Diagnose of placenta accreta
Patients diagnosed as PAS overlying the cesarean scar were included.
A thorough perioperative
sonography was performed to determine the invasion of the placenta, the
length and shape of cervix. Cervical involvement was determined when the
placenta covered the internal os and blood flow could be detected inside
the shortened cervix canal (length <2 cm). Those with two or
more signs of the following were considered to be severe and
preoperative aortic balloon was suggested: two or more times of previous
CS; cervical involvement; complete placenta previa; placental lacunae
and turbulence, and loss of myometrial interface with width
> 3 cm; bladder wall interruption and uterovescical
hypervascularity.
The severity of placenta invasion was evaluated intraoperatively.
Placenta accreta: manual removal of placenta required; Placenta increta:
part of the placenta need cut with sissors, the lefted uterine wall was
rather thinner than those around; Placenta percreta: placenta tissue
seen to have invaded through the serosa of the uterus with
hypervascularity, or a clear surgical plane cannot be identified between
the bladder and uterus. Placenta increta/percreta with extension over
1/3 of the placenta, or with cervical involvement was determined to be
severe.