Ultrasonographic Diagnosis of Twin-to-Twin Transfusion Syndrome

Abstract

Introduction: Twin-twin transfusion syndrome (TTTS) is a typical complication of monochorionic twin pregnancies (MCTP). Placental vessels that communicate in the chorionic plate between donor and recipient, are responsible for the imbalance of blood flow. Circulatory imbalance causes hypovolemia in donor and hypervolemia in recipient fetus. In a typical case, recipient fetus develops polyhydramnios, weight gain, cardiomegaly and hydrops fetalis. In contrast, donor fetus develops oligohydramnios and fetal growth restriction. Aim: The objective of this review is to evaluate in detail the main diagnostic aspects and add other important data for diagnosis of TTTS. Scientific bases: The main diagnostic event for this condition is based on the ultrasonographic discovery of oligohydramnios-polyhydramnios sequence. Other useful elements for diagnosis, staging and prognosis are fetal urinary bladder visualization, urinary bladder volumen measurements, edema of subcutaneous and/or generalized tissue edema, Doppler flow velocity waves and cardiac evaluation. Conclusions: Considerations regarding diagnosis of TTTS make it possible to emphasize that role of physicians treating patients with MCTP is to identify ultrasound sequence of oligohydramnios-polyhydramnios. Other ultrasonographic fetal data as fetal urinary bladder visualization, urinary bladder volumen measurements, edema of subcutaneous and/or generalized tissue edema, Doppler flow velocity waves and cardiac evaluation; may help diagnosis, staging and prognosis of TTTS. It is their responsibility to accurately assess severity, therapeutic possibilities and prognosis. Key Points

Doppler Finding, Cardiovascular Function Assessment, and Fetuses’ Survival Following the Fetoscopic Laser in Twin-to-Twin Transfusion Syndrome

“…7 For staging the severity of this phenomenon, the assessment of arterial and venous Doppler patterns along with bladder filling is very helpful. 8 Nowadays, selective laser photocoagulation of communicating vessels (SLPCV) between twins is the selective therapeutic option for TTTS with high successfulness, maintaining the longterm survival of infants. 9 According to the literature, this treatment approach could lead to long-term survival of up to 65% in both fetuses and up to 88% in a single fetus.…”