Novel autopsy and genetic findings in an acardiac twin: case report and literature review.

Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic twinning whereby a donor twin perfuses an acardiac twin via aberrant vascular anastomoses. The resulting paradoxical retrograde blood flow supplying the acardiac twin is oxygen-poor, leading to some of the most severe malformations encountered in humans. Though the first descriptions of acardiac twins date back to at least the 16th century, the pathophysiologic processes which underpin the development of TRAP sequence are still being elucidated. Theories on the pathogenesis of TRAP sequence include deficiencies intrinsic to the embryo and primary abnormalities of the placental vasculature. Autopsy studies continue to provide clues to the underlying pathogenesis of TRAP sequence, and the characterization of the spectrum of manifestations that can be observed in acardiac twins. Herein, we present the clinical, autopsy, and molecular findings in a unique case of TRAP sequence. Novel findings include a primitive cloaca-like structure and chromosomal aberrations involving 6q11.1 and 15q25.1.

Consensus protocol for management of early and late twin-twin transfusion syndrome: Delphi study.

OBJECTIVE: Fetoscopic laser photocoagulation (FLP) is a well-established treatment for twin-twin transfusion syndrome (TTTS) between 16 and 26 weeks' gestation. High-quality evidence and guidelines regarding the optimal clinical management of very early (prior to 16 weeks), early (between 16 and 18 weeks) and late (after 26 weeks) TTTS are lacking. The aim of this study was to construct a structured expert-based clinical consensus for the management of early and late TTTS. METHODS: A Delphi procedure was conducted among an international panel of experts. Participants were chosen based on their clinical expertise, affiliation and relevant publications. A four-round Delphi survey was conducted using an online platform and responses were collected anonymously. In the first round, a core group of experts was asked to answer open-ended questions regarding the indications, timing and modes of treatment for early and late TTTS. In the second and third rounds, participants were asked to grade each statement on a Likert scale (1, completely disagree; 5, completely agree) and to add any suggestions or modifications. At the end of each round, the median score for each statement was calculated. Statements with a median grade of 5 without suggestions for change were accepted as the consensus. Statements with a median grade of 3 or less were excluded from the Delphi process. Statements with a median grade of 4 were modified according to suggestions and reconsidered in the next round. In the last round, participants were asked to agree or disagree with the statements, and those with more than 70% agreement without suggestions for change were considered the consensus. RESULTS: A total of 122 experts met the inclusion criteria and were invited to participate, of whom 53 (43.4%) agreed to take part in the study. Of those, 75.5% completed all four rounds. A consensus on the optimal management of early and late TTTS was obtained. FLP can be offered as early as 15 weeks' gestation for selected cases, and can be considered up to 28 weeks. Between 16 and 18 weeks, management should be tailored according to Doppler findings. CONCLUSIONS: A consensus-based treatment protocol for early and late TTTS was agreed upon by a panel of experts. This protocol should be modified at the discretion of the operator, according to their experience and the specific demands of each case. This should advance the quality of future studies, guide clinical practice and improve patient care. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Novel autopsy and genetic findings in an acardiac twin: case report and literature review

ABSTRACT Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic twinning whereby a donor twin perfuses an acardiac twin via aberrant vascular anastomoses. The resulting paradoxical retrograde blood flow supplying the acardiac twin is oxygen-poor, leading to some of the most severe malformations encountered in humans. Though the first descriptions of acardiac twins date back to at least the 16th century, the pathophysiologic processes which underpin the development of TRAP sequence are still being elucidated. Theories on the pathogenesis of TRAP sequence include deficiencies intrinsic to the embryo and primary abnormalities of the placental vasculature. Autopsy studies continue to provide clues to the underlying pathogenesis of TRAP sequence, and the characterization of the spectrum of manifestations that can be observed in acardiac twins. Herein, we present the clinical, autopsy, and molecular findings in a unique case of TRAP sequence. Novel findings include a primitive cloaca-like structure and chromosomal aberrations involving 6q11.1 and 15q25.1.

Guideline No. 440: Management of Monochorionic Twin Pregnancies.

OBJECTIVE: This guideline reviews the evidence-based management of normal and complicated monochorionic twin pregnancies. TARGET POPULATION: Women with monochorionic twin or higher order multiple pregnancies. BENEFITS, HARMS, AND COSTS: Implementation of these recommendations should improve the management of both complicated and uncomplicated monochorionic (and higher order multiple) twin pregnancies. They will help users monitor monochorionic twin pregnancies appropriately and identify and manage monochorionic twin complications optimally in a timely manner, thereby reducing perinatal morbidity and mortality. These recommendations entail more frequent ultrasound monitoring of monochorionic twins compared to dichorionic twins. EVIDENCE: Published literature was retrieved through searches of PubMed and the Cochrane Library using appropriate MeSH headings (Twins, Monozygotic; Ultrasonography, Prenatal; Placenta; Fetofetal Transfusion; Fetal Death; Fetal Growth Retardation). Results were restricted to systematic reviews, randomized controlled clinical trials, and observational studies. There were no date limits, but results were limited to English or French language materials. VALIDATION METHODS: The content and recommendations were drafted and agreed upon by the principal authors. The Board of the SOGC approved the final draft for publication. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations). INTENDED AUDIENCE: Maternal-fetal medicine specialists, obstetricians, radiologists, sonographers, family physicians, nurses, midwives, residents, and other health care providers who care for women with monochorionic twin or higher order multiple pregnancies. TWEETABLE ABSTRACT: Canadian (SOGC) guidelines for the diagnosis, ultrasound surveillance and management of monochorionic twin pregnancy complications, including TTTS, TAPS, sFGR (sIUGR), acardiac (TRAP), monoamniotic twins and intrauterine death of one MC twin. SUMMARY STATEMENTS: RECOMMENDATIONS.

