Fetal brain-sparing after laser surgery for twin-twin transfusion syndrome appears associated with two-year neurodevelopmental outcomes

Objective: The cerebroplacental ratio (CPR) is a semi-quantitative marker for fetal brain-sparing. Our purpose was to measure the CPR at the time of treatment with selective laser photocoagulation of communicating vessels in gestations with twin-twin transfusion syndrome (TTTS) to test its association with neurological outcomes at approximately 2years. Methods: One-hundred children treated for TTTS with laser surgery underwent neurodevelopmental assessment at age 2years (within 6weeks) via the Battelle Developmental Inventory 2nd Edition (BDI-2). The CPR was obtained 24h before and after laser surgery. An abnormal CPR was categorically defined at <1.0. Multilevel linear regression was used to evaluate associations between CPR and neurodevelopment as assessed by the BDI-2. Results: Ninety-nine children had data available for analysis: 55 (56%) had normal CPR prior to laser surgery, and 62 (63%) had normal CPR following surgery. Post-laser CPR <1.0 was a risk factor for lower BDI-2 scores at age 2years [98.1 (SD 11.5) vs 103.4 (SD 12.3) vs β=-0.23, p=0.01]; this relationship remained significant after controlling for pre-surgical CPR and Quintero stage (adjusted β=-0.25, p=0.01). Conclusions: In this population, an abnormal CPR was associated with poorer 2-year neurodevelopmental outcomes.