Ultrasound findings in Pseudoamniotic band syndrome after fetoscopic surgery: Antenatal description of three cases and review of literature.

INTRODUCTION: Pseudoamniotic Bands Syndrome (PABS) was described as iatrogenic complication from in utero procedure as fetoscopy. OBJECTIVE: The aim of our study was to identify the ultrasound findings in PABS diagnosed prenatally METHODS: First, we reported cases of PABS following fetoscopic surgery that were diagnosed prenatally in our institution. We collected all ultrasound data with fetal and neonatal issues. Then, a literature review was conducted by searching the Medline and Cochrane Library computer databases until 2020 to find publications that involve PABS diagnosed prenatally or postnatally. The following keywords were selected and combined: "pseudoamniotic bands syndrome", "fetoscopy", "fetal surgery". RESULTS: We collected three cases of PABS diagnosed prenatally in our center following fetoscopic procedures for complicated monochorionic pregnancies. Among these cases, we reported the following ultrasound findings: floating membrane, amniotic bands, striction of limbs, perilesional edema, reduced member size and anomalies of Doppler flow. Including our cases, we reported 23 published PABS of which eight (35%) were prenatally diagnosed. When it was diagnosed, mean GA at PABS diagnosis was 23 weeks (mean interval from fetoscopic to diagnosis was 4 weeks). Three fetoscopic release of amniotic bands were described. The principal parts affected were the limbs, more particularly the extremities. CONCLUSION: PABS was accessible to an antenatal diagnosis, as well as ABS. Although it is a rare complication of fetoscopic surgery, ultrasound examinations after procedure should focus on PABS signs to improve prognosis of the neonates.

Effects and outcomes of septostomy in twin-to-twin transfusion syndrome after fetoscopic laser therapy.

BACKGROUND: To evaluate the incidence and outcomes of septostomy in twin-to-twin transfusion syndrome (TTTS) after fetoscopic laser therapy. METHODS: A retrospective analysis of TTTS postlaser septostomy between 2005 and 2018 was performed. Postlaser septostomy was diagnosed using both (1) a free-floating intertwin membrane flap visible on ultrasound examination and (2) the rapid equalization of amniotic fluid maximum vertical pocket in the donor and recipient amniotic sacs observed after laser therapy. Perinatal survival, neonatal brain image anomaly, gestational age at operation and birth, incidence of premature rupture of membranes (PROM) within 3 weeks after operation, pseudoamniotic band syndrome, and cord entanglement were evaluated. RESULTS: In the 159 TTTS cases included, 12 had postlaser septostomy. Relative to the group without septostomy, the septostomy group had a lower total fetal survival rate (54.2% vs 73.6%, p = 0.041), an earlier mean gestational age at delivery (27.8 vs 34.4 weeks, p = 0.009), a higher risk of PROMs within 3 weeks after operation (33.3% vs 5.4%, p = 0.004), a higher cord entanglement rate (16.7% vs 0%, p = 0.005), and a higher brain image anomaly rate (23.0% [3/13] vs 5.0% [11/218], p = 0.035). After considering the severe Quintero stages (stage III and IV), postlaser septostomy was the only variable [p = 0.003, odds ratio = 5.1] to predict neonatal brain image anomaly. Postlaser septostomy combined with severe Quintero stages could predict PROMs within 3 weeks after laser therapy [p = 0.001, odds ratio = 14.1 and p = 0.03, odds ratio = 5.4, respectively] and delivery before the gestational age of 28 weeks [p = 0.017, odds ratio = 4.5 and p = 0.034, odds ratio = 2.3, respectively]. The risk of pseudoamniotic band syndrome was not increased by postlaser septostomy in this case series. CONCLUSIONS: Postlaser septostomy in TTTS was associated with poorer fetal survival and more adverse perinatal outcomes even after considering severe Quintero stages before laser therapy. Efforts should be made to prevent septostomy during laser therapy, and septostomy as the primary method to treat TTTS is not advisable.

Case series: Amniotic band sequence with craniofacial abnormalities.