Twin Anemia-Polycythemia Sequence (TAPS): From Basic Research to Clinical Practice.

Twin pregnancy is associated with an increased risk of perinatal and maternal complications, and early establishment of the chorionicity type defines this risk. In monochorionic (MC) pregnancies, the fetuses share the same placental mass and exhibit vascular anastomoses crossing the intertwin membrane, and the combination and pattern of anastomoses determine the primary clinical picture and occurrence of future complications. Twin Anemia-Polycythemia Sequence (TAPS) was first described in 2006 after fetoscopic laser surgery in twin-to-twin transfusion syndrome (TTTS) twins, and in 2007, the first spontaneous cases were reported, recognizing TAPS as an individualized vascular identity in fetofetal transfusion syndromes. There are two types of TAPS: spontaneous (3-5%) and iatrogenic or postlaser (2-16%). TAPS consists of small diameter arteriovenous anastomoses (<1 mm) and low-rate, small-caliber AA anastomoses in the absence of amniotic fluid discordances. There are certain antenatal and postnatal diagnostic criteria, which have progressively evolved over time. New, additional secondary markers have been proposed, and their reliability is being studied. The best screening protocol for TAPS in MC twins is still a matter of debate. This review provides a survey of the relevant literature on the epidemiology, vascular pathophysiology, underlying hemodynamic factors that regulate mismatched vascular connections, and diagnostic criteria of this condition. The aim is to increase awareness and knowledge about this recently identified and frequently unrecognized and misdiagnosed pathology.

A case of amniotic band syndrome after fetal reduction by radiofrequency ablation / 中华围产医学杂志

This article reported a survived case of amniotic band syndrome (ABS) following fetal reduction by radiofrequency ablation. The woman conceived monochorionic diamniotic twin pregnancy spontaneously. Prenatal ultrasound at 24 weeks of gestation indicated twin-twin transfusion syndrome (stage Ⅲ), and radiofrequency ablation for fetal reduction was successfully performed after formal consent. At 28 +6 weeks, ultrasound reexamination revealed significant edema in the left foot of the fetus, with banding around the ankle, as well as the strangulation mark and narrowing rings. Fetal ABS (ⅡB stage) was diagnosed after multidisciplinary consultation. An immediate emergency cesarean section was performed and a live male baby was born. A thin amniotic band could be seen wrapping around the left ankle of the newborn for several rounds, with obvious strangulation marks about 1 cm deep into the skin, and significant edema on the dorsum and sole of the foot, and the submalleolus area. The amniotic band was released at once, and the edema faded gradually after surgery. After a follow-up of 28 days, the lower limbs of the newborn became normal.

Comparison of Prenatal and Neonatal Outcomes of Selective Fetal Growth Restriction in Monochorionic Twin Pregnancies with or Without Twin-to-Twin Transfusion Syndrome After Radiofrequency Ablation.

Background: This study aimed to investigate and compare the prenatal and neonatal outcomes of monochorionic twin pregnancies complicated with fetal growth restriction (sFGR) with or without twin-to-twin transfusion syndrome (TTTS) after cord occlusion by radiofrequency ablation (RFA). Methods: This prospective cross-sectional study was conducted in women with monochorionic twin pregnancies of 16 to 26 weeks of gestational age (GA) in an academic hospital from 2016 to 2020. Demographic and obstetrical characteristics such as cervical length, GA of RFA and delivery, amnioreduction, cesarean section (C/S) rate, and maximum vertical pocket as well as prenatal, neonatal, and maternal outcomes were evaluated and compared between groups using Statistical Package for the Social Sciences (SPSS). Mann-Whitney U test or independent t test was used for quantitative data and Chi square test was applied for comparing qualitative variables. The significance level of tests was 0.05. Results: Totally 213 (106 sFGR and 107 TTTS+sFGR) cases were enrolled. The mean of maternal age (P=0.787), body mass index (P=0.932), gestational age at RFA (P=0.265), as well as gestational age of delivery (P=0.482), and C/S rate (P=0.124) were not significant between the two groups, but a significant difference (P<0.001) in cervical length was observed between the two groups. No significant differences were found in newborn and fetal outcomes such as fetal demise (P=0.827), PPROM (P=0.233), abortion (P=0.088), and admission to intensive care unit (P=0.822) between the groups. Conclusion: Although worse fetal and neonatal outcomes were expected in the TTTS+sFGR group after RFA, no significant difference was observed between groups.

Single fetal demise following fetoscopic ablation for twin-to-twin transfusion syndrome-cohort study, systematic review, and meta-analysis.

