Therapy For Twin-twin Transfusion Syndrome Research Articles

Neurodevelopmental outcome at 6 years of age after intrauterine laser therapy for twin‐twin transfusion syndrome

This study was undertaken to evaluate neurodevelopmental outcome of children at 6 years of age after intrauterine laser therapy for Twin-twin transfusion syndrome (TTTS). This is part of a longitudinal study in children after intrauterine laser therapy for TTTS; 190 of 254 (74.8%) children, previously investigated at a median age of 2 years 10 months, were re-evaluated at 6 years 5 months (range 4 years 11 months -10 years 4 months). Sixty-four patients were not examined due to loss of contact. The median gestational age at birth was 34 + 3 weeks. The study included a physical/neurological examination, a standardized neurodevelopmental test (Kaufman-ABC) and/or results from the national screening programme for children as well as questionnaires. Patients were grouped in three outcome categories: group I: normal examination and test result; group II: minor neurological deficiencies and normal test results; group III: major neurological deficiencies and/or test results below minus two standard deviations. The following results were obtained at 6 years 5 months (for comparison, results of the same patients at 2 years 10 months in brackets). Group I: 79.5% (84.2%); group II: 11.6% (8.9%); group III: 8.9% (6.8%). Twenty-one (11%) patients had a worse and 8 (4.2%) an improved classification at 6 years 5 months as compared to 2 years 10 months. Overall, the results with 6 years did not significantly differ from the results with 2 years. Neurodevelopmental outcome at 6 years 5 months was not statistically, significantly different from outcome at 2 years 10 months.

Neurodevelopmental Outcomes After Laser Therapy for Twin–Twin Transfusion Syndrome

To perform a systematic review of the literature regarding the occurrence of neurologic morbidity, neurologic impairment, or neurologic morbidity and impairment of patients treated with laser therapy for twin-twin transfusion syndrome. The PubMed, MEDLINE, EMBASE databases and reference lists were searched up to December 2010 for studies describing outcomes in laser-treated twin-twin transfusion syndrome pregnancies. METHODS FOR STUDY SELECTION: Inclusion criteria were twin-twin transfusion syndrome diagnosed with standard criteria and treated by laser therapy and neurologic morbidity and neurologic impairment collected at birth or 28 days after birth. Exclusion criteria were omission of at least one criterion; data in graphs or percentage; and non-English publications, letters, personal communications. Data recorded were rates and length of successful follow-up, age at diagnosis and type of neurologic morbidity, affected donors and recipients, prevalence of neurologic morbidity, and neurologic impairment for twin sets. From 15 articles, the incidence of neurologic morbidity at birth was 55 out of 895 (6.1%), without differences between donors and recipients (19/249, 7.6% compared with 16/273, 5.8%; odds ratio [OR] 1.36; 95% confidence interval [CI] 0.68-2.70). At follow-up, the incidence of neurologic impairment was 140 out of 1,255 (11.1%), with cerebral palsy the most frequent (60/151, 39.7%). Neurologic impairment was identified equally between donors and recipients (48/330, 14.5% compared with 54/364, 14.8%; OR 1.02; 95% CI 0.66-1.57), and between one survivor and two survivors for twin sets (24/139, 17.3% compared with 88/489, 18.0%; OR 0.67; 95% CI 0.18-2.49). A small number (11.1%) of cases of twin-twin transfusion syndrome treated with laser therapy are affected with neurologic impairment that manifests during infancy. A strict follow-up of apparently healthy neonates is warranted.

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

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). 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. 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. 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.

OP18.09: Cardiovascular changes in the donor twin after laser photocoagulation therapy for twin-twin transfusion syndrome (TTTS)

OP18.09: Cardiovascular changes in the donor twin after laser photocoagulation therapy for twin-twin transfusion syndrome (TTTS)

OP22.07: Lung function at school age of 60 children after intrauterine laser therapy for twin-twin transfusion syndrome (TTTS)

OP22.07: Lung function at school age of 60 children after intrauterine laser therapy for twin-twin transfusion syndrome (TTTS)

OC02.03: Neurodevelopmental outcome at six years of age after intrauterine laser therapy for twin-twin transfusion syndrome (TTTS)

