Original Paper Received: September 10, 2014 Accepted after revision: December 29, 2014 Published online: April 15, 2015
Fetal Diagn Ther DOI: 10.1159/000374109
Endoscopic Placental Laser Coagulation in Monochorionic Diamniotic Twins with Type II Selective Fetal Growth Restriction Gergana Peeva Sarah Bower Laszlo Orosz Petya Chaveeva Ranjit Akolekar Kypros H. Nicolaides Harris Birthright Research Centre of Fetal Medicine, King’s College Hospital, London, UK
Abstract Objective: To determine predictors of survival in monochorionic diamniotic twins with selective fetal growth restriction type II (sFGR-II), with or without twin-to-twin transfusion syndrome (TTTS), treated by endoscopic placental laser coagulation. Methods: Laser surgery was performed at 20 (15– 27) weeks’ gestation in 405 cases of sFGR-II with and 142 without coexisting TTTS. Multivariable logistic regression analysis was performed to determine significant predictors of survival to discharge from hospital. Results: There was survival of the small twin in 216 (39.5%) and of the large twin in 379 (69.3%) cases. Significant predictors of survival of both the small and larger twin were ductus venosus Doppler findings in the small twin, gestational age at laser and cervical length, but not the presence of TTTS or Doppler findings in the large twin. Conclusions: In sFGR-II, survival after laser surgery is primarily dependent on the condition of the small twin. © 2015 S. Karger AG, Basel
© 2015 S. Karger AG, Basel 1015–3837/15/0000–0000$39.50/0 E-Mail [email protected] www.karger.com/fdt
Introduction
Selective fetal growth restriction (sFGR), defined by the presence of a ≥25% discordance in estimated weight between the fetuses, is observed in 12% of monochorionic diamniotic (MCDA) twin pregnancies [1]. The condition is subdivided into types I, II and III according to the Doppler finding of the end diastolic flow (EDF) in the umbilical artery of the small fetus, which is normal in type I, absent or reversed (AREDF) in type II or intermittent AREDF in type III [2]. Some cases of sFGR are complicated by twin-to-twin transfusion syndrome (TTTS), defined by marked discordance in amniotic fluid volume with the deepest vertical pool of ≤2 cm in one sac and ≥8 cm before 20 weeks and >10 cm after 20 weeks in the other sac [3, 4]. In TTTS, the severity of the disease is classified as stage I if the Doppler findings in the umbilical artery and ductus venosus of both fetuses are normal and the bladder of the donor is visible, stage II with normal Doppler findings but not visible bladder, stage III with abnormal Doppler findings in either twin and stage IV with presence of ascites or hydrops in either twin [3]. In the management of TTTS, endoscopic laser coagulation of the inter-twin communicating placental vessels Prof. K.H. Nicolaides Harris Birthright Research Centre for Fetal Medicine King’s College Hospital, Denmark Hill London SE5 9RS (UK) E-Mail kypros @ fetalmedicine.com
Downloaded by: Freie Universität Berlin 130.133.8.114 - 5/11/2015 6:52:18 AM
Key Words Monochorionic twins · Selective fetal growth restriction · Twin-to-twin transfusion syndrome · Endoscopic laser coagulation
Table 1. Pregnancy characteristics in monochorionic twin pregnancies with sFGR-II following treatment with endoscopic laser surgery in fetuses that survived and those that did not survive
Characteristic
Smaller fetus
Discordance Coexisting twin-to-twin transfusion Yes No Umbilical artery end diastolic flow Positive Negative Reversed Ductus venosus a-wave (n = 516) Positive Negative/reversed Year of laser – 1992 Placental position Anterior Posterior Gestation at laser, weeks Cervical length, mm Gestation at outcome, weeks Birth weight, g