BACKGROUND: To objectively describe craniofacial, visual, and neurological features associated with amniotic band syndrome (ABS) and discuss likely associated multifactorial etiology. METHODS: A retrospective review of patients identified with ABS and concomitant limb involvement and craniofacial features was conducted. The following data were collected from the patients' medical records: demographic information, past medical history including birth history, surgical history, previous clinic visits/physical exams, description of craniofacial features and ABS, family history, any noted obstetric complications, visceral features, visual features, craniofacial features, intracranial features, neurological symptoms, developmental features, diagnostic tests (including radiographs, IQ testing, EEG findings, chromosomes), photographs, and treatment history. RESULTS: Seven patients were included in the final cohort, all of whom had a cleft lip with six having both cleft lip and palate. Other craniofacial abnormalities seen were facial clefts which were vertical oblique in nature, tear duct involvement, cranial deformities that required surgical correction with cranial reconstruction, recorded hypertelorism with vision and gaze abnormalities, coloboma, lagopthalmos and optic never dysplasia. CONCLUSIONS: This case series presents seven children with craniofacial involvement associated with amniotic band sequence and attempts to categorize the salient dysmorphology and neurocognitive development. Major craniofacial anomalies in patients with ABS is a rare clinical finding that cannot be completely explained on the basis of premature amniotic layer disruption alone. This study supports that the dysmorphology seen in cases of ABS with craniofacial involvement is complex and most likely multifactorial. LEVEL OF EVIDENCE: IV Case Series.

Síndrome de Banda Amniótica / Amniotic Band Syndrome

Amniotic band sequence or syndrome, is the term applied to a wide range of congenital anomalies, as a group of congenital birth defects caused by entrapment of fetal parts (usually a limb or digits) in fibrous amniotic bands while in utero. Before the baby was born, the body parts shows signs of arm, fingers, etc, that were caught and estrangled. Amniotic band syndrome can cause a number of different birth defects depending on which body part(s) is affected. Amniotic band sequence (ABS) is a rare condition caused by strands of the amniotic sac that separate and entrangle digits, limbs or other parts of the fetus. This constriction can cause a variety of problems depending on where the strands are located and how trightly they are wrapped. ABS can cause a broad spectrum of anomalies ranging from simple band constrictions to major craniofacialand visceral defects. This causes deformations, malformation and disruption, that results in incapacity or death. The aims of the present report, were to present a review of the literature concerning with this pathology, describing the clinical characteristics, etiology, diagnosis and prognosis, in order to improve the efficacy of the prenatal management

Malformations attributed to the process of vascular disruption.

BACKGROUND: Several malformations have been attributed to the process of vascular disruption. The central hypothesis for this etiology is that blood flow to a structure has been altered after that structure had formed normally. The decreased blood flow leads to hypoxia, endothelial cell damage, hemorrhage, tissue loss, and repair. After recovery, some structures are normal and others show either tissue loss or structural abnormalities, such as syndactyly and constriction rings. METHODS: The phenotypic features of the 7,020 infants with one or more malformations, who were born to women who had always planned to deliver at Brigham and Women's Hospital (BWH) between, 1972 and 2012, that is, maternal nontransfers, were reviewed. The phenotypes associated with vascular disruption, such as the amniotic band syndrome and terminal transverse limb defects (TTLD), were identified. RESULTS: One hundred and five fetuses and infants had malformations attributed to the process of vascular disruption. Some specific causes of the amniotic band limb deformity were identified. TTLD with associated small digit-like nubbins occurred at three levels: proximal forearm, wrist, and metacarpal-phalangeal joint. Other causes included severe hemoglobinopathies and exposures to misoprostol and to prenatal procedures. CONCLUSIONS: Malformations attributed to the process of vascular disruption were a distinctive entity, among the recognized etiologies. The timing of the causative event in the first trimester was established for infants with exposures to either the prostaglandin misoprostol or the prenatal diagnosis procedure chorionic villus sampling. One challenge is to identify the developmental steps in vascular disruption when no causative exposure can be identified.

Pseudoamniotic Band Syndrome After Fetoscopic Laser Ablation of Placental Anastomoses for Twin-Twin Transfusion Syndrome: Two Case Reports and Systematic Review.

Pseudoamniotic band syndrome is a rare complication that occurs after invasive procedures for complicated monochorionic twins. We report 2 cases of intrauterine recipient fetal death after laser therapy for twin-twin transfusion syndrome due to umbilical cord constriction by the amniotic band.

Pseudoamniotic Band Syndrome Post Fetal Thoracoamniotic Shunting for Bilateral Hydrothorax.

