Barbara Soong

Neurodevelopmental outcome and risk factors for disability for twin-twin transfusion syndrome treated with laser surgery

OBJECTIVE This study was performed to report the neurodevelopmental outcome of survivors of twin-twin transfusion syndrome (TTTS) treated with laser surgery and to determine the risk factors for neurodevelopmental disability. STUDY DESIGN A prospective study of TTTS cases treated with laser was performed. Survivors were assessed at 2 years corrected for prematurity. Neurodevelopmental disability was defined as the presence of cerebral palsy, deafness, blindness, or cognitive impairment with a developmental score >2 SDs below the mean. RESULTS A total of 75 TTTS pregnancies were treated with a perinatal survival rate of 79.3%. A total of 113 survivors were assessed. The rate of cerebral palsy was 4.4% and cognitive impairment was 8%, with a neurodevelopmental disability rate of 12.4%. Quintero stage was the only independent risk factor for neurodevelopmental disability. CONCLUSION The incidence of neurodevelopmental disability in TTTS survivors treated with laser is considerable, with Quintero stage being an independent risk factor.

Selective fetoscopic laser ablation in 100 consecutive pregnancies with severe twin–twin transfusion syndrome

Aims: To report the perinatal outcomes of a large series of twin pregnancies with severe twin–twin transfusion syndrome (TTTS) managed with laser ablation surgery in an Australian tertiary perinatal centre and to compare the outcome with other large cohorts.

Realtime fetal ultrasound by telemedicine in Queensland. A successful venture

We have established a realtime fetal tele-ultrasound consultation service in Queensland, which has been integrated into our routine clinical practice. The service, which uses ISDN transmission at 384 kbit/s, allows patients in Townsville to be examined by subspecialists in Brisbane, 1500 km away. For the 90 tele-ultrasound consultations performed for the first 71 patients, 90% of the babies have been delivered, and outcome data have been received on all the pregnancies. All significant anomalies and diagnoses have been confirmed. The referring clinicians would have physically referred 24 of the 71 patients to Brisbane in the absence of telemedicine. A crude cost–benefit calculation suggests that the tele-ultrasound service resulted in a net saving of A

Perinatal outcomes with laser surgery for twin-twin transfusion syndrome.

6340, and at the same time enabled almost four times the number of consultations to be carried out.

OC30.10: Learning curve for fetoscopic laser surgery for severe twin–twin transfusion syndrome can be shortened

The aim of this tertiary hospital-based cohort study was to determine and compare perinatal outcome and neonatal morbidities of pregnancies with twin-twin transfusion syndrome (TTTS) before and after the introduction of a treatment program with laser ablation of placental communicating vessels. Twenty-seven pregnancies with Stage II-IV TTTS treated with amnioreduction were identified (amnioreduction group). The data were compared with that obtained from the first 31 pregnancies with Stage II-IV TTTS managed with laser ablation of placental communicating vessels (laser group). Comparisons were made for perinatal survival and neonatal morbidities including abnormalities on brain imaging. The median gestation at therapy was similar between the two groups (20 vs. 21 weeks, p = .24), while the median gestation at delivery was significantly greater in the laser treated group (34 vs. 28 weeks, p = .002). The perinatal survival rate was higher in the laser group (77.4% vs. 59.3%, p = .03). Neonatal morbidities including acute respiratory distress, chronic lung disease, requirement for ventilatory assistance, patent ductus arteriosus, hypotension, and oliguric renal failure had a lower incidence in the laser group. On brain imaging, ischemic brain injury was seen in 12% of the amnioreduction group and none of the laser group of infants (p = .01). In conclusion, these findings indicate that perinatal outcomes are improved with less neonatal morbidity for monochorionic pregnancies with severe TTTS treated by laser ablation of communicating placental vessels when compared to treatment by amnioreduction.

P09.30: Perinatal outcomes with laser therapy for severe twin–twin transfusion syndrome

