title: Fetoscopic treatment for discordant twins.
abstract: OBJECTIVE
  In rare instances in monochorionic twin pregnancies, one twin can have a discordant anomaly (eg, cystic hygroma). If this twin dies in utero, neurologic injury and death can occur in the surviving cotwin. To protect the normal twin, the authors developed an approach to separate the circulations and ablate the umbilical cord of the abnormal twin.
  
  
  METHODS
  From September 1998 to February 2001, 6 cases of discordant anomalous twins were diagnosed by prenatal ultrasound scan in which the anomaly was lethal or parents desired prenatal termination for this abnormal twin. All underwent surgical intervention with gestational ages varying from 19 to 24 weeks.
  
  
  RESULTS
  Depending on cord insertion site and placental anatomy, blood flow was interrupted to the anomalous fetus by either radiofrequency ablation (RFA; 2 cases), cord transection (1 case), or cord transection after laser ablation of communicating vessels (3 cases). Fetal death occurred in one normal twin 4 days postoperatively. Average age at delivery for the 5 surviving fetuses was 34.5 weeks' gestation. On follow-up, all surviving infants are neurologically intact.
  
  
  CONCLUSIONS
  An otherwise normal monochorionic twin threatened by an anomalous cotwin can be salvaged successfully with a strategy tailored to interrupt the vascular connections between the 2 twins.
authors.affiliation: Division of Pediatric Surgery, Department of Surgery, Fetal Treatment Center, University of California, San Francisco, CA, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Sydorak
authors.forename: V
authors.initials: V
authors.lastname: Feldstein
authors.forename: G
authors.initials: G
authors.lastname: Machin
authors.forename: K
authors.initials: K
authors.lastname: Tsao
authors.forename: S
authors.initials: S
authors.lastname: Hirose
authors.forename: H
authors.initials: H
authors.lastname: Lee
authors.forename: D L
authors.initials: DL
authors.lastname: Farmer
authors.forename: M R
authors.initials: MR
authors.lastname: Harrison
authors.forename: C T
authors.initials: CT
authors.lastname: Albanese
mesh_terms: D000015:Abnormalities, Multiple / Q000000981:diagnostic imaging / Q000517:prevention & control*; D000328:Adult; D017115:Catheter Ablation; D036861:Delivery, Obstetric / Q000379:methods; D004200:Diseases in Twins / Q000175:diagnosis / Q000517:prevention & control*; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging / Q000517:prevention & control*; D005332:Fetoscopy / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D007902:Length of Stay; D011247:Pregnancy; D011256:Pregnancy Outcome; D016879:Salvage Therapy / Q000379:methods; D016216:Ultrasonography, Prenatal; D014470:Umbilical Cord / Q000601:surgery*