BACKGROUND: Several studies have assessed preoperative and operative factors associated with fetal demise after laser for TTTS, yet these findings are not completely conclusive. OBJECTIVE: This study aimed to identify risk factors for single fetal demise (recipient and donor twins) after fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome. STUDY DESIGN: We searched PubMed, Scopus, and Web of Science systematically from the inception of the database to June 2020. We conducted a systemic review on studies investigating risk factors for fetal demise (donor and/or recipient) after fetoscopic laser photocoagulation in monochorionic pregnancies complicated with twin-to-twin transfusion syndrome. Initially, we investigated the cohort of women with twin-to-twin transfusion syndrome that underwent fetoscopic laser photocoagulation at our 2 high-volume fetal centers between 2012 and 2020 to identify risk factors for donor demise and recipient demise. Furthermore, we conducted a systematic review of the literature to better characterize these factors. Among studies that met the entry criteria, multiple preoperative and operative factors were tabulated. The random-effect model was used to pool the standardized mean differences or odds ratios and corresponding 95% confidence intervals. Heterogeneity was assessed using the I2 value. RESULTS: A total of 514 pregnancies with twin-to-twin transfusion syndrome managed with fetoscopic laser photocoagulation were included in the final analysis. Following the logistic regression, factors that remained significant for donor demise were selective fetal growth restriction (odds ratio, 1.9; 95% confidence interval, 1.3-2.8; P=.001) and umbilical artery blood flow with absent or reversed end-diastolic velocity of the donor (odds ratio, 2.06; 95% confidence interval, 1.2-3.4; P=.004). A significant factor associated with recipient demise was absent or reversed a-wave in the ductus venosus of the recipient (odds ratio, 1.74; 95% confidence interval, 1.07-3.13; P=.04). Data from 23 studies and our current cohort were included. A total of 4892 pregnancies with twin-to-twin transfusion syndrome managed with fetoscopic laser photocoagulation were analyzed for risk factors for donor demise, and 4594 pregnancies with twin-to-twin transfusion syndrome were analyzed for recipient demise. Among studies, the overall incidence rates ranged from 10.9% to 35.8% for donor demise and 7.3% to 24.5% for recipient demise. Significant risk factors for donor demise were intertwin estimated fetal weight discordance of >25% (odds ratio, 1.86; 95% confidence interval, 1.44-2.4; I2, 0.0%), selective fetal growth restriction (odds ratio, 1.78; 95% confidence interval, 1.4-2.27; I2, 0.0%), twin-to-twin transfusion syndrome stage III (odds ratio, 2.18; 95% confidence interval, 1.53-3.12; I2, 0.0%), umbilical artery blood flow with absent or reversed end-diastolic velocity of the donor (odds ratio, 2.31; 95% confidence interval, 1.9-2.8; I2, 23.7%), absent or reversed a-wave in the ductus venosus of the donor (odds ratio, 1.83; 95% confidence interval, 1.45-2.3; I2, 0.0%), and presence of arterioarterial anastomoses (odds ratio, 2.81; 95% confidence interval, 1.35-5.85; I2, 90.7%). Sequential selective coagulation was protective against donor demise (odds ratio, 0.31; 95% confidence interval, 0.16-0.58; I2, 0.0%). Significant risk factors for recipient demise were twin-to-twin transfusion syndrome stage IV (odds ratio, 2.18; 95% confidence interval, 1.01-4.6; I2, 16.5%), umbilical artery blood flow with absent or reversed end-diastolic velocity of the recipient (odds ratio, 2.68; 95% confidence interval, 1.91-3.74; I2, 0.0%), absent or reversed a-wave in the ductus venosus of the recipient (odds ratio, 2.37; 95% confidence interval, 1.55-3.64; I2, 60.2%), and middle cerebral artery peak systolic velocity of >1.5 multiple of the median (odds ratio, 3.06; 95% confidence interval, 1.36-6.88; I2, 0.0%). CONCLUSION: Abnormal blood flow patterns represented by abnormal Doppler studies and low fetal weight were associated with single fetal demise in women with twin-to-twin transfusion syndrome undergoing laser therapy. Although sequential selective coagulation was protective against donor demise, the presence of arterioarterial anastomoses was considerably associated with donor demise. This meta-analysis extensively investigated the association of a wide range of preoperative and operative factors with fetal demise. These findings may be important inpatient counseling, in further understanding the disease, and perhaps in improving surgical techniques.

Twin anemia polycythemia sequence in a dichorionic diamniotic pregnancy: a case report.

Complications related to the vascular anastomosis of the placental vessels in monochorionic twins are fatal. The clinical syndromes of feto-fetal transfusion include twin anemia polycythemia sequence (TAPS), twin-twin transfusion syndrome, and twin reversed arterial perfusion sequence. We present an extremely rare case of TAPS in a dichorionic diamniotic pregnancy. A 36-year-old woman, gravida 0, para 0, was referred to our hospital with suspected preterm premature membrane rupture. Although her pelvic examination did not reveal specific findings, the non-stress test result showed minimal variability in the first fetus and late deceleration in the second one. An emergency cesarean section was performed. The placenta was fused, and one portion of the placenta was pale, while the other portion was dark red. The hemoglobin level of the first fetus was 7.8 g/dL and that of the second one was 22.2 g/dL.

Neurodevelopmental outcomes in twin-to-twin transfusion syndrome survivors at 12 months old after fetoscopic laser occlusion of chorioangiopagous vessels / 中华围产医学杂志

