Twin venous anastomosis

Twins are divided into monozygotic twins and twins. Single egg twins are divided into double amniotic sac double chorionic twins, double amniotic sac single chorionic twins and single amniotic sac single chorionic twins. Blood circulation includes arterial-arterial, vein-venous, arterial-venous anastomosis. Anastomosis of blood vessels can be divided into superficial and deep. Superficial anastomosis refers to the anastomosis of large blood vessels on the surface of the fetal surface of the placenta. Most of them are arterial-arterial anastomosis, and a few are direct-venous anastomosis. On the fetal surface of a few single chorionic twin placenta, both anastomoses are present. The deep anastomosis is located in one or more placental lobes adjacent to the placenta of the two fetuses. Although there are multiple anastomoses through the capillaries, there is no direct arterial or venous anastomosis, but the blood is from one fetus Flowing to another fetus, Schaty (1900) calls it the "third cycle." A manifestation of twin blood transfusion syndrome during twin vein anastomosis. Twin blood transfusion syndrome is caused by a single zygote, single chorion, double amniotic sac twins, and a fetus (blood donor) delivers blood to another fetus (blood recipient) through the placenta imbalanced vascular anastomosis network in the official cavity A series of pathophysiological changes and clinical symptoms are serious complications of twin or multiple pregnancy, which were first discovered and proposed by Hedite l941. The disease can be divided into two types, acute and chronic, which are usually referred to as chronic. The incidence of this disease in single chorionic twins is about 10% to 15%, and the prognosis is poor. If left untreated, the mortality rate can be as high as 80% to 9 ()%. Survivors also have a higher incidence of neurological diseases.