OC08.03: Placenta accreta spectrum: prediction of pathological grade by ultrasound examination

Investigate the ultrasound diagnostic signs of placenta accreta spectrum (PAS) between two groups divided by the severity of the histopathological grading. Secondary outcome was blood loss, gestational age at birth, hysterectomy and use of the devascularisation operations. Retrospective analysis of 30 PAS cases referred to our clinic in the period 2018-2023. The analysis compared ultrasound signs: myometrial thinning, loss of the clear zone, placental bulging, placental lacunaes and uterovesical hypervascularity. Cases were divided by the histopathological grading system in two groups. Group A was characterised with a histopathological grade 3A and higher. Group B with a grade 2 and lower. The prenatal ultrasound examination was performed by ultrasound experts in PAS imaging. 16/30 cases were present in group A, respectively 14 cases in group B. Myometrial thinning was present in 16 cases in group A, respectively in 3 cases in the group B (100%/21.4%, p <0.001). Loss of the clear zone in 13 cases in the group A and 2 cases in the group B (81.3.%/14.3%, p < 0.001). Placental lacunaes 14 cases in the group A and 9 cases in the group B (87.5.%/64.3%, p = 0.134). Placental bulging in 11 cases in group A, and none in the group B (68.8%/0%, p = 0.000). Uterovesical hypervascularity in 11 cases in the group A and 2 in the group B (68.8.%/14.3.%, p = 0.003). Blood loss median 2250ml in group A and 600ml in group B. Ligation of hypogastric arteries was performed in 12 cases in the group A and in one case in the group B. Hysterectomy was performed in all patients in the group A and in 2 patients in the group B. Median of the gestational age in group A was 34.4 weeks and 35.5. weeks in group B. Myometrial thinning and loss of the clear zone has most significant diference in the prediction of the myometrial invasion in placenta accreta spectrum. Patients with severe histopathological grade are in the risk of higher blood loss, hysterectomy and need of the devascularization procedures.