INTRODUCTION: Pseudoamniotic band syndrome (PABS) occurs iatrogenically after fetal surgery or amniocentesis due to chorioamniotic membrane separation. Separation of the amnion from the chorion can expand to form fibrous amniotic bands that can envelope fetal limbs or the umbilical cord, with consequences ranging from limb constriction to fetal demise. CASE REPORT: We report a case of bilateral fetal pleural effusions at 27 weeks' gestation treated by bilateral thoracoamniotic shunts. Following shunt placement, the hydrothorax resolved. However, chorioamniotic membrane separation developed resulting in PABS with subsequent umbilical cord strangulation and fetal demise at 32 weeks' gestation. CONCLUSION: PABS has been previously described in the literature following various fetal interventions. This is the first reported case of pseudoamniotic band syndrome after placement of fetal thoracoamniotic shunts. A high index of suspicion is required to diagnose PABS via postoperative ultrasound. Post intervention chorioamniotic membrane separation warrants close surveillance for sonographic evidence of PABS.

Uterine contractility as a cause of amniotic band syndrome.

OBJECTIVE: The objective of this study was to determine whether puncturing the uterine wall and the amnion causes uterine contractions that result in fetal abnormalities. MATERIALS AND METHODS: An experimental study was performed using four groups of three female rabbits. Group A received a puncture of the amniotic membranes of one of the uteri on day 15 of gestation followed by group B on day 16, group C on day 17, and group D on day 18. The duration and force of contractions and fetal abnormalities were determined. RESULTS: There were immediate contractions after the puncture, which lasted 20 to 132 seconds with forces that ranged from 309 to 4,411 mg. All of the experimental fetuses exhibited anomalies of the head and extremities, exencephaly, cleft palates, and an absence of eye-lids. CONCLUSION: Injury to the uterine wall and the aniion can immediately cause uterine contractions, which are associated with different types of fetal abnormalities.

Pseudoamniotic Band Syndrome after In Utero Intervention for Twin-to-Twin Transfusion Syndrome: Case Reports and Literature Review.

Pseudoamniotic band syndrome (PABS) is a rare iatrogenic complication that arises after invasive procedures in monochorionic twins. We report 3 cases of PABS, 2 after fetoscopic laser photocoagulation and 1 after bipolar cord coagulation. Two cases were detected antenatally by ultrasound; out of the two, one underwent successful fetoscopic release of amniotic band, which is the first report in twin pregnancy to our knowledge. In our centre, the incidence of PABS was found to be 2%. There were 25 cases of PABS reported previously, of which 12 cases with clinical details were reviewed together with our 3 cases. The fetal limbs were involved in all 15 cases, leading to constriction or amputation. The umbilical cord was involved in 2 cases, resulting in fetal death in one and pregnancy termination in the other. Antenatal detection of PABS is rare (27%; 4/15) as this requires a high index of suspicion. Serial postoperative targeted ultrasound surveillance of the fetal limbs and umbilical cord is necessary, particularly when features of septostomy or chorioamniotic membrane separation are found. Colour Doppler examination for the perfusion of the affected limb should be performed when PABS is detected. Fetoscopic release of amniotic band could salvage the fetal limb from amputation when impaired blood flow is detected.

Limb constriction secondary to pseudoamniotic band syndrome after selective fetoscopic laser surgery: report of a case with a favorable outcome.

Pseudoamniotic band syndrome (PABS) is an iatrogenic complication that causes entanglement of fetal parts in a constrictive sheet of detached or ruptured amniotic membrane after an invasive procedure, namely amniocentesis, amnioreduction or septostomy in twins. The incidence and risk factors for PABS after fetoscopy-guided laser have not been documented [Winer et al.: Am J Obstet Gynecol 2008;198:393.e1-393.e5]. We report a case of monochorionic biamniotic twin pregnancy submitted to selective fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome at 16 weeks of gestation. The procedure was complicated by the death of one of the fetuses at 24 weeks of gestation. Moreover, the surviving twin was diagnosed postnatally with pseudoamniotic band syndrome, presenting with affected limbs. The newborn was submitted to surgical correction of these lesions with a successful outcome and was discharged on day 15.

Development of a fetal rabbit model to study amniotic band syndrome.

Amniotic band syndrome (ABS) is a group of fetal malformations caused by fibrous adherences. Species such as sheep, rats, and mice have been used to study this syndrome. We developed a fetal rabbit model using 24 fetuses from punctured uteri. We found one case of syndactyly, one case of amniotic banding, two cases of extremity deformities, one case of a tail deformity, one case of head compression, and one case of open eyelids. Other malformations have been described in an amnion rupture sequence model (exencephaly and cleft palate). The rabbit fetus is an adequate model in which to develop this syndrome.

