Both treatments aim to obtain a more normal balance of amniotic fluid between the twins, although only the laser treatment addresses the underlying anatomical defect. However, the two treatments have not previously been directly compared in a clinical trial.
This study will evaluate which treatment, laser photocoagulation or amnioreduction, results in better survival rates and better cardiac, neurological and developmental outcomes. In addition to studying health outcomes immediately after birth, the researchers also will assess the twins neurodevelopment at age 18 to 22 months.
Twelve medical centers throughout the United States will participate in the TTTS trial, sponsored by the National Institutes of Health. While all 12 centers perform amnioreduction, only two, The Childrens Hospital of Philadelphia and the University of California, San Francisco, also perform fetoscopic laser coagulation. Those two institutions also are the only centers in the world offering comprehensive treatments in fetal surgery.
Enrollment for the multicenter TTTS study began in March 2002 and is scheduled to continue through March 2005. Throughout the country, researchers expect to recruit a total of 150 patients for the trial, of which approximately half will be recruited by The Children's Hospital of Philadelphia.
Because of the requirements of randomized studies, each mother who enrolls in the trial will be randomly assigned to either amnioreduction treatment or laser treatment. Participating centers will not perform the laser treatment outside of the clinical trial.