treated with fetoscopic laser surgery at our national referral fetal surgery center in Queretaro, Mexico, and compared them with those managed with traditional management (amniodrainage and/or emergency preterm CD). The primary outcome was survival at discharge and the secondary outcome was gestational age (GA) at birth. RESULTS: Among the study population, 46 TTTS cases were treated by fetoscopy at 27+6 (26+0-31+0) weeks+days and were compared with a group of 39 cases who underwent emergency preterm CD. In comparison to the group who underwent traditional management, the group treated by laser fetoscopy showed a significantly higher GA at birth (32+3 vs. 29+1 weeks+days, p < 0.001), lower frequency of preterm delivery below 37 weeks (91.3% vs. 100%, p = 0.06), 34 weeks (63.0% vs. 100%, p < 0.001), 32 weeks (50% vs. 74.4%, p = 0.02), or 30 weeks (28.3% vs. 53.8%, p = 0.01), and significantly higher perinatal survival (89.1% vs. 71.8%, p < 0.05 of at least one twin; and 65.2% vs. 38.5%, p = 0.01 of both twins, respectively). CONCLUSION: MCDA twins complicated with TTTS can be treated with fetoscopic laser surgery between 26 and 31 weeks of gestation, which is a feasible and safe option, and such cases are associated with a higher GA at birth and better perinatal survival than those managed with amniodrainage and/or emergency preterm CD.

Manejo del síndrome de transfusión feto fetal en pandemia COVID-19: reporte de caso

El síndrome de transfusión feto-fetal (STFF) es una complicación propia de los embarazos gemelares monocoriales, con mortalidad perinatal del 80 a 100%. Ocurre por un desequilibrio en el flujo sanguíneo placentario entre ambos gemelos. El diagnóstico se basa en la discordancia del líquido amniótico y luego se clasifica en estadios según los criterios de Quintero. El tratamiento principal es la fetoscopia y fotoablación con energía láser (FFL) de las anastomosis placentarias. Presentamos un caso de gestación gemelar monocorial biamniótica tratado con FFL en plena cuarentena e inmovilización de la pandemia COVID-19 en Perú, que incluyó diagnóstico oportuno y referencia rápida para recibir el tratamiento especializado.

The twin-to-twin transfusion syndrome (TTTS) is a potentially lethal complication that can occur in monochorionic twin pregnancies due to an imbalance in placental blood flow. Diagnosis is based on amniotic fluid discordance and classified using the Quintero staging system. The primary treatment is fetoscopic laser photocoagulation (FLP) of placental anastomoses. A successful case of FLP treatment in a monochorionic diamniotic twin pregnancy with TTTS during COVID-19 pandemic in Peru is presented.

Morfometría en placentas procedentes de embarazos gemelares / Morphometry in placentas from twin pregnancies

Introducción: La disfunción de la placenta puede originar complicaciones fetales, restricción del crecimiento intrauterino y complicaciones maternas, como la preeclampsia. Objetivo: Identificar el patrón morfométrico de las placentas gemelares y su relación con la corionicidad, el peso del recién nacido y las malformaciones plancentarias. Método: Se realizó un estudio descriptivo en una muestra de 16 gestantes con embarazo gemelar, 25 placentas y los 32 recién nacidos. Se estudiaron las variables malformaciones placentarias, tipo de placenta, presencia de calcificaciones, peso del recién nacido, peso de la placenta, volumen placentario, diámetro placentario y espesor placentario; se determinó la asociación del peso del recién nacido, con el tipo de placenta y la presencia de calcificaciones, las malformaciones placentarias, así como espesor, diámetro, volumen y peso, con el tipo de placenta. Resultados: Hubo mayor frecuencia de recién nacidos de placentas monocoriónicas (60 por ciento) sin que la asociación fuera estadísticamente significativa; las malformaciones placentarias se relacionaron de forma significativa con el tipo de placenta, así como el peso del recién nacido y la presencia de calcificaciones placentarias, y el espesor, diámetro, volumen y peso de la placenta, con el tipo de plancenta (p< 0,01). Conclusiones: Son más frecuentes las placentas dicoriónicas y estas tienen menos malformaciones; existe relación entre el bajo peso del recién nacido y la presencia de calcificaciones placentarias, así como entre el espesor, diámetro, volumen y peso de la placenta, con el tipo de placenta(AU)