Incidence and clinical implications of early inadvertent septostomy after laser therapy for twin-twin transfusion syndrome.

OBJECTIVE: To evaluate the incidence and clinical outcome of inadvertent septostomy after fetoscopic laser therapy for twin-twin transfusion syndrome (TTTS) and, particularly, to explore its association with the risk of developing pseudoamniotic band syndrome (PABS). METHODS: In a cohort of 414 consecutive monochorionic twin pregnancies with confirmed TTTS treated with laser, the incidence of postoperative septostomy within 1 week of the procedure was recorded prospectively. Rates of preterm delivery, preterm premature rupture of membranes (PPROM), intrauterine fetal demise (IUFD) and PABS were compared among cases with and without septostomy. RESULTS: The mean gestational age at laser therapy was 20.4 (range, 15.3-27.6) weeks. Postoperative septostomy occurred in 30 (7.2%) cases. Pregnancies complicated with septostomy had a significantly higher proportion of preterm delivery before 32 weeks (76.7% vs. 30.2%, P < 0.001), PPROM before 32 weeks (46.7% vs. 19.0%, P < 0.001), IUFD (43.3% vs. 25.8%, P < 0.05) and PABS (13.3% vs. 1.0%, P < 0.001), compared with pregnancies without septostomy. CONCLUSIONS: Inadvertent septostomy occurred in 7% of cases after fetoscopic laser therapy and was associated with a substantially increased risk of adverse perinatal outcome and PABS.

Chorionic villus sampling and hemangiomas.

Chorionic villus sampling (CVS) is a widely used and safe method of prenatal diagnosis. In the 1990s, concerns were raised at several medical centers that there was an increased risk to the exposed fetus for the occurrence of limb deficiencies, hemangiomas, and other vascular disruption defects. The risk was greater when the procedure was performed earlier in pregnancy, such as 8 or 9 weeks of gestation. The postulated mechanisms for the fetal injury included blood loss, hypoperfusion, hypoxia, endothelial cell damage, hemorrhage, and tissue loss. The effect was most common in tissues with end arteries, such as digits, tongue, brain stem, and intestine. The associated hemangiomas were infantile hemangiomas. They were more common on the head, neck, and thorax and more often multiple in infants exposed to CVS. One postulated mechanism for the occurrence of these hemangiomas is embolization of angioblasts or endothelial cells from the placenta to the fetal skin. A question to be answered is whether the infantile hemangiomas in children exposed to CVS differ in immunohistologic characteristics from similar hemangiomas in children not exposed to CVS during pregnancy.

Maternal vasoactive exposures, amniotic bands, and terminal transverse limb defects.

BACKGROUND: Limb reduction deficiencies that are accompanied by amniotic bands (AB-Ls) and terminal transverse limb deficiencies (TLDs) have each been attributed to vascular disruption; for the former, however, it is not clear if amniotic bands are the primary cause of or are secondary to vascular disruption. If amniotic bands are secondary to vascular disruption, then a shared pathogenesis for each case group might be exhibited by similar risk factors. METHODS: We evaluated maternal age, education, race/ethnicity, parity, pregnancy wantedness, and vasoactive exposures among 139 AB-L and 373 TLD cases, using interview data collected from mothers in 10 states by the National Birth Defects Prevention Study. Vasoactive exposures included maternal cigarette smoking and use of decongestants, nonsteroid anti-inflammatory drugs, and antihypertensive drugs in the periconceptional period. RESULTS: Increased risk estimates were observed for Black mothers (OR 2.5; 95% CI: 1.5-4.1) and nulliparous mothers (2.1; 1.4-3.0) in relation to AB-L, while neither was associated with TLD. Hispanic women (1.4; 1.0-1.9) and those not wanting the pregnancy (1.5; 1.1-2.1) had increased risks of TLD, but not AB-L. Maternal cigarette smoking and aspirin use each increased the risk of AB-L, but not TLD; while decongestants and possibly antihypertensive medications increased the risk of TLD, but not AB-L. CONCLUSIONS: The lack of consistent findings for the two case groups suggests that AB-L and TLD may be distinct entities. The inconsistencies also suggest that these vasoactive exposures may not be markers for vascular disruption or that vascular disruption may not play a major role in the pathogenesis of these two types of limb deficiencies.