Objective:To investigate the risk factors for cerebral injury in survivors of twin-to-twin transfusion syndrome (TTTS) after fetoscopic laser occlusion of chorioangiopagous vessels(FLOC) and to analyze the neurodevelopmental outcomes at 12 months of corrected age.Methods:A total of 136 cases of TTTS receiving FLOC in the Third Affiliated Hospital of Zhengzhou University from May 2018 to August 2021 were retrospectively selected as the FLOC group, and the survivors were followed up. Neurological development at 12 months of corrected age was assessed using the Griffiths mental development scales-Chinese (GDS-C) from five dimensions with locomotor, personal-social, hearing and language, hand-eye coordination and performance subscales. Eighty-eight fetuses of TTTS pregnancies receiving expectant treatment or amniotic fluid reduction were selected as the non-FLOC group. The perinatal mortality and the incidence of cerebral injury in the two groups were compared, as well as the incidence of cerebral injury between patients undergoing Solomon surgery and selective laser surgery in the FLOC group. Generalized estimating equations were used to analyze the risk factors for neonatal cerebral injury after FLOC and the factors influencing general developmental quotient score at the corrected age of 12 months. Chi-square test, t-test, and Mann-Whitney U test were used for statistical analysis. Results:(1) The perinatal mortality rate in the FLOC group was lower than that in the non-FLOC group [14.7% (20/136) vs 26.1% (23/88), χ 2=4.50, P=0.034]. There was no statistical significance in the incidence of neonatal cerebral injury between the two groups [18.7% (23/123) vs 21.8% (17/78), χ 2=0.29, P=0.592], but the incidence of severe cerebral injury in the FLOC group was lower than that in the non-FLOC group [6.5% (8/123) vs 15.4% (12/78), χ 2=4.20, P=0.040]. (2) In the FLOC group, there was no significant difference in the incidence of cerebral injury between donors and recipients, or between Solomon surgery and selective laser surgery [16.4% (10/61) vs 21.0% (13/62), χ 2=0.42; 20.0% (9/45) vs 17.9% (14/78), χ 2=0.08; both P>0.05]. (3) Multivariate analysis showed that neonatal asphyxia ( OR=7.04, 95% CI: 1.45-34.20, P=0.016) and higher preoperative TTTS stage ( OR=2.05, 95% CI: 1.10-3.82, P=0.023) were risk factors for neonatal cerebral injury. (4) Fifty-two cases were successfully followed up at the corrected age of 12 months, and the incidence of developmental delay in at least one dimension was 34.6% (18/52). Developmental delay was mainly manifested in locomotor skills and language, accounting for 26.9% (14/52) and 11.5% (6/52). No significant difference in Z value was found between recipients and donors in each dimension (all P>0.05). Solomon surgery, larger gestational age at operation and low birth weight were related to low general developmental quotient score (95% CI:－11.71 to－0.23，－1.99 to－0.47，0.00-0.01，respectively，all P<0.05). Conclusions:The occurrence of cerebral injury in TTTS survivors after FLOC is related to preoperative TTTS staging and intrapartum neonatal asphyxia. Neurodevelopment of survivors is related to birth weight and gestational age at surgery, and there is a higher incidence of mild developmental delay at corrected age of 12 months.

Safety of neuraxial anesthesia in patients twin pregnancy and twin-to-twin transfusion syndrome taken to laser photocoagulation. Retrospective cohort study / Seguridad de la anestesia neuroaxial en mujeres con embarazo gemelar y síndrome de transfusión feto-fetal, sometidas a fotocoagulación láser. Estudio de cohorte retrospectiva

Objective: To describe the clinical characteristics and the frequency of maternal, fetal and neonatal complications in accordance with the neuraxial anesthesia (NA) technique in women with twin-totwin transfusion syndrome (TTTS) treated with laser photocoagulation. Materials and Methods: Descriptive retrospective cohort study of pregnant patients with TTTS treated with laser photocoagulation under NA at Fundación Valle del Lili, Cali (Colombia), between 2013-2017. Patients with Quintero stage V TTTS were excluded. The protocol was approved by the institutional ethics committee. Results: Of the participants, 32 met the inclusion and exclusion criteria. The study population consisted of young, multiparous women. Urgent interventions were performed in 87.5% of cases; 43.7% were Quintero stage III and epidural anesthesia was used in 56.2% of the women. Maternal hemodynamic variables were similar, in accordance with the timing of surgery and the neuraxial technique used. Sustained hypotension occurred in 65.6% of the pregnant women and 9.3% developed pulmonary edema. Pre-term delivery occurred in 65.6% of the patients and 18.7% had premature rupture of membranes. There were 14 fetal demises and five neonatal deaths. There were no cases of maternal mortality. Conclusions: In patients with TTTS requiring laser photocoagulation, the use of epidural, spinal or combined anesthesia is likely associated with similar maternal hemodynamic variables at the time of surgery. Practitioners providing care to these pregnant women must be aware of the frequent occurrence of maternal, fetal and neonatal complications. Prospective studies to assess the safety and effectiveness of the different neuraxial anesthesia techniques in patients with TTTS are required.

Objetivo: describir las características clínicas y la frecuencia de complicaciones maternas, fetales y neonatales, según técnica de anestesia neuroaxial (AN) en mujeres con síndrome de transfusión feto-fetal (STFF) tratadas con fotocoagulación láser (FL). Materiales y métodos: estudio de cohorte retrospectiva descriptivo. Se incluyeron gestantes con STFF tratadas con FL y AN en la Fundación Valle del Lili, Cali (Colombia) entre 2013-2017. Se excluyeron pacientes con STFF estadio-V de Quintero. Se usó estadística descriptiva. El protocolo fue aprobado por el Comité de Ética de la institución. Resultados: 32 participantes cumplieron con los criterios de inclusión y de exclusión. La población estuvo constituida por mujeres jóvenes, multíparas. En el 87,5% de los casos se realizó intervención de urgencia. El 43,7% presentaba el estadio-III de Quintero y en el 56,2 % de las gestantes se utilizó anestesia epidural. Las variables hemodinámicas maternas exhibieron un comportamiento similar, acorde al momento de la cirugía y la técnica neuoraxial implementada. El 65,6 % de las gestantes presentó hipotensión sostenida y el 9,3 % desarrolló edema pulmonar. El 65,6 % de las pacientes experimentó parto pretérmino y el 18,7 % ruptura prematura de membranas. Se registraron 14 muertes fetales y cinco neonatales. No se registraron casos de mortalidad materna. Conclusiones: en pacientes con STFF que requieren FL, el uso de la anestesia epidural, espinal o combinada probablemente se asocia con un comportamiento similar al de las variables hemodinámicas maternas, durante los momentos de la cirugía. Los profesionales que brindan atención a estas gestantes deben estar alerta ante la frecuente aparición de complicaciones maternas, fetales y neonatales. Se requieren estudios prospectivos que evalúen la seguridad y la efectividad de las diferentes técnicas de anestesia neuroaxial en pacientes con STFF.