Objective: To compare an animal model of growth restriction by selective ligature of uteroplacental vessels with a model of severe hyponutrition. Methods: 16 New Zealand pregnant rabbits were included in the placental insufficiency (PI) model, in which a 40–50% of uteroplacental vessels were ligated at 25d of gestation. Contralateral horn were considered as control. After surgery, dams were allowed free access to water and standard chow. 2 New Zealand pregnant rabbits were included in the hyponutrition (HN) model, in which a sham-surgery was performed at 25d. After surgery, hyponutrition was induced by restricting up to 70% of the normal diet. Pulsed Doppler assessment was performed before Cesarean delivery. Results: Mortality rate showed significant differences between experimental groups (14,3% control; 5.0% HN; and 54.2% PI (p<0.001)). Among survivors, all biometric parameters showed a consistent and significant gradient across the experimental groups. Doppler assessment demonstrated a significant linear increase of ductus venosus and a linear decrease of umbilical vein blood flow across study groups. Additionally, umbilical artery and aortic isthmus showed a non-significant trend to increase through experimental groups. Conclusion: Selective ligature of uteroplacental vessels results in an animal model of fetal growth restriction with biometric and hemodynamic changes that closely resembles the clinical condition. This surgical model could be useful to investigate effects of hypoxic condition on different key organs, such as brain and heart.

OP18.08: Prediction of fetal outcome following laser therapy for twin-twin transfusion syndrome by pre and post-operative Doppler changes of umbilical artery

OP18.08: Prediction of fetal outcome following laser therapy for twin-twin transfusion syndrome by pre and post-operative Doppler changes of umbilical artery

642: Does velamentous cord insertion affect outcomes after laser therapy for twin-twin transfusion syndrome?

642: Does velamentous cord insertion affect outcomes after laser therapy for twin-twin transfusion syndrome?

In utero fetal oximetry via visible light spectroscopy in twin-twin transfusion syndrome

The purpose of this study was to assess fetal tissue venous oxygenation (StO2%) in utero during laser therapy for twin-twin transfusion syndrome via visible light spectroscopy (VLS). StO2% was measured in 10 donor and recipient twins at the level of the skin and placenta before and after laser therapy (SLPCV). Pre-SLPCV skin StO2% was significantly lower in the donor than in the recipient twin (21.6 +/- 6.2 vs 31.2 +/- 8.6, respectively; P = .01), but the difference disappeared after SLPCV. Placental surface StO2% measurements in 5 patients showed a significant increase in StO2% in the territory of the recipient (P = .04). Preoperative linear streaming as evidence of nonadmixing deoxygenated and oxygenated blood disappeared after SLPCV. In utero StO2% measurement is possible with VLS. Donor twins can have significantly less StO2% than recipient twins, but this is corrected after SLPCV. Further studies are warranted to determine the value of in utero VLS oximetry.

Fetal growth after laser therapy for twin-twin transfusion syndrome

The objective of the study was to compare twin weight discordance and prevalence of intrauterine growth restriction (IUGR) before laser therapy and after birth in pregnancies complicated by twin-twin transfusion syndrome (TTTS). Women with TTTS who underwent laser therapy with dual neonatal survivors born at least 28 days after surgery were studied. Estimated fetal weight (EFW) discordance at the preoperative sonogram and birthweight (BW) discordance were calculated. Weights below gestational age-corrected 10th percentile at sonogram and at birth for each twin were designated as IUGR. Among 211 women studied, the mean EFW discordance measured 26.6% and mean BW discordance was 18.4%, yielding a mean 8.2% decrease in weight discordance (P < .001). Comparing IUGR diagnoses before surgery and at birth, the recipient's proportion was unchanged (9.5% vs 7.1%, P = .353), whereas the donor's proportion decreased (64.5% vs 28.9%, P < .001). Twin weight discordance and donor fetus IUGR appear to improve after laser therapy for TTTS.

516: Perinatal survival after third-generation laser therapy for twin-twin transfusion syndrome

There have been conflicting reports regarding perinatal outcome after selective laser photocoagulation of communicating vessels (SLPCV) for the treatment of twin-twin transfusion syndrome (TTTS). The aim of this study was to assess perinatal outcome in TTTS cases treated by third-generation SLPCV.

OP10.11: Polish experience with fetoscopic laser surgery for TTTS

Objectives: To study the impact of treatment with endoscopic laser ablation for twin–twin transfusion syndrome (TTTS) on the CHOP cardiovascular score. Methods: Retrospective review of patients undergoing laser ablation for TTTS with both preoperative and postoperative fetal echocardiograms. Results: Between June 2005 and February 2007, 41 patients underwent laser ablation therapy for TTTS. Quintero staging was Stage 2 for 19, Stage 3 for 19 and Stage 4 for three. The preoperative CHOP scoring was Grade I (0–5) = 22; Grade II (6–10) = 7; Grade III (11–15) = 8; Grade IV (16–20) = 4. The mean gestational age at treatment was 20.6 ± 2.07 weeks. Fifteen patients underwent both preoperative and postoperative fetal echocardiography with an average of 3 days between the preoperative evaluation and treatment and an average of 10 days between treatment and post-op evaluation. The mean preoperative CHOP score was 9.9 ± 1.4 and the mean postoperative CHOP score was 4.8 ± 0.9 (P = 0.0002). Conclusions: The CHOP cardiovascular score measures physiologic perturbations that underlie the clinical findings in TTTS. Following treatment with laser ablation, clinical resolution is associated with a significant decrease in the CHOP cardiovascular score. This provides further validation of the CHOP cardiovascular score as a tool for the evaluation of pregnancies complicated by TTTS.

