Treatment Of Twin-to-twin Transfusion Syndrome Research Articles

The Effect of Treatment of Twin-Twin Transfusion Syndrome on the Diagnosis-to-Delivery Interval

AbstractNo randomised controlled trials of treatment of twin-to-twin transfusion syndrome (TTTS) exist. Since severely preterm neonatal survival has increased over time, survival as an outcome measure is confounded by improvements in neonatal care. The diagnosis-to-delivery interval is a measure of success of treatment independent of improvements in neonatal care. We wished to evaluate whether treatment of TTTS is associated with a lengthening of the diagnosis-to-delivery interval. MEDLINE search was performed supplemented by careful reference review. All TTTS series were included where the following information on each patient was available: survival, fetal demise, gestational age at diagnosis and diagnosis-to-delivery interval in days. Inclusion criteria: gestational age at diagnosis < 29 weeks and diagnosis by ultrasound in the absence of maternal symptoms. Cases undergoing multiple types of treatment were excluded. Eight publications met inclusion criteria and included the following cases: controls (n = 16), amnioreduction (n = 61), septostomy (n = 12), and fetoscopic laser occlusion of chorioangiopagus vessels (n = 51). There was no difference in the diagnosis-to-delivery interval, overall survival, at least one survivor, or number of fetal deaths between the four groups. Logistic regression using at least one survivor as the dependent variable revealed a positive association with gestational age at diagnosis and with diagno-sis-to-delivery interval, a negative correlation with fetal death, and no correlation with treatment group. We conclude that there is no difference in diagnosis-to-delivery interval or survival for any treatment for TTTS compared to expectant management. The lack of significance appears to be due to small sample sizes.

Selective Versus Non-Selective Laser Photocoagulation of Placental Vessels in Twin-to-Twin Transfusion Syndrome

Objective We have recently described a surgical technique for the treatment of twin-to-twin transfusion syndrome (TTTS) that allows precise identification of vascular anastomoses (selective laser photocoagulation of communicating vessels, or S-LPCV). The purpose of this study was to compare S-LPCV with the previous non-selective technique (NS-LPCV) that targeted all vessels crossing the dividing membrane. Materials and Methods Patients with TTTS were treated with NS-LPCV from May 1994 to June 1997 and with S-LPCV from July 1997 to December 1999. TTTS was defined as polyhydramnios of ≥8 cm maximum vertical pocket (MVP) in the recipient twin and oligohydramnios of ≤2 cm MVP in the donor twin. Outcome was measured as survival per number of pregnancies and per number of fetuses together with limited morbidity data. Results NS-LPCV was used in 18 patients and 74 were treated with S-LPCV. Three patients interrupted their pregnancies electively after surgery (S-LPCV) and were removed from further analysis. Survival of at least one fetus was higher in S-LPCV (83.1%) than in NS-LPCV (61.1%) (P = 0.04), mostly due to a lower rate of dual intra-uterine fetal demise in S-LPCV (5.6%) than in NS-LPCV (22%) (P = 0.05). There were more hydropic fetuses in the NS-LPCV group (27%) than in the S-LPCV group (5.4%), but this difference did not account for the results. There was no difference in the survival per number of fetuses between the two groups. Conclusions S-LPCV represents an important evolution in the surgical treatment of TTTS. The use of this technique by all centers should allow better comparison of fetal survival and morbidity rates. S-LPCV should be the standard technique in trials comparing amniocentesis versus laser for the treatment of severe TTTS. Copyright © 2000 International Society of Ultrasound in Obstetrics and Gynecology

The Role of Ultrasound in Multiple Pregnancy

AbstractThe advances in reproductive technologies have changed the demographics of multifetal pregnancies. In the first trimester, ultrasound allows to diagnose the number of multiples, chorionicity and amnionicity, the presence or absence of nuchal translucency, early growth discordance, severe malformations and the origin of activities and contacts between multiples. In the second and third trimester, the opportunity to examine the cervix by transvaginal ultrasound should not be missed to detect the risk of premature delivery. Ultrasound is essential for the early grading and treatment of twin-to-twin transfusion syndrome (TTTS), the diagnosis of malformations and growth disturbances. Doppler velocimetry has proven to be able to reduce perinatal mortality in twin pregnancies. Finally, ultrasound is used for the detection of the position of multiples and the decision of the optimal route of delivery. This is of main importance in delayed interval delivery and expectant management of multifetal pregnancies and early cervical dilatation.