Seguridad de la anestesia neuroaxial en mujeres con embarazo gemelar y síndrome de transfusión feto-fetal, sometidas a fotocoagulación láser. Estudio de cohorte retrospectiva / Safety of neuraxial anesthesia in patients twin pregnancy and twin-to-twin transfusion syndrome taken to laser photocoagulation. Retrospective cohort study

Objetivo: describir las características clínicas y la frecuencia de complicaciones maternas, fetales y neonatales, según técnica de anestesia neuroaxial (AN) en mujeres con síndrome de transfusión feto-fetal (STFF) tratadas con fotocoagulación láser (FL). Materiales y métodos: estudio de cohorte retrospectiva descriptivo. Se incluyeron gestantes con STFF tratadas con FL y AN en la Fundación Valle del Lili, Cali (Colombia) entre 2013-2017. Se excluyeron pacientes con STFF estadio-V de Quintero. Se usó estadística descriptiva. El protocolo fue aprobado por el Comité de Ética de la institución. Resultados: 32 participantes cumplieron con los criterios de inclusión y de exclusión. La población estuvo constituida por mujeres jóvenes, multíparas. En el 87,5% de los casos se realizó intervención de urgencia. El 43,7% presentaba el estadio-III de Quintero y en el 56,2 % de las gestantes se utilizó anestesia epidural. Las variables hemodinámicas maternas exhibieron un comportamiento similar, acorde al momento de la cirugía y la técnica neuoraxial implementada. El 65,6 % de las gestantes presentó hipotensión sostenida y el 9,3 % desarrolló edema pulmonar. El 65,6 % de las pacientes experimentó parto pretérmino y el 18,7 % ruptura prematura de membranas. Se registraron 14 muertes fetales y cinco neonatales. No se registraron casos de mortalidad materna. Conclusiones: en pacientes con STFF que requieren FL, el uso de la anestesia epidural, espinal o combinada probablemente se asocia con un comportamiento similar al de las variables hemodinámicas maternas, durante los momentos de la cirugía. Los profesionales que brindan atención a estas gestantes deben estar alerta ante la frecuente aparición de complicaciones maternas, fetales y neonatales. Se requieren estudios prospectivos que evalúen la seguridad y la efectividad de las diferentes técnicas de anestesia neuroaxial en pacientes con STFF.

Objective: To describe the clinical characteristics and the frequency of maternal, fetal and neonatal complications in accordance with the neuraxial anesthesia (NA) technique in women with twin-to- twin transfusion syndrome (TTTS) treated with laser photocoagulation. Materials and Methods: Descriptive retrospective cohort study of pregnant patients with TTTS treated with laser photocoagulation under NA at Fundación Valle del Lili, Cali (Colombia), between 2013-2017. Patients with Quintero stage VTTTS were excluded. The protocol was approved by the institutional ethics committee. Results: Of the participants, 32 met the inclusion and exclusion criteria. The study population consisted of young, multiparous women. Urgent interventions were performed in 87.5% of cases; 43.7% were Quintero stage III and epidural anesthesia was used in 56.2% of the women. Maternal hemodynamic variables were similar, in accordance with the timing of surgery and the neuraxial technique used. Sustained hypotension occurred in 65.6% of the pregnant women and 9.3% developed pulmonary edema. Pre-term delivery occurred in 65.6% of the patients and 18.7% had premature rupture of membranes. There were 14 fetal demises and five neonatal deaths. There were no cases of maternal mortality. Conclusions: In patients with TTTS requiring laser photocoagulation, the use of epidural, spinal or combined anesthesia is likely associated with similar maternal hemodynamic variables at the time of surgery. Practitioners providing care to these pregnant women must be aware of the frequent occurrence of maternal, fetal and neonatal complications. Prospective studies to assess the safety and effectiveness of the different neuraxial anesthesia techniques in patients with TTTS are required.

The Detection, Outcome, and Presentation of Twin-Twin Transfusion Syndrome in Monochorionic Diamniotic Twin Pregnancies Followed with a Protocol of Fortnightly Ultrasound Examination.

BACKGROUND: Evidence to support a fortnightly scan protocol for monochorionic diamniotic (MCDA) pregnancies to detect twin-twin transfusion syndrome (TTTS) is scarce. Also, TTTS-related mortality in an unselected cohort is not well documented. Finally, common knowledge suggests that a more frequent follow-up may pick up the disease at a milder stage, but little is known on the ultrasound findings before the diagnosis. OBJECTIVES: We examine if a fortnightly ultrasound scan from 16 weeks onward detects TTTS in time. Also, we document the outcomes in a large unselected cohort of MCDA twins and examine the ultrasound findings within 14 days before diagnosis. METHODS: Retrospective cohort of 675 MCDA twin pregnancies followed with a fortnightly scan protocol from 16 weeks onward. Timely detection of TTTS was defined as before fetal demise (stage V), ruptured membranes, or a dilated cervix. We compared the ultrasound findings before the diagnosis between stage I-II and stage III-IV. RESULTS: A total of 82/675 (12%) pregnancies developed TTTS, of which 74/82 (90%) were detected in time. In 8/82 (10%), TTTS was diagnosed in stage V: 5 before 16 weeks and 2 after 26 weeks. Fetoscopic laser photocoagulation (FLP) of the placental anastomoses was performed in 48/82 (59%). The survival of TTTS in the entire cohort was 105/164 (64%). In contrast, survival after FLP was 77/96 (80%). In 16/19 (84%) of stage III-IV TTTS, abnormal Doppler findings preceded the diagnosis of TTTS. CONCLUSIONS: A scheme of fortnightly ultrasound scans from 16 weeks onward detects 9 out of ten TTTS pregnancies in time. Most stage V cases presented outside the typical time window of 16 and 26 weeks. Survival rates after FLP underestimate the mortality of TTTS. Most stage III-IV cases have abnormal Doppler findings before the diagnosis of TTTS.