Background: Critical pulmonary stenosis or atresia (PAIVS) diagnosed in the second trimester progresses resulting in right ventricular (RV) growth failure. Fetal pulmonary valvuloplasty may improve outcome. We explore the determinants of right-sided growth in the fetus with PAIVS. Methods: Serial fetal echocardiography in 10 of 14 consecutive fetuses diagnosed with PAIVS in a fetal medicine centre (1999–2003). Assessment of morphology, right and left sided valvular and ventricular growth, Doppler across valves and in arterial and venous ducts (DV). DV waveforms were classified as ‘‘abnormal’’ if absent or reversed end diastolic flow (AREDF), signifying high right atrial pressure (RAP). Postnatal echocardiography confirmed morphology, Doppler & oval foramen restriction. Fetal pulmonary valvuloplasty (× 3) was performed percutaneously under ultrasound guidance at 21–30 weeks. Results: Three pregnancies with PAIVS were terminated. Six of the remaining 11 survived infancy, four with biventricular circulation. Fetal pulmonary valvuloplasty was offered in selected cases. Morphology was unsuitable in three. Two further monochorionic diamniotic twin pregnancies with good anatomy were excluded leaving three suitable for valvuloplasty. Valvuloplasty was successful in 2 cases but placental bleeding and bradycardia precipitated emergency delivery before valvuloplasty in the third. Eleven had high RAP (tricuspid regurgitation) with AREDF and hydrops in 1 case. The three with low RAP had the worst TV and PV growth velocities. At birth, median (95% CI) TV annulus Z score was −4.29 (−6.57 to −1.71). TV growth was significantly better in those with high RAP (−4.29 vs −6.00, p = 0.02) and oval foramen restriction. Conclusions: Fetuses with high RAP show the best RV growth, but may develop hydrops. AREDF may paradoxically be associated with better outcome, as fetal valvuloplasty may be most effective in those with high RAP.

P01.17: Changing pattern of advanced maternal age and prenatal diagnostic procedures in a tertiary referral centre, Australia

rupture of the membranes, the median gestational age at delivery was 36.1 weeks (range 34.1–39.1), with a median weight of 2215 gr (range 1750–2850). No single case of brain damage was detected among the survivors, as assessed by both clinical examination and imaging techniques. Conclusion: Although the number of cases is small, our initial results doing cord occlusion by bipolar forceps are comparable with those reported by others.

P01.01: Changing pattern of tertiary referrals for prenatal diagnosis in a major centre, Australia 1993–2002

Objective: To determine whether isolated choroid plexus cysts are a risk factor for trisomy 18 Methods: The cases with isolated choroid plexus cyst(s) were retrieved from our database from January 2001 to December 2004. Detailed ultrasonographic examination, maternal serum screening or genetic karyotyping was provided at the discretion of obstetricians who care for the pregnant women. All women were followed up through delivery. A retrospective chart review of the prenatal sonograms in the cases of trisomy 18 during the same period was also conducted. Results: One hundred fifty-six women had fetuses with isolated choroid plexus cyst(s). All fetuses with isolated choroid plexus cyst(s) either the normal karyotypes or the normal postnatal pediatric examination. There are 8 fetuses with trisomy 18 during the same period. Thirty-three percent of fetuses with trisomy 18 had choroid plexus cyst(s). All fetuses with trisomy 18 had structural anomalies. Conclusion: Isolated choroid plexus cyst was not associated with trisomy 18 in this study. All fetuses with trisomy 18 had structural anomalies which are obvious in antenatal scanning. These results indicate that the karyotyping of fetuses with isolated choroid plexus cyst(s) is not warranted.

The fetal tele-ultrasound project in Queensland.

Background: Prenatal Diagnosis is a rapidly evolving specialty. It is important to collect and understand the statistics for the service to plan for the future. Objective: To describe the patterns of tertiary referrals to a major centre over a ten-year period. Methods: Data from all patients referred to the Mater Centre for Maternal Fetal Medicine were prospectively collected and entered into a database. The indications for referral were categorised into: high risk (e.g. previous abnormal baby), ultrasound markers (e.g. Choroid plexus cyst), single fetal anomalies (e.g. gastroschisis), complex fetal anomalies (anomalies involving multiple systems), and third trimester complications. Diagnostic procedures performed were recorded, and pregnancy outcomes were sought from the initial site of referral. Results: Over the ten-year period, tertiary referrals to the Centre (patients not delivering in the Hospital) increased from 42 in 1993 to 1082 in 2002 (total 4814). Overall, the proportions of patients are: 38.5% high risk, 22% ultrasound markers, 21.4% single anomalies, 13% complex anomalies, and 5% third trimester complications. When divided into two 5-year periods, the rate of rise is most rapid for high risk (13.5 fold), followed by markers (6.8 fold), complex anomalies (3.7 fold), third trimester complications (3.1 fold), and single anomalies (2.7 fold). Overall, 787 invasive procedures were performed (16.3%). The rate of invasive procedures decreased from 21.4% to 15.6% (p < 0.0001) over the two 5-year periods. The proportion of procedures that were amniocentesis increased from 35% to 67% (p < 0.0001), and for CVS decreased from 46.9% to 30.9% (p < 0.001). 5% of pregnancies were terminated, 3% had a stillbirth, and 2% had neonatal deaths. Conclusions: The tertiary referral pattern for prenatal diagnosis has changed significantly. The pattern of invasive diagnostic procedures has also changed. Future service planning needs to take these patterns into consideration.