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At least 145 records · Page 8Linked to original sources
PubMed2004

Twin-twin transfusion syndrome: a review of treatment option.

OBJECTIVE: The twin-twin transfusion syndrome (TTTS) is a complication of monozygotic-monochorionic twinning and is a direct result of transplacental communication between the circulations of twins. When acute TTTS occurs in the second trimester, the perinatal mortality can be as high as 95% in the absence of treatment. For this reason, several aggressive, even desperate treatment modalities have been attempted including selective fetocide, umbilical cord ligation, maternal digoxin therapy. None have gained wide acceptance. Serial drainage amniocentesis or amnioreduction is actually the most widely used therapy. More recently, laser ablation under fetoscopic guidance of placental vessel has been reported in an attempt to improve survival. The objective of this review was to evaluate the impact of treatment modalities in TTTS. STUDY DESIGN: Reports of prospective and retrospective trials and other study designs in English identified from searches of MEDLINE, EMBASE, specialized databases, bibliographies of review articles. Study on twin pregnancies affected by TTTS between 1990 and 2003 that met our inclusion criteria were included. RESULTS AND CONCLUSIONS: No single therapy is associated with a uniformly improved outcome for the involved twins and success is primarily related to gestational age and severity at diagnosis. Standard therapy has commonly been serial amnioreduction, which appears to improve the overall outcome. Intertwin sepstostomy similary improves outcome but has no survival advantage over serial amnioreduction. Selective fetoscopic laser photocoagualtion has emerged as an alternative treatment strategy in TTTS with at least comparable if not superior survival to serial amnioreduction. TTTS diagnosed before 26 weeks' gestation has significantly better survival rates and fewer neurological sequelae after laser therapy than amnioreduction.

Amnion↗
PubMed2006

[Actual treatment options of twin-to-twin transfusion syndrome].

Twin-to-twin transfusion syndrome -TTTS is observed in 10-15% of monochorionic twin pregnancies. The pathogenesis of the syndrome is still unknown, and the mortality reaches 80-90% if not treated. There are two invasive treatment options of TTTS: Fetoscopic laser coagulation of the placental anastomoses and serial amniodrainages. Endoscopic laser coagulation of anastomoses is a more effective first-line treatment than serial amnioreduction for severe TTTS. The rate of major neurologic complications is higher in amnioreduction group, than in Fetoscopic group.

Arteriovenous Anastomosis↗
PubMed1988

[Prenatal diagnosis of congenital anomalies--present status and future problems].

Technical advances continue to expand the number of genetic disorders that can be diagnosed in utero. The current methods for prenatal diagnosis are as follows: Amniocentesis, fetoscopy, fetal blood sampling, biopsy of fetal skin, and chorionic villus sampling (CVS). The method for growing fetal cells obtained by amniocentesis in short term culture and karyotyping has opened a new area to chromosomal anomalies. By using cultured amniotic fluid cells in larger numbers, it is also possible to diagnose many metabolic disorders. Fetoscopy has been developed which permits the perinatologist to enter the uterus and obtain tissue sample or to actually view the fetus. However, it is very difficult to visualize the fetus directly through fetoscope. Only specific parts of the fetus can be readily identified, but a total examination of surface anatomy is rarely possible. Now ultrasonography with improved resolution can clearly define many major anatomical abnormalities without apparent risk. And also, fetal blood sampling and skin biopsy have been successfully performed under ultrasound guidance rather than under direct fetoscopic visualization. Recently, the advent of fetal blood sampling has made it possible to diagnose genetic disorders which have hitherto been impossible to recognize in the fetus. The main applications are for the prenatal diagnosis of the fetal infection, coagulopathies, hemoglobinopathies, and muscular dystrophies. Several severe genodermatoses result in early death or are associated with significant morbidity. Some of these disorders can be diagnosed in utero with skin biopsies. Harlequin Ichthyosis is a typical case. A positive prenatal diagnosis of Harlequin Ichthyosis was reported.(ABSTRACT TRUNCATED AT 250 WORDS)

Amniocentesis↗
PubMed1987

Clinical aspects of fetal heart auscultation.

