Diagnosis Of Placental Invasion Research Articles

Validation of a scoring system for prediction of obstetric complications in placenta accreta spectrum disorders

Background Placenta accreta spectrum (PAS) refers to a spectrum of conditions characterized by the abnormal adherence of the placenta to the implantation site and has been a challenge due to the risk of postpartum hemorrhage, peripartum hysterectomy and maternal mortality. Despite of sonographic findings, no consensus on the prenatal evaluation of PAS has been established yet. We are aiming to establish a scoring system to increase the accuracy of prediction of PAS severity, especially to differentiate placenta percreta and placenta increta. Methods We conducted a retrospective study and collected 2,219 cases of placenta increta and placenta percreta obtained from 20 tertiary care centers in China. Demographic information, clinical characteristics, and sonographic findings were collected. Logistic regression analysis was used to determine the risk factors and sonographic features that were significantly associated with a clinical diagnosis of placenta percreta. The formula and subsequent scoring system were generated. This scoring system was then verified in 67 cases of placenta increta or placenta percreta in Peking University First Hospital from 2016 to 2017. Diagnosis of placental invasion was confirmed by surgical findings or histopathologic results. The scoring system was evaluated using a receiver operating characteristic (ROC) curve. Results The scoring system combined maternal risk factors and ultrasound features and was then verified in 67 cases. According to ROC curve, the area under the curve (AUC) of our scoring system for prenatal diagnosis of placenta percreta is 0.96 (95%CI, 0.91–1.00, p < .001), for severe postpartum hemorrhage (≥1500 ml) is 0.76 (95%CI, 0.62–0.91, p = .005), for hysterectomy is 0.98 (95%CI, 0.93–1.000, p = .023). Conclusions Our scoring system combining maternal risk factors and ultrasound features can improve the predictive accuracy of placenta percreta and obstetric outcomes (severe hemorrhage and hysterectomy).

Prenatal Diagnosis of Placental Invasion: A Systematic Review and Meta-analysis on Accuracy of Ultrasonography and MRI in Diagnosis of Placental Invasion

Objective: The aim of this systematic review and meta-analysis was to evaluate and compare the diagnostic accuracy of ultrasonography (US) and magnetic resonance imaging (MRI) in the diagnosis of placental invasion. Method: Two independent scientists carried out a series of searches to obtain relevant research, released from January 1, 2009, to December 31, 2018. National databases (Magiran and SID), KoreaMed, and LILACS were reviewed for literature, released in other languages. A series of MeSH keywords was employed as part of the searching strategy (e.g., pregnancy, pregnant, placental invasion, accreta). A forest plot was built with Meta-DiSc, version 1.4. Results: For placental invasion, the sensitivity and specificity of MRI were 89% (95% confidence interval [CI], 83%–93% with a 95% confidence interval) and 97% (95% CI, 93%–99%), respectively. The sensitivity and specificity of US were 73% (95% CI, 66%–79%) and 89% (95% CI, 84%–93%), respectively. In the detection of placenta accreta solely (as the first grade of placental invasion), the sensitivity and specificity of MRI were 89.3% (95% CI, 86%–92%) and 84% (95% CI, 77%–89.6%). The sensitivity and specificity of US detection were 95.4% (95% CI, 93.8%–96.6%) and 87.3% (95% CI, 81.4%–91.9%), respectively. Conclusion: Due to the increased cesarean sections, placental invasion may be increasing. The diagnosis of prenatal placental invasion is important to reduce maternal morbidity and mortality. Recent trends indicate an increased use of MRI to evaluate placental invasion as a complement to US. The most accurate imaging findings are using US for placental lacunae and MRI to detect the dark intraplacental band.

Efficiency of Endovascular Haemostasis at Delivery in Patients with Previa and Placenta Invasion

Aim. Analysis of operative delivery outcomes in pregnant women with abnormal invasive placenta depending on the endovascular treatment for intraoperative haemostasis.Materials and methods. A retrospective study of operative delivery outcomes was performed in 178 patients with placental invasion using ultrasonography (US) data obtained at the Perinatal Centre of the Regional Clinic Hospital No. 2, Ministry of Health of Krasnodar Krai, in the years 2012–2018. In 2012–2014, delivery was managed without endovascular haemostasis (n = 44), and from May 2014 to December 2018 – with prophylactic balloon catheterization of common iliac arteries (n = 134). Upon intraoperative diagnosis of placental invasion, temporary balloon occlusion (TBO, n = 115) and/or uterine artery embolization (UAE, n = 33) were performed. Efficiency of endovascular methods for intraoperative haemostasis was assessed by comparing the degree of placental invasion, amount of blood loss and transfusion, frequency of hysterectomies (HE), duration of surgery, length of stay in intensive care units (ICU) and outcomes for the foetus.Results. Adoption of endovascular methods for intraoperative haemostasis allowed the blood loss (p = 0.02), haemotransfusion (p = 0.012) and HE frequency (p &lt;0.001) to be significantly reduced. In the absence of clinical and histological manifestations of placental invasion, no difference in blood loss was detected between the groups. The amount of blood loss increased with the degree of invasion. Surgery duration in patients with TBO was signifi cantly longer (p = 0.04). No difference was detected between the groups with respect to the ICU length of stay and outcomes for the foetus.Conclusions. Establishment of endovascular haemostasis at the planned delivery of pregnant women with abnormal invasive placenta allows the blood loss and HE frequency to be reduced. Further improvement of US diagnostics of placental invasions is essential in pre-selection of patients for X-ray surgical care.

