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Published on: September 5, 2011
Middle cerebral artery Doppler velocity discordance in the first 2 weeks after laser for twin-twin transfusion
Elena R Taylor1, Jena L Miller2, Christina Rivera1
1Department of Gynecology and Obstetrics, The Johns Hopkins Center for Fetal Therapy, Johns Hopkins University School of Medicine, Baltimore, MD (Taylor, Miller, Rivera, Johnson, Kush, Baschat, and Rosner); Johns Hopkins University, Baltimore, MD (Taylor and Rivera).
Background:
Postoperative middle cerebral artery peak systolic velocity assessment after laser surgery for twin-twin transfusion syndrome is used to monitor for postlaser twin anemia polycythemia sequence. However, the significance of early middle cerebral artery peak systolic velocity Doppler discordance after laser surgery is not well established.
Objective:
This study aimed to evaluate the significance of early postoperative middle cerebral artery Doppler discordance within 2 weeks after laser surgery for twin-twin transfusion syndrome.
Study Design:
Patients were stratified by the presence of middle cerebral artery peak systolic velocity discordance on postoperative days 1 and 2 and postoperative weeks 1 and 2 after laser surgery for twin-twin transfusion syndrome. Middle cerebral artery peak systolic velocity discordance was defined as an intertwin difference of ≥0.5 multiples of the median. The composite adverse outcomes included postlaser twin anemia polycythemia sequence, fetal demise after postoperative day 1, and abnormal postlaser brain findings.
Results:
Postoperative middle cerebral artery peak systolic velocity discordance of ≥0.5 multiples of the median occurred in 35.4% of patients on postoperative day 1, 24.7% of patients on postoperative day 2, 16.8% of patients on postoperative week 1, and 10.5% of patients on postoperative week 2. Postoperative middle cerebral artery discordance was often associated with increases in recipient middle cerebral artery multiples of the median. Although middle cerebral artery discordance was transient in most patients, our composite outcome was approximately twice as prevalent in patients with early middle cerebral artery Doppler discordance. Early middle cerebral artery Doppler discordance after laser surgery did not correlate with birth outcomes, such as gestational age at delivery or survival. Of note, prevalence data may be limited by patient attrition across time points.
Conclusion:
Early postoperative middle cerebral artery discordance is common and typically resolves within 2 weeks after laser surgery. Despite being associated with higher rates of the composite outcome, early middle cerebral artery discordance did not significantly affect birth or survival outcomes. El resumen está disponible en Español al final del artículo.