The widespread belief that fetal heart tones are first detected with an unamplified fetoscope at about 20 weeks' gestation has been studied prospectively only twice. Using data collection prospectively from 352 visits of 77 patients between 15 and 23 weeks' pregnancy, we studied various clinical aspects of fetal heart tone detection. We determined the gestational age at the time of initial auscultation of fetal heart tones with an ordinary fetoscope, and its relationship to quickening, parity, and placenta location. Fetal heart tones were first identified by auscultation at a mean gestational age of 19.4 weeks (range 17-22 weeks). Detection was possible in 81% of patients examined at 20 weeks and in virtually all patients examined at 21 weeks or later. Once heard, fetal heart tones were identified in every subsequent visit for all patients. Parity and placenta location were significant factors influencing initial fetal heart tone detection. Auscultation preceded quickening in only 12% of patients. Recommendations for using initial fetal heart tone detection in clinical practice are given.

Female↗
PubMed1980

Prenatal diagnosis of hemophilia B by an immunoradiometric assay of factor IX.

An immunoradiometric assay of factor IX was developed based on homologous antibodies that arose in a hemophilic patient. With this assay, 11 of 12 patients with severe hemophilia B had factor IX antigen levels below 1 U/dl and 6 patients with mild hemophilia B had various levels. Factor IX antigen in 8 fetuses (16th-20th gestational week) aborted for therapeutic reasons ranged from 1.8 to 10.0 U/dl. Six amniotic fluids contained 0.28-1.2 U/dl factor IX antigen. Using the immunoradiometric assay, we could diagnose hemophilia B prenatally in one fetus at risk. No factor IX antigen (< 0.2 U/dl) was detectable in the fetoscopic sample. After termination of the pregnancy, analysis of blood from the abortus confirmed the diagnosis of severe hemophilia B. We conclude that very sensitive immunologic assays, such as the one described here, will prove useful in prenatal diagnosis of severe hemophilia B, since determination of factor IX activity in fetoscopic samples is unrealiable because of possible contamination with thromboplastic material.

Dose-Response Relationship, Immunologic↗
PubMed1997

Operative fetoscopy: new perspective in fetal therapy?

In a limited number of conditions in utero surgery may be life-saving, such as some cases of congenital diaphragmatic hernia, cystic adenomatoid malformation of the lung, sacrococcygeal teratoma and lower urinary tract obstruction. Postoperative premature labour and its extreme invasiveness have been major drawbacks for open fetal surgery. More recently the merger of fetoscopy and advanced video-endoscopic surgery has been the basis of the concept of endoscopic fetal surgery. In order to evaluate the opportunities of 'fetendo' surgery, animal models have been developed to test the safety of the endoscopic approach, and the feasibility of surgical manipulations on the fetus. In the non-human primate, a lesser invasiveness of endoscopy over open surgical approach was demonstrated, by a significant decrease in uterine activity in comparison with hysterotomy. The main application of fetoscopy today is the surgical treatment of complicated or abnormal monochorionic twin gestations. Fetoscopic laser coagulation of chorionic plate vessels is suggested as a causal therapy for severe feto-fetal transfusion syndrome. Survival rates are around 55 per cent with an incidence of five per cent of neurological morbidity. Fetoscopic cord ligation is associated with a 66 per cent survival rate, but unfortunately also with a risk of 30 per cent for PPROM prior to 32 weeks. Although still in its early experimental phase, endoscopy seems to offer new hope for surgical fetal therapy. Though conceptually very tempting, the development of endoscopic fetal surgery should follow the formal guidelines, as earlier formulated for open surgery by the International Fetal Medicine and Surgery Society. The prospective registration of worldwide experience is advocated and a randomized trial of laser therapy versus amniodrainage is announced.

Animals↗
PubMedDate not supplied

A comparison of two time intervals for the ausculated acceleration test.

