Sonographic findings of placental lacunae and the prediction of adherent placenta in women with placenta previa totalis and prior Cesarean section.

Abstract

OBJECTIVE: To investigate the value of transvaginal sonographic findings of intraplacental lacunae for predicting adherent placenta and clinical outcome in patients with placenta previa totalis and a history of Cesarean section. METHODS: Fifty-one patients with placenta previa totalis diagnosed by transvaginal sonography and with a history of Cesarean section who delivered at our hospital were included in the study. The sonographic findings of intraplacental lacunae were classified into one of four grades. Pathological analysis of the placenta was performed for all patients who delivered, and in cases of hysterectomy, examination of the uterus was also performed. The placental findings and obstetric complications, including massive transfusion, intensive care unit admission and Cesarean hysterectomy, were compared with the grade of lacuna. RESULTS: Lacunae were classified as Grade 1+ in 10 cases, Grade 2+ in 11 cases, Grade 3+ in five cases and as Grade 0 (i.e. lacunae were absent) in the remaining 25 cases. When lacunae of > or = Grade 1+ were considered, the sensitivity, specificity, positive predictive value and negative predictive value of diagnosing adherent placenta were 86.9%, 78.6%, 76.9% and 88.0%, respectively. When lacunae of > or = Grade 2+ were considered, the sensitivity, specificity, positive predictive value and negative predictive value of diagnosing placenta increta or percreta were 100%, 97.2%, 93.8% and 100%, respectively. Hysterectomy was performed in 18 cases, among whom two cases showed Grade 1+ lacunae, 11 cases showed Grade 2+ lacunae, and five cases showed Grade 3+ lacunae. No hysterectomy was performed in any case in which lacunae were absent. Compared to those without lacunae, the number of massive transfusions and intensive care unit admissions and cases of disseminated intravascular coagulopathy and Cesarean hysterectomy were significantly greater in those with lacunae (P < 0.0001). CONCLUSION: Transvaginal sonographic findings of intraplacental lacunae in patients with placenta previa totalis and a history of Cesarean section are useful in the prediction of adherent placenta and may have a role in the prediction of clinical outcome.