Larger fetus
alive (n = 216)
dead (n = 331)
alive (n = 379)
dead (n = 168)
32.1 (28.1 – 38.3)*
35.4 (29.9 – 42.4)
33.8 (28.7 – 41.6)
34.5 (30.0 – 39.7)
161 (74.5) 55 (25.5)
244 (73.7) 87 (26.3)
283 (74.7) 96 (25.3)
122 (72.6) 46 (27.4)
– 202 (93.5) 14 (6.5)*
– 282 (85.2) 49 (14.8)
340 (89.7) 37 (9.8) 2 (0.5)
146 (86.9) 21 (12.5) 1 (0.6)
165 (80.5%) 40 (19.5%)* 15 (10 – 19)*
170 (54.7%) 141 (45.3%) 14 (8 – 18)
277 (76.9%) 83 (23.1%) 15 (10 – 18)*
116 (74.4%) 40 (25.6%) 13 (7 – 18)
108 (50.0) 108 (50.0) 20.4 (18.3 – 23.1)* 31 (27 – 36)* 32.0 (29.8 – 34.2)* 1,200 (860 – 1,710)
165 (49.8) 166 (50.2) 19.7 (17.6 – 22.0) 30 (25 – 34) 21.7 (19.1 – 25.0) –
190 (50.1) 189 (49.9) 20.1 (18.0 – 22.7) 31 (27 – 35)* 32.1 (29.9 – 34.6)* 1,674 (1,287 – 2,100)
83 (49.4) 85 (50.6) 19.7 (17.6 – 21.9) 29 (22 – 35) 22.2 (19.8 – 25.4) –
Values are presented as median (interquartile range) or n (%). * p < 0.01.
Patients and Methods This study comprised all cases of MCDA twins complicated by sFGR-II, with and without coexisting TTTS, which were treated by endoscopic laser coagulation of the inter-twin communicating placental vessels in our fetal medicine centre between 1992, when
2
Fetal Diagn Ther DOI: 10.1159/000374109
we first introduced endoscopic laser surgery [4], and April 2014. Umbilical cord occlusion was not a treatment option for sFGR or TTTS in our centre. In total, there were 556 cases that fulfilled the entry criteria, but 9 were excluded from further analysis because they were lost to follow-up. The study population comprised 547 cases of sFGR-II, including 405 (74%) with coexisting TTTS and 142 (26%) without TTTS. The TTTS was stage III in 385 (95%) cases and stage IV in 20 (5%). Gestational age was determined by ultrasound measurements of the larger twin, including crown-rump length at
Fetal Diagn Ther DOI: 10.1159/000374109
Endoscopic Placental Laser Coagulation in Monochorionic Diamniotic Twins with Type II Selective Fetal Growth Restriction Gergana Peeva Sarah Bower Laszlo Orosz Petya Chaveeva Ranjit Akolekar Kypros H. Nicolaides Harris Birthright Research Centre of Fetal Medicine, King’s College Hospital, London, UK
Abstract Objective: To determine predictors of survival in monochorionic diamniotic twins with selective fetal growth restriction type II (sFGR-II), with or without twin-to-twin transfusion syndrome (TTTS), treated by endoscopic placental laser coagulation. Methods: Laser surgery was performed at 20 (15– 27) weeks’ gestation in 405 cases of sFGR-II with and 142 without coexisting TTTS. Multivariable logistic regression analysis was performed to determine significant predictors of survival to discharge from hospital. Results: There was survival of the small twin in 216 (39.5%) and of the large twin in 379 (69.3%) cases. Significant predictors of survival of both the small and larger twin were ductus venosus Doppler findings in the small twin, gestational age at laser and cervical length, but not the presence of TTTS or Doppler findings in the large twin. Conclusions: In sFGR-II, survival after laser surgery is primarily dependent on the condition of the small twin. © 2015 S. Karger AG, Basel
© 2015 S. Karger AG, Basel 1015–3837/15/0000–0000$39.50/0 E-Mail [email protected] www.karger.com/fdt
Introduction