OBJECTIVE: Interest in an inexpensive, easy-to-administer antenatal screening test that did not rely on the use of electronic fetal monitoring led to development of the fetoscope administered auscultated acceleration test (AAT) in the late 1980s. More recent efforts have been directed toward providing those who may use the AAT with important information about the most effective and clinically appropriate AAT procedures. The purpose of this study was to determine the screening test validity performance of two AAT time intervals--6 minutes and 10 minutes. METHODS: Two auscultated acceleration tests (AAT6 and AAT10) were simultaneously performed using different time intervals on 205 women with high-risk pregnancies undergoing simultaneous nonstress tests (NSTS) who were referred to a tertiary care unit for antepartum testing. Standard measurements of screening test validity were calculated for each test in the prediction of selected perinatal outcomes. NST findings were included for comparative purposes. RESULTS: The AAT6 yielded an overall higher specificity as compared with the AAT10 at the expense of a slightly lower sensitivity for most perinatal outcomes; these differences were not significant at the .05 level. Relative risk ratios were similar for the AAT6 and AAT10 for both fetal distress and neonatal morbidity, with both AAT being a more effective predictor of neonatal morbidity than for fetal distress. Both tests yielded better sensitivity when compared with NST. CONCLUSIONS: Even though there was a nonsignificant trend toward higher sensitivities and lower specificities for the 10-minute AAT, this study showed that the differences in prediction of perinatal outcomes between the 6-minute and 10-minute AAT were minimal. In view of the added labor required for the 10-minute AAT in the absence of enhanced screening test validity, the 6-minute AAT is clinically preferred. This study has prompted new research questions for the continued development of the AAT as a low-technology fetal assessment technique with potential usefulness by midwives and their colleagues in a variety of settings worldwide.

Female↗
PubMedDate not supplied

Molecular and fetal tissue biopsy capabilities are needed to maximize prenatal diagnosis of junctional epidermolysis bullosa: fetal skin biopsy using a 1-mm microendoscope.

OBJECTIVE: To describe a minimally invasive micro-endoscopic technique for fetal skin biopsy and direct examination for a lethal skin condition. MATERIALS AND METHODS: Direct fetoscopic examination of a fetus was undertaken along with full thickness skin biopsies at 19 weeks' gestation. RESULTS: No phenotypic expressions of the lethal condition were visualized and six full thickness skin biopsies were collected. Pathological examination revealed normal skin structures not consistent with junctional epidermolysis bullosa (JEB). CONCLUSION: Minimally invasive examination with the 1 mm endoscope allows direct fetal phenotypic evaluation, full thickness skin biopsies, with risks similar to amniocentesis.

Adult↗
PubMed1983

Development of a nonhuman primate model for fetoscopy.

Twenty-four fetoscopy procedures were performed on 22 monkeys (19 Macaca mulatta, one M. fascicularis, two Erythrocebus patas) with gestational ages ranging from 66 to 145 days. Insertion of the fetoscope without ultrasound guidance was easy in 14 and difficult in ten procedures. Amniotic fluid exchange with normal saline, to improve visualization, was successful in eight of 13 procedures. Fetal blood sampling was successful in four of nine attempts. Nine monkeys aborted within 17 days of the fetoscopy, the remaining 13 went to term or were used in other research protocols. Major complications included maternal hemorrhage into the amniotic fluid, inability to enter the amniotic cavity, and abortion. Maternal serum alpha-fetoprotein following fetoscopy was not a useful indicator of subsequent abortion.

Abortion, Spontaneous↗
PubMed1984

Direct-vision chorionic villi biopsy for prenatal diagnosis in the first trimester.

A technique for chorionic biopsy under direct vision has been developed. It involves the transcervical insertion of a fetoscope into the extraamniotic space during continuous saline infusion. With this technique, not only is contamination with maternal tissue easily avoided, but it is even possible to select by direct vision just those villi considered most suitable for cultivation in vitro--i.e., villi rich in blood vessels and with an abundance of surface buds. As of November 1983 the technique had been used for diagnosis in 21 cases. In 19 pregnancies allowed to continue after sampling there was one fetal loss, and one woman gave birth to a healthy infant in the 39th week.

Biopsy↗
PubMed1993

Embryoscopy and fetoscopy.

