Systematic ultrasound assessment and surgical treatment of twin-twin transfusion syndrome

• Rubén A. Quintero
• E.V. Kontopoulos

Abstract

Twin-twin transfusion syndrome (TTTS) occurs in approximately 5 to 10% of monochorionic twins [1]. Monochorionic twins themselves occur in approximately 0,7% of all pregnancies [2]. Therefore, TTTS occurs in approximately 0,07% of all pregnancies. This amounts to approximately 2800 pregnancies in United States per year affected with TTTS [3]. The disease is thought to occur secondary to an imbalance in the transfer of blood between two monochorionic twins through placental vascular anastomoses [4]. Although proof of this etiology has proven somewhat elusive, a wealth of indirect evidence does suggest this to be the fundamental mechanism for the development of this condition [5–7]. The unbalanced exchange of blood between two monochorionic fetuses results in a set of hemodynamic alterations that ultimately place the pregnancy at risk of being lost [8, 9]. The recipient twin develops polyuria and polyhydramnios and is presumed to be hypertensive. The donor twin develops anuria and oligohydramnios and is presumed to be hypotensive. Loss of the pregnancy may result either from preterm delivery or miscarriage or demise of one or both fetuses. Untreated, twin-twin transfusion syndrome results in pregnancy loss rate is of approximately 95% [10].

Significant achievements have been made in both the understanding as well as in the evaluation and treatment of patients with TTTS. Included in those achievements are standardization of the diagnostic criteria, the development of a staging system to assess the severity of the disease, the development of an effective laser surgical technique to eliminate the vascular anastomoses, the scientific demonstration of this superiority of laser therapy over serial amniocentesis and continuous improvements in the actual performance of the laser surgery. The purpose of this chapter is to review the sonographic assessment of patients suspected of having TTTS and their surgical management.

Editorial office of journal «Obstetrics and gynecology: news, views, education» No. 1, 2014 expresses gratitude to authors for permission of the publication.

Keywords:twin-twin transfusion syndrome, ultrasound, surgical treatment, monochorionic twins