Paradoxical scalloped placenta with polyhydramnios in twin–twin transfusion syndrome

Objective. To describe the paradoxical occurrence of a scalloped placenta in the presence of polyhydramnios and assess its clinical significance in pregnancies complicated by twin–twin transfusion syndrome (TTTS) treated with laser therapy.Methods. All patients who underwent laser therapy for TTTS between January 2003 and April 2004 were studied. TTTS was diagnosed and staged using the Quintero staging system. Normally the placenta is characterized by undulations of the fetal-placental surface visible by ultrasound (scalloped placenta). Patients with polyhydramnios will typically have a flattened, smooth, non-scalloped placenta. Operative tapes were reviewed and placental type assigned. Pre-, intra-, and postoperative characteristics of each study patient were obtained.Results. Fifteen of 120 patients (12.5%) were noted to have a scalloped placenta despite having polyhydramnios. There was no difference in mean gestational age at laser treatment (20.3 ± 0.5 vs. 19.6 ± 0.6 weeks, p = 0.66) or in stage (p = 0.07) between the two groups. The median and range preoperative maximum vertical pocket (MVP) in the recipient gestational sac differed significantly between the scalloped and non-scalloped patients (8.3 (8–12) vs. 10.5 (8–17), p = 0.001). All 15 patients (100%) with a scalloped placenta required an amnioinfusion to expose all vascular anastomoses, while amnioinfusion was necessary in only 28 of the 105 patients (26.7%, p < 0.001) with a non-scalloped placenta. Postoperative patent placental vessel was identified by surgical pathology in 6.7% of the scalloped placenta group vs. 1.9% of the non-scalloped placenta group (p = NS).Conclusion. The definition of TTTS requires an MVP ≥8 cm in the recipient sac. Most patients will have a flattened placenta as a result of polyhydramnios in this sac. Our data show that a paradoxical scalloped placenta may still be present in approximately 12.5% of patients. This preoperative sonographic finding alerts to the potential need for amnioinfusion during laser therapy for TTTS to disclose all vessels to avoid missing placental vascular anastomoses. Amniocenteses should be avoided if possible in patients considering laser therapy to minimize the likelihood of iatrogenic placental scalloping.

Multimodality and sequential therapy for twin-twin transfusion syndrome (TTTS): A stage and gestational age based approach to the use of amnioreduction (AR), selective fetoscopic laser photocoagulation (SFLP), and radio frequency ablation (RFA)

Multimodality and sequential therapy for twin-twin transfusion syndrome (TTTS): A stage and gestational age based approach to the use of amnioreduction (AR), selective fetoscopic laser photocoagulation (SFLP), and radio frequency ablation (RFA)

How much fluid should be removed after laser therapy for twin-twin transfusion syndrome?

How much fluid should be removed after laser therapy for twin-twin transfusion syndrome?

Effect of a prior amniocentesis in patients undergoing laser therapy for twin-twin transfusion syndrome

FOR TWIN-TWIN TRANSFUSION SYNDROME RAMEN CHMAIT, CRISTINA ROSSI, RUBEN QUINTERO, Florida Institute for Fetal Diagnosis and Therapy, Tampa, Florida OBJECTIVE: To assess the implications of a previous therapeutic amniocentesis (PTA) in patients that subsequently underwent laser therapy for twin-twin transfusion syndrome (TTTS). STUDY DESIGN: All twin pregnancies that underwent laser therapy for TTTS from January 1999 through December 2003 were studied. Patients with no PTA (PTA-) were compared to those with one or more PTA’s (PTA+) in regards to demographics, operative complications, and outcome measures including gestational age at delivery and survival of at least one neonate. Statistical significance was determined if P ! .05. RESULTS: Three hundred and forty patients underwent laser therapy for TTTS during the study period. Of these, 203 (60%) were PTAand 137 (40%) were PTA+. The median number of amniocenteses in the PTA+ group was 1 (range 1-6), with a median total volume withdrawn of 1550cc (range 100-12000). Severity of the disease was similar between the two groups in terms of Quintero stages I/II and stages III/IV. On average, the PTAgroup underwent surgery one week earlier than the PTA+ group (20.1 vs. 21.2 weeks’ gestation, P = .0001). Placental location was anterior more often in the PTA(49%) than in the PTA+ (36%, P = .019) group, yet amnioexchange to correct blood discolored amniotic fluid was necessary less often in the PTA(9%) than in PTA+ (20%, P = .009) group. Gestational age at delivery was greater in the PTAthan in the PTA+ patients (32.0 vs. 30.6 weeks, P = .008), with a trend towards improved survival (89% vs. 81%, P = .0543). CONCLUSION: Therapeutic amniocentesis prior to laser therapy is associated with increased operative risk, earlier gestational age at delivery, and a trend towards lower perinatal survival. Patients with TTTS who desire laser therapy should avoid undergoing prior therapeutic amniocenteses.