The introduction of transabdominal fiberoptic thin-gauge visualization of the embryo or fetus in the first trimester allows an earlier diagnosis of congenital anomalies currently beyond the resolution of ultrasound. In addition, it has the true potential of providing access to the fetal circulation at an early age, an accomplishment that would have enormous diagnostic and therapeutic implications. In the second and third trimester, operative fetoscopic techniques promise to open a new frontier in the diagnosis and management of fetal surgical and medical conditions.

Female↗
PubMed1999

Time-related cotyledonary effects of laser coagulation of superficial chorionic vessels in an ovine model.

Endoscopic Nd:YAG laser coagulation of superficial chorionic plate vessels has been suggested as a 'causal' therapy for severe twin-to-twin transfusion syndrome (TTS), as it is believed to arrest flow over vascular anastomoses. The therapy remains debated, partly because it is questioned whether coagulation of superficial chorionic vessels can arrest blood flow over deeply located anastomoses. The latter are believed to be responsible for the majority of cases of severe TTs. In this study, the coagulation performance, and the immediate and delayed tissue effects of laser coagulation were evaluated in an in vivo ovine model. Eight pregnant ewes of about 100 days' gestational age (term= 145 days) were studied. In utero coagulation was done through a 1.2 mm fetoscope loaded with a 600 microm laser fibre, connected to an Nd:YAG laser in continuous mode. Superficial cotyledonary vessels were coagulated under visual control at a distance of 1 cm with a mean power of 60 watts. 31 lasered cotyledons were harvested, either immediately (n= 15), 14 days (n = 8) or 42 days (n = 8) after the surgery and evaluated by inspection and histology. Control cotyledons were either neighbouring cotyledons from the same amniotic sac (internal control) or cotyledons from another gestational-age-matched sac (external control). Immediate effects consisted of localized coagulation necrosis at the zone of laser impact with no significant histological effect at more than 2 mm distance, except tissue congestion. Long-term effects consisted of fibrosis without any vascular recanalization or tissue regeneration extending from the impact site over the whole cotyledon. All treated cotyledons underwent complete infarction over time. This study provides experimental evidence supporting that laser coagulation of superficial chorionic vessels entering a cotyledon achieves complete functional elimination of the involved cotyledon.

Animals↗
PubMedDate not supplied

Diamnionic monochorionic twin gestations: an overview.

Monochorionic (MC) twins account for about 20-30% of all twins, but contribute disproportionately to mortality, intrauterine growth restriction, and preterm delivery compared with dichorionic (DC) twins. This higher mortality in MC twins is likely due to the effects of placental morphologic characteristics, which include complex vascular communications between the twins associated with twin-twin transfusion syndrome (TTTS), and the tendency for the common placenta to be shared either symmetrically or asymmetrically. In assessment of clinical outcomes for TTTS, artery to vein anastomoses in the absence of artery to artery or vein to vein, especially if present with placental asymmetry, carry the worse prognosis. Chorion status in twins forms the basis for clinical risk assessment and can be determined by 7 menstrual weeks using transvaginal sonography. The variable results reported in the literature for intertwin umbilical artery Doppler findings in MC twins may be explained by differences between sonographic and clinical criteria (including differential hemoglobin concentrations) reported by various investigators. Antenatal fetal Doppler assessment of the umbilical artery and cerebral arteries can help distinguish between TTTS and placental insufficiency in MC twins. Significant restriction of fetal growth occurs in about 25% of multiple gestations, accounting for about 17% of all growth-retarded infants. Redistribution of fetal blood (brain-sparing effect), as determined by Doppler interrogation of fetal cerebral and umbilical arteries, occurs more commonly in MC twins compared to DC twins and in growth-restricted MC twins compared to nongrowth-restricted MC twins. Overall, the prognosis is poorer for the donor twins in TTTS and there is a greater prenatal death rate for the donor (18-35%), and a higher overall survival rate for recipients following fetoscopic laser treatment. Finally, the clinical and sonographic findings suggest that the polyhydramnios/oligohydramnios sequence seen in MC twins likely represents a spectrum strongly linked to placental variables.

Amnion↗
PubMed1984

Prenatal diagnosis of chronic granulomatous disease.

