Risk of Neurodevelopmental Sequelae Low in TTTS

A multiyear study at The Children's Hospital of Philadelphia looked at the neurocognitive effects of twin-twin transfusion syndrome (TTTS) in monochorionic twins who underwent in utero laser surgery.

TTTS occurs before birth in about 10 to 15 percent of monochorionic twins who share one placenta but each have their own amniotic sac. The shared placenta contains blood vessels connecting both fetuses, and TTTS results from a blood flow imbalance. Without intervention, TTTS results in the death of one or both fetuses in 80 to 100 percent of cases.

Nahla Khalek, MD, MPH, FACOG, a CHOP maternal-fetal medicine and clinical genetics specialist who led the study, and colleagues analyzed two-year neurodevelopmental outcomes in 29 pairs of twins with TTTS who underwent selective laser photocoagulation of placental anastomoses in utero at CHOP between 2009 and 2011. This minimally invasive procedure uses a laser fiber inserted through a fetoscope to identify and disconnect all of the identifiable connecting blood vessels, allowing for redistribution and normalization of blood flow to each fetus.

The researchers assessed the children's cognitive, language, behavior, and motor skills using three standard neurodevelopmental tests.

"Overall, there were high rates of normal neurodevelopmental outcomes in these children at age 2," Dr. Khalek said. She added that future research should follow neurodevelopmental outcomes as TTTS survivors reach school age. "This data will allow us to further stratify patients and guide us in counseling parents about longer-term neurodevelopmental outcomes for their children."

Laura and Adam Epstein, whose daughters Rose and Madeline were treated for TTTS by fetal surgeons at CHOP in 2011, and the Conway Family Foundation, a philanthropic organization run by the twins' grandparents, provided funding for this study.

Dr. Khalek presented the study results at the annual meeting of the Society for Maternal-Fetal Medicine in New Orleans held Feb. 3-8.