Aims and objectives
Placenta Accreta Spectrum (PAS) is the general term applied to abnormal adherence of the placental trophoblast to the uterine placenta.
The spectrum includes the attachment of the placenta to myometrium without intervening of decidua (placenta accreta),
the invasion of myometrium (placenta increta) and infiltration of the surrounding organs through the uterine serosa (placenta percreta).
Previous cesarean section and placenta previa are the two most important risk factors.
Pregnancies with invasive placenta are more likely to have preterm delivery and develop potentially fatal massive bleeding.
Methods and materials
Fifty consecutive parturientes from June 2014 to May 2017 were retrospectively selected.
Inclusion criteria were: placenta previa and/or ultrasound suspect of PAS,availability of MR imaging and surgery outcome/pathology.
Among the fifty potentially eligible patients,
12 were excluded because of parturients moved to other institutions before the delivery (n=9),
emergency delivery before MR exam (n=1),
vaginal delivery (n=1),
absence of placenta previa on MRI (n=1).
a total of 38 patients (median age of 36 years; range 21-44) were included (Fig.1).
All the MR exams were...
Out of 38 patients,
12 (31,6%) were diagnosed with PAS and 26 (68,4%) did not show PAS.
When considering the clinical outcome,
8 patients (21,1%) showed poor outcome and 30 good outcome (Figs.
The Discriminant Analysis provided two specific predictive models,
one for the PAS diagnosis and one for the clinical outcome prediction.
Percretism signs were found to be the most important predictive variable,
both considering the PAS and the clinical outcome prediction.
the predictive model selected two MR signs for the...
The diagnostic performance of MRI is higher when the target is the clinical outcome prediction rather than the PAS diagnosis.
the combination of two MR findings,
percretism signs and myometrial thinning for clinical outcome,
and percretism sign and intraplacental abnormal vascularity for PAS,
reached a higher diagnostic accuracy compared to individual findings.
Department of Neuroscience,
Imaging and Clinical Sciences,“G.
Placenta Accreta Spectrum.
N Engl J Med,
Real increasing incidence of hysterectomy for placenta accreta
following previous caesarean section.
Eur J Obstet Gynecol Reprod Biol,
Committee on Obstetric,
Committee opinion no.
529: placenta accreta.
Diagnosis and management of placenta
percreta: a review.
Obstet Gynecol Surv,