The role of ultrasound in multiple pregnancy.

The advances in reproductive technologies have changed the demographics of multifetal pregnancies. In the first trimester, ultrasound allows to diagnose the number of multiples, chorionicity and amnionicity, the presence or absence of nuchal translucency, early growth discordance, severe malformations and the origin of activities and contacts between multiples. In the second and third trimester, the opportunity to examine the cervix by transvaginal ultrasound should not be missed to detect the risk of premature delivery. Ultrasound is essential for the early grading and treatment of twin-to-twin transfusion syndrome (TTTS), the diagnosis of malformations and growth disturbances. Doppler velocimetry has proven to be able to reduce perinatal mortality in twin pregnancies. Finally, ultrasound is used for the detection of the position of multiples and the decision of the optimal route of delivery. This is of main importance in delayed interval delivery and expectant management of multifetal pregnancies and early cervical dilatation.

WS13: Multiple pregnancy WS13‐01The effect of treatment of twin‐to‐twin transfusion syndrome on the diagnosis to delivery interval

PurposeNo randomized controlled trials of treatment of twin‐to‐twin transfusion syndrome (TTTS) exist. Since severely preterm neonatal survival has increased over time, survival as an outcome measure is confounded by calendar time. The diagnosis‐to‐delivery interval is a calendar year independent measure of success of treatment. We wished to evaluate whether treatment of TTTS is associated with a lengthening of the diagnosis‐to‐delivery interval.MethodsMEDLINE search supplemented by careful reference review. All TTTS series were included where the following information on each patient was available: survival, fetal demise, gestational age (GA) at diagnosis and diagnosis to delivery interval in days.Inclusion criteriaGA ≤ 29 weeks and diagnosis by ultrasound in the absence of maternal symptoms. Cases undergoing multiple types of treatment were excluded. Data were evaluated by Kruskal–Wallis anova, logistic regression & Wilcoxon rank sum testing.ResultsThe 8 publications used included the following cases: controls (n = 16), amnioreduction (n = 61), septostomy (n = 12), and fetoscopic laser occlusion of chorioangiopagus vessels (FLOC) (n = 51). FLOC therapy showed a significantly longer diagnosis‐to‐delivery interval compared to amnioreduction (median 75 vs. 56 days) (p = 0.01). There was no difference in overall survival, at least one survivor, or number of fetal deaths between the 4 groups. Logistic regression using at least one survivor as the dependent variable revealed a positive association with GA at diagnosis and with diagnosis to delivery interval, a negative correlation with fetal death, and no correlation with treatment group.ConclusionsFLOC therapy for TTTS is associated with a longer diagnosis‐to‐delivery interval compared to amnioreduction without a significant increase in survival. The lack of increase in survival appears to be due to a small sample size.

P37Ileal atresia and thrombo‐embolic liver calcifications, a possible complication after treatment with intrauterine laser coagulation therapy for twin to twin transfusion syndrome

BackgroundTwo fetuses with complications after laser coagulation therapy for twin to twin transfusion syndrome (TTTS) are described.Case 1In this patient laser coagulation of the connecting placental vessels was performed at 21 weeks of gestation. Two weeks after this treatment the donor twin had died. Sonography of the survivor showed progressive intestinal distension from 24 weeks onwards. After birth a laparotomy was performed and an ileal atresia was found.Case 2In this patient laser coagulation was performed at 19 weeks of gestation. Premature rupture of membranes occurred at 21 weeks and both fetuses died. At autopsy thrombo‐embolic calcifications were found in the liver of the smallest, donor twin.DiscussionWhereas duodenum atresia is considered a ‘true’ congenital anomaly, jejuno/ileal atresia is thought to be caused by a mesenteric vascular accident during fetal life, which leads to necrosis. Intra‐uterine laser coagulation therapy seems promising in the treatment of TTTS. Although it cannot be proven, this therapy must be regarded as one of the possible causes for the thrombo‐embolic processes described in the two cases.