Selective fetal growth restriction (sFGR), defined by the presence of a ≥25% discordance in estimated weight between the fetuses, is observed in 12% of monochorionic diamniotic (MCDA) twin pregnancies [1]. The condition is subdivided into types I, II and III according to the Doppler finding of the end diastolic flow (EDF) in the umbilical artery of the small fetus, which is normal in type I, absent or reversed (AREDF) in type II or intermittent AREDF in type III [2]. Some cases of sFGR are complicated by twin-to-twin transfusion syndrome (TTTS), defined by marked discordance in amniotic fluid volume with the deepest vertical pool of ≤2 cm in one sac and ≥8 cm before 20 weeks and >10 cm after 20 weeks in the other sac [3, 4]. In TTTS, the severity of the disease is classified as stage I if the Doppler findings in the umbilical artery and ductus venosus of both fetuses are normal and the bladder of the donor is visible, stage II with normal Doppler findings but not visible bladder, stage III with abnormal Doppler findings in either twin and stage IV with presence of ascites or hydrops in either twin [3]. In the management of TTTS, endoscopic laser coagulation of the inter-twin communicating placental vessels Prof. K.H. Nicolaides Harris Birthright Research Centre for Fetal Medicine King’s College Hospital, Denmark Hill London SE5 9RS (UK) E-Mail kypros @ fetalmedicine.com
Downloaded by: Freie Universität Berlin 130.133.8.114 - 5/11/2015 6:52:18 AM
Key Words Monochorionic twins · Selective fetal growth restriction · Twin-to-twin transfusion syndrome · Endoscopic laser coagulation
Table 1. Pregnancy characteristics in monochorionic twin pregnancies with sFGR-II following treatment with endoscopic laser surgery in fetuses that survived and those that did not survive
Characteristic
Smaller fetus
Discordance Coexisting twin-to-twin transfusion Yes No Umbilical artery end diastolic flow Positive Negative Reversed Ductus venosus a-wave (n = 516) Positive Negative/reversed Year of laser – 1992 Placental position Anterior Posterior Gestation at laser, weeks Cervical length, mm Gestation at outcome, weeks Birth weight, g
Larger fetus
alive (n = 216)
dead (n = 331)
alive (n = 379)
dead (n = 168)
32.1 (28.1 – 38.3)*
35.4 (29.9 – 42.4)
33.8 (28.7 – 41.6)
34.5 (30.0 – 39.7)
161 (74.5) 55 (25.5)
244 (73.7) 87 (26.3)
283 (74.7) 96 (25.3)
122 (72.6) 46 (27.4)
– 202 (93.5) 14 (6.5)*
– 282 (85.2) 49 (14.8)
340 (89.7) 37 (9.8) 2 (0.5)
146 (86.9) 21 (12.5) 1 (0.6)
165 (80.5%) 40 (19.5%)* 15 (10 – 19)*
170 (54.7%) 141 (45.3%) 14 (8 – 18)
277 (76.9%) 83 (23.1%) 15 (10 – 18)*
116 (74.4%) 40 (25.6%) 13 (7 – 18)
108 (50.0) 108 (50.0) 20.4 (18.3 – 23.1)* 31 (27 – 36)* 32.0 (29.8 – 34.2)* 1,200 (860 – 1,710)
165 (49.8) 166 (50.2) 19.7 (17.6 – 22.0) 30 (25 – 34) 21.7 (19.1 – 25.0) –
190 (50.1) 189 (49.9) 20.1 (18.0 – 22.7) 31 (27 – 35)* 32.1 (29.9 – 34.6)* 1,674 (1,287 – 2,100)
83 (49.4) 85 (50.6) 19.7 (17.6 – 21.9) 29 (22 – 35) 22.2 (19.8 – 25.4) –
Values are presented as median (interquartile range) or n (%). * p < 0.01.
Patients and Methods This study comprised all cases of MCDA twins complicated by sFGR-II, with and without coexisting TTTS, which were treated by endoscopic laser coagulation of the inter-twin communicating placental vessels in our fetal medicine centre between 1992, when
2
Fetal Diagn Ther DOI: 10.1159/000374109
we first introduced endoscopic laser surgery [4], and April 2014. Umbilical cord occlusion was not a treatment option for sFGR or TTTS in our centre. In total, there were 556 cases that fulfilled the entry criteria, but 9 were excluded from further analysis because they were lost to follow-up. The study population comprised 547 cases of sFGR-II, including 405 (74%) with coexisting TTTS and 142 (26%) without TTTS. The TTTS was stage III in 385 (95%) cases and stage IV in 20 (5%). Gestational age was determined by ultrasound measurements of the larger twin, including crown-rump length at