Gran feto acardio: diagnóstico tardío de gestacion gemelar monocorial biamniótica complicada por secuencia TRAP: reporte de un caso y revisión de la literatura / Great acardiac fetus: late diagnosis of monochorionic diamniotic twin pregnancy complicated by sequence TRAP: case report and review of the literature

OBJETIVOS: reportar el caso de una paciente con gestación gemelar monocorial-biamniótica complicada por secuencia TRAP que dio lugar al nacimiento de un feto bomba de 1932 gramos sin malformaciones anatómicas y de un feto acardio anceps de 1800 gramos, y realizar una revisión sobre esta patología y la importancia de su diagnóstico y tratamiento precoces. MATERIALES Y MÉTODOS: se presenta el caso de un feto acardio en una gestante con embarazo sin control estricto en el Hospital San Pedro de Logroño en el año 2019, de interés por su diagnóstico tardío y elevado peso al nacimiento del feto acardio. Se realizó una búsqueda de la literatura en las bases de datos Medline vía PubMed, OVID, Embase y SciE-LO con las palabras clave DeCS y términos MeSH. Como criterios de inclusión se consideraron artículos tipo series y reportes de casos y artículos de revisión desde enero de 1950 hasta enero de 2020. RESULTADOS: la búsqueda incluyó 39 referencias bibliográficas sobre las que se repasaron las principales cuestiones teóricas a exponer. El peso del feto acardio de nuestro caso fue muy elevado sin provocar repercusión en el feto sano, en comparación con la bibliografía, lo que aporta singularidad al caso, siendo sólo equiparable la serie de casos de Brassard et al (1999), con pesos de los fetos acardio por encima de 1700 gramos y diferenciándose en 100 gramos del feto bomba. CONCLUSIONES: el feto acardio es una complicación infrecuente de embarazos gemelares monocoriales. Se requiere la presencia de anastomosis vasculares placentarias entre ambas circulaciones. El diagnóstico precoz es importante para disminuir la morbilidad y usar, en la medida de lo posible, técnicas terapéuticas no invasivas.

OBJECTIVES: to report the case of a patient with a monochorionic-biamniotic twin gestation complicated by TRAP sequence that gave rise to the birth of a pump fetus without anatomical malformations (1932 g) and an acardiac anceps fetus (1800 g), and to review this pathology and the importance of its early diagnosis and management. MATERIAL AND METHODS: the case of an acardiac fetus is presented in a pregnant woman without strict control at the Hospital San Pedro de Logroño in 2019, worthwhile because of its late diagnosis and high birth weight. A search of the literature was carried out in the Medline databases via PubMed, OVID, Embase and SciELO with the MeSH terms. As inclusion criteria, we considered series-type articles and case reports, cohorts and review articles from January 1950 to January 2020. RESULTS: 39 bibliographic references were included with the main theoretical questions to be reviewed. Our acardiac fetus weight was very high comparing with the bibiography and without causing repercussion in the healthy fetus, which contributes to the uniqueness of the case, only the series report by Brassard et al (1999) is comparable, with weights of the acardiac fetus above 1700 grams and differing by 100 grams from the pump fetus. CONCLUSIONS: the acardiac fetus is an infrequent complication of monochorionic twin pregnancies. The presence of placental vascular anastomoses between both circulations is required. Early diagnosis is important to decrease morbidity and to use, as far as possible, non-invasive therapeutic techniques.

The prevalence of brain lesions after in utero surgery for twin-to-twin transfusion syndrome on third-trimester MRI: a retrospective cohort study.

OBJECTIVE: Due to the increased risk of antenatal brain lesions, we offer a third-trimester magnetic resonance imaging (MRI) scan to all patients who underwent an in utero intervention for twin-twin transfusion syndrome (TTTS). However, the usefulness of such a policy has not been demonstrated yet. Therefore, we determined the prevalence of antenatal brain lesions detected on third-trimester MRI and the proportion of lesions detected exclusively on MRI. MATERIALS AND METHODS: We conducted a retrospective cohort study of monochorionic diamniotic twin pregnancies complicated by TTTS that underwent laser coagulation of the vascular anastomoses or fetal reduction by umbilical cord occlusion between 2010 and 2017. We reviewed the third-trimester MRI findings and compared those with the prenatal ultrasonography. RESULTS: Of the 141 patients treated with laser coagulation and 17 managed by cord occlusion, 112/141 (79%) and 15/17 (88%) patients reached 28 weeks. Of those, 69/112 (62%) and 11/15 (73%) underwent an MRI between 28 and 32 weeks. After laser coagulation, MRI detected an antenatal brain lesion in 6 of 69 pregnancies (9%) or in 6 of 125 fetuses (5%). In 4 cases (67%), the lesion was detected only on MRI. In the 11 patients treated with cord occlusion, no brain lesions were diagnosed. CONCLUSION: The prevalence of brain lesions detected by third-trimester MRI is higher compared to prenatal ultrasonography alone, making MRI a useful adjunct to detect antenatal brain lesions in twin pregnancies after in utero treatment for TTTS. KEY POINTS: • In utero interventions for twin-to-twin transfusion syndrome (TTTS) do not prevent the occurrence of antenatal brain lesions. • Fetal magnetic resonance imaging (MRI) has high accuracy in detecting anomalies of cortical development and can be a useful adjunct to ultrasonography in diagnosing certain brain abnormalities. • After laser coagulation of the anastomoses for TTTS, third-trimester MRI diagnosed a brain lesion that was not detected earlier on ultrasound scan in 6% of pregnancies.