Ultrasound predictors of candidates for segmental resection in pregnants with placenta accreta

Objective: We aimed to assess the predictive values of individual sonographic findings of abnormal placentation to determine the candidates for segmental resectionStudy design: This was a retrospective review of 43 pregnancies with at least one prior cesarean delivery who received an ultrasound diagnosis of placenta previa or low-lying placenta with suspected abnormal placentation in the third trimester at our institution from 2015 through 2017. Sonographic images were reviewed by an investigator blinded to pregnancy outcome. Sonographic parameters were assessed including loss of retroplacental clear zone, irregularity and width of uterine-bladder interface, smallest myometrial thickness, presence of lacunar spaces, and bridging vessels. Diagnosis of placental invasion was based on histologic confirmation. Parameters were analyzed to predict candidates for conservative approach.Results: There were 27 cases with cesarean hysterectomy where as conservative approach was successful in 16 of the cases. Numbers of transfusions of packed red blood cells (2.6 vs. 1.7), fresh frozen plasma (2.3 vs. 0.9) and mean smallest retroplacental myometrial thickness (1.3 vs. 2.1 mm) were significantly different between the two groups (p < .05). Smallest retroplacental myometrial thickness was a significant predictor for the cases appropriate for successful conservative approach (Area Under Curve, AUC =0.911, p < .001), optimal cut off value was obtained at 1.6 mm with 94% sensitivity and 85% specificity.Conclusions: Our data showed that among some sonographic findings of abnormal placentation, smallest myometrial thickness was a significant predictor to determine candidates for conservative approach.

Magnetic Resonance Imaging and Sonography in the Diagnosis of Placental Invasion.

To compare older and newer magnetic resonance imaging (MRI) criteria for placental invasion and to compare the sensitivity, specificity, and accuracy of MRI and sonography in determining the depth of placental invasion. Forty pregnant patients at high risk for morbidly adherent placenta based on prenatal sonography underwent MRI evaluations. Two reviewers, who were blinded to the original MRI and sonographic interpretations, clinical history, and obstetric/pathologic findings, reviewed the MRI examinations. The MRI and sonographic scans were analyzed for the presence and depth of invasion. The MRI scans were tabulated for the presence of dark intraplacental T2 bands, bulging of the myometrium, increased vascularity, and indistinct myometrium, loss of the dark T2 myometrial/placental interface, and a thin myometrium. The obstetric/pathologic results served as the reference standards. Eighteen of 40 patients had a morbidly invasive placenta. The sensitivity, specificity, and accuracy of MRI and sonography were not significantly different. The accuracy rates for determining the depth of placental invasion by readers 1 and 2 were 0.65 and 0.55, respectively (P > .05). According to the Cohen κ statistic, there was a good inter-reader agreement between the MRI readers in assessing the depth of placental invasion (κ = 0.45). The features most commonly seen were dark T2 bands, bulging of the uterus, and loss of the dark T2 interface, which were all associated with the presence of placental invasion. The diagnosis of placental invasion remains challenging on sonography and MRI, which perform similarly. The presence of 2 or more criteria adds specificity to the diagnosis of placental invasion on MRI.

Ultrasound predictors of placental invasion: the Placenta Accreta Index

We sought to apply a standardized evaluation of ultrasound parameters for the prediction of placental invasion in a high-risk population. This was a retrospective review of gravidas with ≥1 prior cesarean delivery who received an ultrasound diagnosis of placenta previa or low-lying placenta in the third trimester at our institution from 1997 through 2011. Sonographic images were reviewed by an investigator blinded to pregnancy outcome and sonography reports. Parameters assessed included loss of retroplacental clear zone, irregularity and width of uterine-bladder interface, smallest myometrial thickness, presence of lacunar spaces, and bridging vessels. Diagnosis of placental invasion was based on histologic confirmation. Statistical analyses were performed using linear logistic regression and multiparametric analyses to generate a predictive equation evaluated using a receiver operating characteristic curve. Of 184 gravidas who met inclusion criteria, 54 (29%) had invasion confirmed on hysterectomy specimen. All sonographic parameters were associated with placental invasion (P < .001). Constructing a receiver operating characteristic curve, the combination of smallest sagittal myometrial thickness, lacunae, and bridging vessels, in addition to number of cesarean deliveries and placental location, yielded an area under the curve of 0.87 (95% confidence interval, 0.80-0.95). Using logistic regression, a predictive equation was generated, termed the "Placenta Accreta Index." Each parameter was weighted to create a 9-point scale in which a score of 0-9 provided a probability of invasion that ranged from 2-96%, respectively. Assignment of the Placenta Accreta Index may be helpful in predicting individual patient risk for morbidly adherent placenta.