Histological Appearance of Placental Solomonization in the Treatment of Twin–Twin Transfusion Syndrome

Abstract

Background Placental laser equatorialization or “solomonization” during treatment for twin–twin transfusion syndrome (TTTS) is associated with improved pregnancy outcomes. Concern exists, however, about the extent of placental injury caused by the technique, and of its ability to create “dichorionization,” or complete separation of the fetal vascular circuits.

Case Study A “solomonized” placenta was histologically examined for depth of cell damage. Solomonization produces complete devascularization of the chorionic plate, but has minimal effect on the underlying villi. The median depth of the effect was 2,823 µm, or < 3 mm.

Conclusion Solomonization produces complete devascularization of the chorionic plate, but has little effect on the underlying villi. “Dichorionization” is therefore not achieved. Ongoing surveillance of treated pregnancies is warranted.

Keywords

laser photocoagulation - placental equatorialization - Solomon technique - twin–twin transfusion syndrome

Note

The University of Pittsburgh Institutional Review Board approved this study. Teaching points: (1) Placental laser equatorialization, or solomonization, produces full-thickness devitalization of the vascular equator; (2) solomonization has little effect on the underlying villi; and (3) solomonization does not produce dichorionization.

• References

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