Twin-twin transfusion syndrome - a University Hospital experience with intrauterine treatment / Síndrome da transfusão feto-fetal - experiência de um hospital universitário com tratamento intrauterino

ABSTRACT Introduction: twin-to-twin transfusion syndrome (TTTS), defined by combination of polyhydramnios-oligohydramnios, is the most prevalent (5%-35%) of the abnormalities due to placental vascular anastomoses and the most lethal (80%-100% mortality) if untreated. Fetoscopic laser ablation of abnormal vasculature using the Solomon technique is the gold standard approach. It consists of interrupting the intertwin blood flow. Objectives: to present our initial experience at the Fetal Surgery Service of the Hospital de Clinicas of the Federal University of Parana (HC-UFPR) and to compare our results with those reported in the literature. Methods: we conducted a retrospective analysis of pregnancies who had undergone laser ablation, assessing data on Quintero's staging, gestational age at diagnosis and at the time of the procedure, placental position, immediate post-procedure survival, and survival after the neonatal period. We then compared these data with the most recent data available in the literature. Results: we analyzed ten TTTS cases. The diagnosis was performed before the 26th week of pregnancy (median 20.8 weeks) and treatment occurred in a median of 9.5 days later. The distribution by the Quintero's staging was of three cases in stage II, five in stage III, and two in stage IV. In 50% of the gestations, at least one of the fetuses survived through the neonatal period. Conclusion: the treatment of TTTS in the HC-UFPR had a positive impact in the survival of the affected fetuses, although the results were worse than the ones reported in the literature, probably due to the delay in referencing the patients to our service, leading to a prolonged interval between diagnosis and treatment.

RESUMO Introdução: a síndrome de transfusão feto-fetal (STFF), definida pela combinação polidrâmnio-oligohidrâmnio, é a mais prevalente (5 a 35%) das anormalidades associadas às anastomoses vasculares placentárias e tem a maior letalidade (80 a 100%) se não tratada. A ablação a laser destes vasos por via fetoscópica com a técnica de Solomon é o tratamento de escolha atual para a interrupção das anastomoses vasculares. Objetivo: apresentar a experiência inicial do Serviço de Cirurgia Fetal do Hospital de Clínicas da Universidade Federal do Paraná (HC-UFPR) e comparar nossos resultados com os da literatura. Métodos: foram revisados os prontuários de todas as pacientes submetidas ao procedimento de ablação a laser, sendo analisados os dados referentes ao estadiamento de Quintero, à idade gestacional ao diagnóstico e ao procedimento, à posição placentária, à sobrevida imediata pós-procedimento e sobrevida após o período neonatal. Os dados foram então comparados com os mais recentes disponíveis na literatura. Resultados: dez casos de STFF foram analisados. Todos diagnosticados antes da 26a semana (mediana 20,79) e o intervalo diagnóstico-tratamento teve mediana de 9,5 dias. A distribuição pelo estadiamento de Quintero foi: três casos no estádio II, cinco casos no III e dois casos no IV. Em 50% das gestações pelo menos um dos fetos sobreviveu ao período neonatal. Conclusão: o tratamento da STFF no HC-UFPR impactou positivamente a sobrevida dos fetos acometidos. Entretanto, nossos resultados estão aquém dos reportados na literatura, possivelmente pelo demora no referenciamento das pacientes, com intervalo aumentado entre diagnóstico e tratamento.

Pregnancy outcome and placental characteristics of twin-to-twin transfusion syndrome with different vascular patterns following fetoscopic laser surgery / 中华围产医学杂志

Objective:To evaluate the effect of different superficial vascular patterns on pregnancy outcome and residual anastomosis following laser coagulation in placentae with twin-to-twin transfusion syndrome (TTTS).Methods:This study retrospectively collected and analyzed the clinical data and postnatal placenta perfusion characteristics of 57 cases of TTTS who received fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) and delivered at Peking University Third Hospital from April 2014 to April 2019. According to the vascular pattern, all the cases are divided into four groups, which were parallel, staggered, mixed, and monoamniotic groups. Differences in the operation time and method, pregnancy outcome, and residual vascular anastomosis between the four groups were compared using analysis of variance, non-parametric tests, and Chi-square (or Fisher's exact) tests. Results:Among the 57 cases, the staggered, mixed, parallel, and monoamniotic types were accounted for 68.4%(39/57), 15.8%(19/57), 14.0%(8/57), and 1.7%(1/57), respectively. After exclusion of one case of monoamniotic type, gestational weeks at onset and surgery in the parallel group were both later than the staggered and mixed groups [23.0 (22.0-26.3) weeks vs 21.0 (17.0-24.7) weeks and 22.6 (21.3-23.9) weeks, H=10.306, P=0.006; 25.0 (22.6-26.3) weeks vs 22.0 (17.4-24.9) weeks and 23.2 (22.4-24.0) weeks, H=9.926, P=0.007; all P'<0.016 7]. There was no statistical significance in the differences in operation time and method, gestational age at the end of the pregnancy, neonatal birth weight, or birth weight discordance between the three groups. The diameter of residual vascular anastomosis of women in the staggered group was less than that in the mixed group [0.6 (0.1-5.0) mm vs 1.4 (0.3-5.1) mm, P'<0.016 7], but no significant difference was observed in the parallel-group [0.9 (0.2-3.6) mm] neither with the mixed or staggered group. The staggered group was noted for an increased distance ratio of umbilical cord insertion compared with the parallel and the mixed group [0.66 (0.59-1.00) vs 0.49 (0.25-0.55) and 0.48 (0.42-0.53); P'<0.016 7]. There was no significant difference between the parallel and the mixed groups. Conclusions:Placental superficial vascular patterns may affect the residual vascular anastomosis in women with TTTS following FLOC, which should be thoroughly evaluated before the operation to develop an individual management plan to reduce residual anastomosis incidence.

