First-trimester detection of abnormally invasive placenta in high-risk women: systematic review and meta-analysis.

The primary aim of this systematic review was to ascertain whether ultrasound signs suggestive of abnormally invasive placenta (AIP) are present in the first trimester of pregnancy. Secondary aims were to ascertain the strength of association and the predictive accuracy of such signs in detecting AIP in the first trimester. An electronic search of MEDLINE, EMBASE, CINAHL and Cochrane databases (2000-2016) was performed. Only studies reporting on first-trimester diagnosis of AIP that was subsequently confirmed in the third trimester either during operative delivery or by pathological examination were included. Meta-analysis of proportions, random-effects meta-analysis and hierarchical summary receiver-operating characteristics curve analysis were used to analyze the data. Seven studies, involving 551 pregnancies at high risk of AIP, were included. At least one ultrasound sign suggestive of AIP was detected in 91.4% (95% CI, 85.8-95.7%) of cases with confirmed AIP. The most common ultrasound feature in the first trimester of pregnancy was low implantation of the gestational sac close to a previous uterine scar, which was observed in 82.4% (95% CI, 46.6-99.8%) of cases. Anechoic spaces within the placental mass (lacunae) were observed in 46.0% (95% CI, 10.9-83.7%) and a reduced myometrial thickness in 66.8% (95% CI, 45.2-85.2%) of cases affected by AIP. Pregnancies with a low implantation of the gestational sac had a significantly higher risk of AIP (odds ratio, 19.6 (95% CI, 6.7-57.3)), with a sensitivity and specificity of 44.4% (95% CI, 21.5-69.2%) and 93.4% (95% CI, 90.5-95.7%), respectively. Ultrasound signs of AIP can be present during the first trimester of pregnancy, even before 11 weeks' gestation. Low anterior implantation of the placenta/gestational sac close to or within the scar was the most commonly seen early ultrasound sign suggestive of AIP, although its individual predictive accuracy was not high. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

D'Antonio F ，Timor-Tritsch IE ，Palacios-Jaraquemada J ，Monteagudo A ，Buca D ，Forlani F ，Minneci G ，Foti F ，Manzoli L ，Liberati M ，Acharya G ，Calì G ... -  《-》

Diagnostic accuracy of first-trimester ultrasound in detecting abnormally invasive placenta in high-risk women with placenta previa.

To ascertain the diagnostic accuracy of ultrasound in detecting abnormally invasive placenta (AIP) during the first trimester of pregnancy (11-14 weeks' gestation) in women at risk for this condition. This was a retrospective analysis of data collected prospectively from women at risk for AIP based upon the presence of at least one prior Cesarean section (CS) and/or uterine surgery and placenta previa, who had ultrasound assessment for AIP at the time of the 11-14-week scan. The ultrasound signs explored in the present study were: loss of the clear zone, placental lacunae, bladder wall interruption and uterovesical hypervascularity. The potential of ultrasound and different ultrasound signs to predict the different types of AIP was assessed by computing summary estimates of sensitivity, specificity, diagnostic odds ratio (DOR) and positive (LR+) and negative (LR-) likelihood ratios. One hundred and eighty-eight women with placenta previa and at least one previous CS or uterine surgery were included in the study. All the explored ultrasound signs were associated significantly with the occurrence of AIP. Overall, when at least one ultrasound sign was used to make the diagnosis, ultrasound had a sensitivity of 84.3% (95% CI, 74.7-91.4%), specificity of 61.9% (95% CI, 51.9-71.2%), DOR of 8.6 (95% CI, 4.1-19.3), LR+ of 2.2 (95% CI, 1.7-2.9) and LR- of 0.3 (95% CI, 0.1-0.4) in detecting AIP. Using two ultrasound signs to label a case as positive increased the diagnostic accuracy in terms of specificity, although it did not affect sensitivity. Among the different ultrasound signs, loss of the clear zone had a sensitivity of 84.3% (95% CI, 74.7-91.4%) and a specificity of 81.9% (95% CI, 73.2-88.7%) in detecting AIP, while sensitivities for placental lacunae and bladder wall interruption were 78.3% (95% CI, 67.9-86.6%) and 75.9% (95% CI, 65.3-84.6%), respectively, and specificities were 81.0% (95% CI, 72.1-88.0%) and 99.1% (95% CI, 94.8-100.0%), respectively. The optimal combination of sensitivity and specificity was achieved when at least two imaging signs of AIP were used in the diagnostic algorithm. AIP can be detected from the first trimester of pregnancy in women at risk for this condition, and ultrasound performed between 11 and 14 weeks' gestation has an overall good diagnostic accuracy for detecting all types of AIP. However, these findings are applicable only to women with placenta previa and prior uterine scar. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Cali G ，Forlani F ，Foti F ，Minneci G ，Manzoli L ，Flacco ME ，Buca D ，Liberati M ，Scambia G ，D'Antonio F ... -  《-》

First-trimester prediction of surgical outcome in abnormally invasive placenta using the cross-over sign.

Ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (cross-over sign; COS) in Cesarean scar pregnancy (CSP) has been shown to be useful in predicting the evolution of CSP towards different types of abnormally invasive placenta (AIP). The aim of this study was to ascertain whether the COS can be used to predict surgical outcome in women with AIP. A retrospective analysis was performed of early first-trimester (6-8 weeks' gestation) ultrasound images of women with AIP managed in the third trimester of pregnancy. We hypothesized that assessment of COS may identify cases of AIP at higher risk of intra- or postsurgical morbidity. Outcomes explored were estimated blood loss during surgery, need for and amount of packed red blood cells and fresh frozen plasma units required either during or after surgery, operative time, intrasurgical complications, gestational age at birth, delivery < 34 weeks of gestation, length of hospital stay and admission to intensive care unit. Differences in the explored outcomes were assessed among women with different types of COS variant (COS-1, COS-2+ or COS-2-) as observed on first-trimester ultrasound examination. Sixty-eight pregnancies were included in the study. Mean estimated blood loss was higher in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.01). Mean number of packed red blood cell units required during or after the operation was higher in women with COS-1 compared with those with COS-2+ (P = 0.001) and COS-2- (P = 0.029), while there was no difference between pregnancies with COS-2+ and those with COS-2- (P = 0.797). Mean operative time was longer in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.017). Finally, pregnancies with COS-1 were delivered earlier than those with COS-2+ (P = 0.0001) or COS-2- (P = 0.0001). First-trimester ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (COS) may identify women with AIP who are at higher risk of intra- or postsurgical morbidity. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Calì G ，Forlani F ，Minneci G ，Foti F ，Di Liberto S ，Familiari A ，Scambia G ，D'Antonio F ... -  《-》

Value of first-trimester ultrasound in prediction of third-trimester sonographic stage of placenta accreta spectrum disorder and surgical outcome.