Introduction: Placental dysfunction can originate fetal complications, intrauterine growth restriction and maternal complications, such as preeclampsia. Objective: To identify the morphometric pattern of twin placentas and its relationship with chorionicity, newborn weight and placental malformations. Methods: A descriptive study was carried out in a sample of 16 pregnant women with twin pregnancy, 25 placentas and 32 newborns. The variables placental malformations, type of placenta, presence of calcifications, newborn weight, placental weight, placental volume, placental diameter and placental thickness were studied; the association of newborn weight with the type of placenta and the presence of calcifications, placental malformations, as well as thickness, diameter, volume and weight, with the type of placenta was determined. Results: There was a higher frequency of newborns with monochorionic placentas (60 percent) without the association being statistically significant; placental malformations were significantly related to placenta type, as well as newborn weight and the presence of placental calcifications, and placental thickness, diameter, volume and weight, with placenta type (p< 0.01). Conclusions: Dichorionic placentas are more frequent and these have fewer malformations; there is a relationship between low newborn weight and the presence of placental calcifications, as well as between placental thickness, diameter, volume and weight, with the type of placenta(AU)

Flexible Video Fetoscopy: Feasibility and Outcomes of a Novel Modality for Laser Therapy in Twin-to-Twin Transfusion Syndrome Presenting with Inaccessible Anterior Placenta.

INTRODUCTION: Identification of intertwin anastomosis may be challenging during fetoscopy in cases with complete anterior placenta. The aim of this study was to describe the technique, feasibility, and outcomes of flexible video fetoscopy for laser coagulation in monochorionic (MC) twin pregnancies with twin-to-twin transfusion syndrome (TTTS) presenting with inaccessible anterior placenta. METHODS: From April 2021 to March 2022, a prospective cohort of consecutive MC twin pregnancies complicated with TTTS presenting with anterior placenta after 20 weeks was recruited. Cases with inaccessible anterior placenta during standard technique were converted into flexible video fetoscopy for completion of laser coagulation of placental anastomoses using a 270° flexible video endoscope through the same uterine port. Descriptive analysis includes feasibility, remaining anastomoses requiring laser photocoagulation, and perinatal outcomes. RESULTS: A total of 45 pregnancies with TTTS were treated with fetoscopic laser therapy during the 1-year study period. Twenty-one pregnancies presented with anterior placenta after 20 weeks, in which an inaccessible vascular equator was observed in 33.3% (7/21). Flexible video fetoscopy was successfully performed in all 7 cases at a median gestational age of 22+2 (20+0-27+1) weeks+days. Visualization of the entire placental surface, coagulation of selected vessels, and exploration of the entire vascular equator were achieved in all cases. Six cases (85.7%) required additional laser coagulation due to either vascular patency despite initial coagulation with conventional fetoscopy (1/6, 16.7%) and/or remaining noncoagulated anastomoses (5/6, 83.3%). Perinatal survival of at least one twin and both twins was achieved in 85.7% and 57.1%, respectively. DISCUSSION: Flexible video fetoscopy for completion of laser coagulation of placental anastomoses is feasible and represents a good option for TTTS cases presenting after 20 weeks with inaccessible anterior placenta.

The First Case of Fetus in Fetu in Nicaragua: The Management Experience of the Pediatric Neurosurgery Team.

Fetus in fetu (FIF) is a rare congenital anomaly of asymmetric monozygotic twins, where the parasitic twin develops abnormally inside the body of the host twin. In most cases, it is incorporated into the sibling's abdomen, which frequently presents as a retroperitoneal mass. Currently, at least 200 cases have been reported worldwide, being this the first case in Nicaragua. We describe a case of a male newborn, born via cesarean section, with a history of multiple congenital malformations observed via ultrasound examination. At birth, a mass is observed on its dorsum that impresses a skull, but without the presence of bones, with three limbs, two upper and one lower, with an outline located transversely on the pelvic girdle and the presence of two male genitalia with agenesis of the testicles and an accessory kidney. A preoperative diagnosis of FIF and spinal dysraphism was made by computed tomography (CT) and magnetic resonance imaging (MRI). They shared a spinal cord and had the presence of an open spinal defect type meningocele with aberrant roots. After the diagnosis and discussion, the multidisciplinary team proceeded to surgery to perform the separation of the twin (FIF). The subsequent anatomopathological examination revealed that the fetus was anencephalic and had reliable FIF characteristics. The resection was performed followed by the closure of the 430 mL meningocele and complete separation of the spine and the parasitic twin. We present the first case of fetus in fetu in Nicaragua.