The Utility of MRI Scoring to Predict Neurodevelopmental Outcomes in Survivors of Twin-to-Twin Transfusion Syndrome

Twins who share a placenta but have two separate sacs of amniotic fluid (monochorionic-diamniotic) are at risk of developing twin-to-twin transfusion syndrome (TTTS). TTTS results from anastomoses in the placenta that lead to unequal sharing of blood, causing abnormal blood flow to the twins. The donor twin may have low fluid levels, poor growth, and anemia. The recipient twin can have high fluid levels, high red blood cell counts, heart failure, and hydrops. Having TTTS, especially if there is demise of one twin or if disease is severe enough to warrant laser photocoagulation of the anastomotic sites, puts the surviving fetuses at risk for brain injury due to hypoxia, ischemia, or reperfusion injuries. Magnetic Resonance Imaging (MRI) is superior to ultrasound at detecting subtle cerebral injuries. An MRI scoring scale has been developed for use in very low birth weight infants that has been shown to correlate with neurodevelopmental outcomes, but it has not been tested in this patient population. Our center's guidelines recommend fetal MRI prior to intervention, at 32 weeks gestational age, and on the infants at term corrected gestational age. Infants who were treated for TTTS in utero are seen in Nursery Follow-up Clinic at 4 months of age, 8 months of age, and for Bayley Scales evaluations at 15-18 months of age and at 2-3 years of age. The purpose of this study is to correlate brain MRI score with neurodevelopmental outcomes in survivors of TTTS that have either required fetal surgical intervention or had demise of their cotwin. The investigators predict that more severe white and gray matter injury as determined by the Woodward/Inder grading scale will be positively associated with worse neurodevelopmental outcomes.