To explore whether early first-trimester ultrasound can predict the third-trimester sonographic stage of placenta accreta spectrum (PAS) disorder and to elucidate whether combining first-trimester ultrasound findings with the sonographic stage of PAS disorder can stratify the risk of adverse surgical outcome in women at risk for PAS disorder. This was a retrospective analysis of prospectively collected data from women with placenta previa, and at least one previous Cesarean delivery (CD) or uterine surgery, for whom early first-trimester (5-7 weeks' gestation) ultrasound images could be retrieved. The relationship between the position of the gestational sac and the prior CD scar was assessed using three sonographic markers for first-trimester assessment of Cesarean scar (CS) pregnancy, reported by Calí et al. (crossover sign (COS)), Kaelin Agten et al. (implantation of the gestational sac on the scar vs in the niche of the CS) and Timor-Tritsch et al. (position of the center of the gestational sac below vs above the midline of the uterus), by two different examiners blinded to the final diagnosis and clinical outcome. The primary aim of the study was to explore the association between first-trimester ultrasound findings and the stage of PAS disorder on third-trimester ultrasound. Our secondary aim was to elucidate whether the combination of first-trimester ultrasound findings and sonographic stage of PAS disorder can predict surgical outcome. Logistic regression analysis and area under the receiver-operating-characteristics curve (AUC) were used to analyze the data. One hundred and eighty-seven women with vasa previa were included. In this cohort, 79.6% (95% CI, 67.1-88.2%) of women classified as COS-1, 94.4% (95% CI, 84.9-98.1%) of those with gestational-sac implantation in the niche of the prior CS and 100% (95% CI, 93.4-100%) of those with gestational sac located below the uterine midline, on first-trimester ultrasound, were affected by the severest form of PAS disorder (PAS3) on third-trimester ultrasound. On multivariate logistic regression analysis, COS-1 (odds ratio (OR), 7.9 (95% CI, 4.0-15.5); P < 0.001), implantation of the gestational sac in the niche (OR, 29.1 (95% CI, 8.1-104); P < 0.001) and location of the gestational sac below the midline of the uterus (OR, 38.1 (95% CI, 12.0-121); P < 0.001) were associated independently with PAS3, whereas parity (P = 0.4) and the number of prior CDs (P = 0.5) were not. When translating these figures into diagnostic models, first-trimester diagnosis of COS-1 (AUC, 0.94 (95% CI, 0.91-0.97)), pregnancy implantation in the niche (AUC, 0.92 (95% CI, 0.89-0.96)) and gestational sac below the uterine midline (AUC, 0.92 (95% CI, 0.88-0.96)) had a high predictive accuracy for PAS3. There was an adverse surgical outcome in 22/187 pregnancies and it was more common in women with, compared to those without, COS-1 (P < 0.001), gestational-sac implantation in the niche (P < 0.001) and gestational-sac position below the uterine midline (P < 0.001). On multivariate logistic regression analysis, third-trimester ultrasound diagnosis of PAS3 (OR, 4.3 (95% CI, 2.1-17.3)) and first-trimester diagnosis of COS-1 (OR, 7.9 (95% CI, 4.0-15.5); P < 0.001), pregnancy implantation in the niche (OR, 29.1 (95% CI, 8.1-79.0); P < 0.001) and position of the sac below the uterine midline (OR, 6.6 (95% CI, 3.9-16.2); P < 0.001) were associated independently with adverse surgical outcome. When combining the sonographic coordinates of the three first-trimester imaging markers, we identified an area we call high-risk-for-PAS triangle, which may enable an easy visual perception and application of the three methods to prognosticate the risk for CS pregnancy and PAS disorder, although it requires validation in large prospective studies. Early first-trimester sonographic assessment of pregnancies with previous CD can predict reliably ultrasound stage of PAS disorder. Combination of findings on first-trimester ultrasound with second- and third-trimester ultrasound examination can stratify the surgical risk in women affected by a PAS disorder. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Calí G ，Timor-Tritsch IE ，Forlani F ，Palacios-Jaraquemada J ，Monteagudo A ，Kaelin Agten A ，Flacco ME ，Khalil A ，Buca D ，Manzoli L ，Liberati M ，D'Antonio F ... -  《-》

Diagnostic accuracy of ultrasound in detecting the severity of abnormally invasive placentation: a systematic review and meta-analysis.

Our objective was to elucidate the overall diagnostic accuracy of ultrasound in detecting the severity of abnormally invasive placentation (AIP). Medline, Embase, CINAHL and The Cochrane databases were searched. The ultrasound signs explored were: loss of hypoechoic (clear) zone in the placental-uterine interface, placental lacunae, bladder wall interruption, myometrial thinning, focal exophitic mass, placental lacunar flow, subplacental vascularity, and uterovesical hypervascularity. Twenty studies (3209 pregnancies) were included. Ultrasound had an overall good diagnostic accuracy in identifying the depth of placental invasion with sensitivities of 90.6%, 93.0%, 89.5%, and 81.2% for placenta accreta, increta, accreta/increta, and percreta, respectively; the corresponding specificities were 97.1%, 98.4%, 94.7%, and 98.9%. Placental lacunae had sensitivities of 74.8%, 88.6%, and 76.3% for the detection of placenta accreta, increta, and percreta, respectively. Sensitivity and specificity of loss of the clear zone in identifying placenta accreta were 74.9% and 92.0%, whereas the corresponding figures for placenta increta and percreta were 91.6% and 76.9%, and 88.1% and 71.1%. Lacunar flow had sensitivities of 81.2%, 84.3%, and 45.2% for the detection of placenta accreta, increta, and percreta respectively; the corresponding figures for specificity were 84.0%, 79.7%, and 75.3%. Sensitivity of uterovesical hypervascularity was low for the detection of placenta accreta (12.3%) but high for placenta increta (94.4%) and percreta (86.2%); the corresponding figures for specificity were 90.8%, 88.0% and 88.2%, respectively. Ultrasound has an overall good diagnostic accuracy in recognizing the depth and the topography of placental invasion.

Pagani G ，Cali G ，Acharya G ，Trisch IT ，Palacios-Jaraquemada J ，Familiari A ，Buca D ，Manzoli L ，Flacco ME ，Fanfani F ，Liberati M ，Scambia G ，D'antonio F ... -  《-》