Maternal blood pressure and heart rate changes relative to the anesthesia technique during laser therapy for twin-twin transfusion syndrome

Maternal blood pressure and heart rate changes relative to the anesthesia technique during laser therapy for twin-twin transfusion syndrome

The role of Doppler studies in predicting individual intrauterine fetal demise after laser therapy for twin-twin transfusion syndrome.

To investigate the role of Doppler studies in predicting individual fetal demise in patients scheduled for selective laser photocoagulation of communicating vessels (SLPCV) for twin-twin transfusion syndrome (TTTS). Doppler studies of the umbilical artery, umbilical vein, ductus venosus, tricuspid valve regurgitation and middle cerebral artery were performed in the donor and recipient twins before and 24 hours after SLPCV. Results were analyzed cross-sectionally and longitudinally. As multiple comparisons were made, an a priori alpha rejection was set at P < 0.001. One hundred and ten consecutive patients were available for analysis. Overall fetal survival was 68.6% (151/220) with at least one survivor in 88.2% (97/110) of cases. Absent or reversed end-diastolic velocity in the umbilical artery of the donor twin was the only preoperative Doppler result predictive of intrauterine fetal demise (IUFD) (10/15, 66.7%, P < 0.001). Postoperatively, reversed flow during atrial contraction in the ductus venosus of the donor twin showed a trend towards prediction of IUFD of this fetus (4/5, 80%, P = 0.007). No other Doppler studies, including the longitudinal analyses, were predictive of IUFD. Our data suggest that preoperative absent or reversed end-diastolic velocity in the umbilical artery may be useful in predicting individual fetal demise of the donor twin in TTTS patients scheduled for SLPCV. This may reflect the role of decreased individual placental mass that may be associated with some donor twins. The inability of other Doppler studies to predict individual IUFD may be explained preoperatively by the effect of the interfetal vascular connections on the individual Doppler signals and postoperatively by the effect of surgery or the timing of the assessment. Our findings may be important in patient counseling, in furthering understanding of the disease, and perhaps in improving surgical technique.

P253: Middle cerebral artery Doppler assessment of fetal anemia in the surviving co-twin after laser therapy for twin-twin transfusion syndrome

P253: Middle cerebral artery Doppler assessment of fetal anemia in the surviving co-twin after laser therapy for twin-twin transfusion syndrome

Fetal urine and amniotic fluid in monochorionic twins with twin-twin transfusion syndrome: Simulations of therapy

Objective: Therapy for twin-twin transfusion syndrome includes amnioreduction, septostomy, and laser ablation, but there is no accepted standard of care. Mechanisms for the reported improvement in survival are incompletely understood. We sought to model the mechanisms and predict the response of varying severities of twin-twin transfusion syndrome and placental angioarchitectures to current therapies to determine optimal clinical interventions. Study Design: We used our mathematic model of twin-twin transfusion syndrome that predicts fetal and amniotic fluid abnormalities that are related to the placental angioarchitecture. Amnioreduction was modeled as reduction in amniotic fluid volume; septostomy was modeled as the merging of donor and recipient amniotic fluid, and laser ablation was modeled as the cessation of all placental anastomotic blood flows. Results: Amnioreduction reduces amniotic fluid pressure, which improves transplacental fluid flow from mother to fetus and increases both donor and recipient blood volume. However, net arteriovenous transfusion increases, because of increased donor arterial pressure, which negates, in part, the benefit of amnioreduction. Septostomy allows amniotic fluid to be swallowed by the donor, with minimal effects on donor growth and blood volume. Laser ablation eliminates anastomotic exchange of blood and reduces discordant fetal growth. Conclusion: Amnioreduction may be effective in milder twin-twin transfusion syndrome pregnancies but ineffective in severe cases. Septostomy is unlikely to offer significant therapeutic efficacy. Laser ablation is equally effective in mild and severe twin-twin transfusion syndrome but has a higher spontaneous abortion rate than amnioreduction. The model indicates improved outcomes with the use of amnioreduction in mild twin-twin transfusion syndrome cases and with laser ablation in severe cases. (Am J Obstet Gynecol 2001;185:996-1003.)