title: Selective versus non-selective laser photocoagulation of placental vessels in twin-to-twin transfusion syndrome.
abstract: 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.
  
  
  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 > or = 8 cm maximum vertical pocket (MVP) in the recipient twin and oligohydramnios of < or = 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.
authors.affiliation: Florida Institute for Fetal Diagnosis and Therapy, St. Joseph's Women's Hospital, Tampa, Florida, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Quintero
authors.forename: C
authors.initials: C
authors.lastname: Comas
authors.forename: P W
authors.initials: PW
authors.lastname: Bornick
authors.forename: M H
authors.initials: MH
authors.lastname: Allen
authors.forename: M
authors.initials: M
authors.lastname: Kruger
mesh_terms: D001163:Arteriovenous Anastomosis / Q000601:surgery*; D005260:Female; D005330:Fetofetal Transfusion / Q000601:surgery*; D005332:Fetoscopy; D006801:Humans; D008028:Light Coagulation; D010920:Placenta / Q000098:blood supply*; D011247:Pregnancy