[Perioperative maternal complications of twin-twin transfusion syndrome after fetoscopic laser photocoagulation].

Objective: To analyze the perioperative maternal complications of twin-twin transfusion syndrome (TTTS) after fetolascopic laser photocoagulation (FLP). Methods: A retrospective study was conducted among 182 cases with TTTS received FLP in Shanghai First Maternity and Infant Hospital from January 2010 to December 2018. The types, incidence and related factors of perioperative maternal complications as well as the changes of maternal laboratory parameters before and after FLP were analyzed. Results: The age of 182 TTTS pregnant women was (29.8±3.9) years old, body mass index (BMI) before pregnancy was (21.3±2.9) kg/m2. The median gestational week of FLP treatment was 22.0 weeks, the preoperative cervical length was (34.1±9.0) mm, and the median preoperative maximum vertical pocket was 12.0 cm. During the perioperative period of FLP treatment, 22 cases (12.1%, 22/182) presented maternal complications, among which 4 cases (2.2%, 4/182) presented severe postoperative maternal complications, including 3 cases of pulmonary edema and 1 case of pulmonary embolism accompanied with right cardiac insufficiency. There were 18 cases (9.9%, 18/182) of common maternal complications during the perioperative period, including 6 cases (3.3%, 6/182) of intraoperative hemorrhage, 5 cases (2.7%, 5/182) of intraoperative amniotic fluid leakage into the pelvic cavity, 5 cases (2.7%, 5/182) of premature rupture of membrane 72 hours after the operation, 1 case (0.5%, 1/182) of inevitable abortion, and 1 case (0.5%, 1/182) of infection. The analysis of related risk factors found that maternal complications were only related to BMI before pregnancy, and the BMI of TTTS pregnant women with complications was lower than that of those without complications, the difference was statistically significant (P<0.01). The hemoglobin level, hematocrit and albumin level of TTTS pregnant women were significantly decreased at 4-6 hours and 24 hours after FLP respectively, compared with those before surgery (P<0.01), and there were no significant correlations with the amount of amniodrainage during surgery (P>0.05 for all). Conclusions: The overall incidence of perioperative maternal complications in the treatment of TTTS by FLP is not high, among which the serious complications mainly include pulmonary edema and pulmonary embolism. Timely correction of maternal hemodilution that may occur in TTTS pregnant women could achieve a good prognosis after FLP.

Fetal therapies as standard prenatal care in Japan.

With recent advances in fetal medicine, various attempts have been made to save fetuses facing perinatal death or devastating consequences despite optimal management after birth. The concept of the fetus as a patient has been established through the application of in utero treatments. This paper reviews fetal therapies in order to highlight the role of perinatal medicine as standard prenatal care. Fetal therapies consist of medical therapy, percutaneous ultrasound-guided surgery, fetoscopic surgery, and open fetal surgery. In the 1980s, with advances in ultrasound imaging, percutaneous ultrasound-guided surgeries such as vesicoamniotic shunting for lower urinary tract obstruction and thoracoamniotic shunting (TAS) for fetal hydrothorax (FHT) were started. In the 1990s, fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS) was introduced, and later, a fetoscopic approach for congenital diaphragmatic hernia was also established. The revival of open fetal surgery, introduced in the 1980s by pediatric surgeons, began in the 2010s after a successful clinical study for myelomeningocele. Although many fetal therapies are still considered experimental, some have proven effective, such as FLS for TTTS, TAS for primary FHT, and radiofrequency ablation (RFA) for twin reversed arterial perfusion (TRAP) sequence. These three fetal therapies have been approved for coverage by Japan National Health Insurance as a result of clinical studies performed in Japan. FLS for TTTS, TAS for primary FHT, and RFA for TRAP sequence have become standard prenatal care approaches in Japan. These three minimally invasive fetal therapies will help improve the perinatal outcomes of fetuses with these disorders.

Fetal therapies as standard prenatal care in Japan

With recent advances in fetal medicine, various attempts have been made to save fetuses facing perinatal death or devastating consequences despite optimal management after birth. The concept of the fetus as a patient has been established through the application of in utero treatments. This paper reviews fetal therapies in order to highlight the role of perinatal medicine as standard prenatal care. Fetal therapies consist of medical therapy, percutaneous ultrasound-guided surgery, fetoscopic surgery, and open fetal surgery. In the 1980s, with advances in ultrasound imaging, percutaneous ultrasound-guided surgeries such as vesicoamniotic shunting for lower urinary tract obstruction and thoracoamniotic shunting (TAS) for fetal hydrothorax (FHT) were started. In the 1990s, fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS) was introduced, and later, a fetoscopic approach for congenital diaphragmatic hernia was also established. The revival of open fetal surgery, introduced in the 1980s by pediatric surgeons, began in the 2010s after a successful clinical study for myelomeningocele. Although many fetal therapies are still considered experimental, some have proven effective, such as FLS for TTTS, TAS for primary FHT, and radiofrequency ablation (RFA) for twin reversed arterial perfusion (TRAP) sequence. These three fetal therapies have been approved for coverage by Japan National Health Insurance as a result of clinical studies performed in Japan. FLS for TTTS, TAS for primary FHT, and RFA for TRAP sequence have become standard prenatal care approaches in Japan. These three minimally invasive fetal therapies will help improve the perinatal outcomes of fetuses with these disorders.