A luminol enhanced chemiluminescence micromethod has been adapted for use in prenatal diagnosis of chronic granulomatous disease (CGD). After validation of the assay in normal adults, newborns, fetuses, CGD carriers, and CGD patients, the fetuses of two pregnant CGD carriers were tested after fetoscopic aspiration of fetal blood. Normal neutrophil chemiluminescence and nitroblue tetrazolium slide tests were followed by delivery of two healthy infants whose normality was confirmed. Amniocytes proved useless for the prenatal diagnosis of CGD. They were found to have negligible nitroblue tetrazolium reduction, oxygen metabolism, and oxygen dependence.

Adult↗
PubMed2005

Management of fetofetal transfusion syndrome.

Feto-fetal transfusion syndrome contributes heavily to high rates of perinatal mortality and morbidity in monochorionic multiple pregnancies. Its prenatal management has been controversial for at least 25 years. We review the recent literature in order to present the basis for a pragmatic reappraisal of the management of this condition. Laser surgery of the chorionic plate inter-twin anastomoses is the best first-line treatment when the syndrome develops before 26 weeks' gestation. Survival (including quality of survival) and gestational age at delivery are improved when compared to serial amnioreduction. Second-line treatment options include repeat-laser, intra-uterine blood transfusion, serial amnioreduction, selective feticide using bipolar cord coagulation or elective delivery, depending upon gestational age and the severity of the disease and its complications. We have found that fetoscopic placental surgery has proven itself over simplicity of amnioreduction. There is no evidence that treatment should be customized according to the stage of the disease at diagnosis. Early recognition of the syndrome through fortnightly serial ultrasound follow-up of all monochorionic pregnancies should ensure timely referral and make up for geographical constraints. Laser surgery should now be available in fetal medicine units that are managing at least 20 cases per year.

Decision Trees↗
PubMed2005

Successful selective termination at 17 weeks' gestation in monochorionic monoamniotic twin pregnancy affected by twin-twin transfusion syndrome and discordant for hypoplastic left heart syndrome.

OBJECTIVES: To report a successful selective feticide in a complicated monochorionic monoamniotic (MCMA) pregnancy. METHODS: A case of MCMA pregnancy with severe twin-twin transfusion syndrome and discordant for hypoplastic left heart syndrome was diagnosed at 16 weeks' gestation. A complete ultrasound and fetoscopic surveillance was performed, ruling out cord entanglement and, thus, precluding the necessity of transecting the cord. RESULTS: The selective feticide was successfully performed by bipolar coagulation of the umbilical cord of the abnormal fetus under ultrasound guidance. The survivor twin developed normally during the rest of the pregnancy and was born at term. At 6 months of age, the infant was healthy. CONCLUSION: Selective feticide in complicated monoamniotic pregnancies can be safely performed. Cord entanglement can be confidently excluded by both ultrasound and fetoscopy, thus making the systematic transection of the umbilical cord unnecessary.

Adult↗
PubMed1983

Routine chromosome analysis on fetal blood microaliquots obtained at fetoscopy.

A routine study of the fetal karyotype was performed on samples obtained at 64 fetoscopic procedures. In 13 cases only pure amniotic fluid was available for the cultures, while in the remaining 51 cases the chromosome analysis was carried out on PHA-stimulated lymphocyte microcultures set up with any excess fetal blood above the requirements for globin-chain synthesis. Karyotype could be determined on fetal lymphocytes in 44 cases (86 per cent). All the fetuses were chromosomally normal. This experience shows that cytogenetic analysis using microaliquots of fetal blood is a relatively simple technique which should be introduced into routine prenatal diagnosis by fetoscopy.

Amniotic Fluid↗
PubMedDate not supplied

Prenatal diagnosis of chondroectodermal dysplasia with fetoscopy.

Chondroectodermal dysplasia (Ellis-van Creveld syndrome) has previously been diagnosed prenatally only once, using fetoscopy. We report on two consecutive pregnancies in a woman at risk of having a child with the syndrome during which fetoscopic visualization was performed. Ellis-van Creveld syndrome was diagnosed prenatally in one instance, while it could be excluded in the other one. Non-invasive prenatal diagnosis of the syndrome is discussed.

Adult↗