Second trimester placenta percreta presenting as acute abdomen

Uterine body placenta accreta spectrum: A detailed literature review

Placenta accreta spectrum (PAS) is a major obstetrical problem whose incidence is rising. Current guidelines recommend screening of all women with placenta previa and risk factors for PAS between 20 and 24 weeks. Risk factors, diagnosis, and management of previa PAS are well established, but an apparently normal location of the placenta does not exclude PAS. Literature data are scarce on uterine body PAS, which carries a high risk of maternal and neonatal adverse outcome, but is still easily missed on prenatal ultrasound. We conducted a comprehensive review to identify possible risk factors, clinical presentations, and diagnostic modalities of uterine PAS. A total of 133 cases were found during a 70-year period (1949-2019). The vast majority of them presented with signs of uterine rupture, even prior to the viability threshold of 24 weeks (up to 45%). Major risk factors included previous cesarean delivery, uterine curettage, uterine surgery, Asherman's syndrome, manual removal of the placenta, endometritis, high parity, young maternal age, in vitro fertilization, radiotherapy, uterine artery embolization, and uterine leiomyoma. Diagnosis was pre-symptomatic in only 3% of cases. Future studies should differentiate between previa PAS and uterine body PAS.

Placenta percreta evaluated by MRI: correlation with maternal morbidity

PURPOSE

The purpose of this study was to evaluate the capability of MRI in depicting the topography of placenta percreta (PP) and to further explore the correlation between invasion topography and maternal outcomes.

METHODS

55 patients with histologically or surgically confirmed PP were included in this retrospective study. Two senior radiologists evaluated the topography of PP based on MR images: the invasion topography was depicted as S1, S2, parametrial, bladder, and cervical invasion. The correlation between invasion topography and maternal outcomes was analyzed using Chi-square statistic.

RESULTS

MRI showed high sensitivity and specificity in delineating the invasion topography of PP (ranging from 87.5 to 100%). MRI had 100% specificity for predicting the parametrial, bladder, and cervical invasion. The rate of cesarean hysterectomy, ureteral injuries and ICU administration, and the amount of blood transfusions in PP with S2 invasion were higher than S1 invasion (P < 0.05). In addition, all patients with bladder invasion (8/8) received partial bladder resection by urologists. All the patients with S2 parametrial invasion (12/12) or cervical invasion (9/9) underwent cesarean hysterectomy.

CONCLUSION

MRI was capable in predicting the invasion topography of PP patients. Moreover, PP patients with S2, parametrial, bladder or cervical invasion had more severe maternal morbidity.