Prenatal identification of invasive placentation using ultrasound: systematic review and meta-analysis.
01 Nov 2013-Ultrasound in Obstetrics & Gynecology (John Wiley & Sons, Ltd)-Vol. 42, Iss: 5, pp 509-517
TL;DR: An objective of this study was to conduct a systematic review and meta‐analysis to assess the performance of ultrasound in at‐risk women for prenatal identification of invasive placentation.
Abstract: Objective
The accuracy of prospective sonographic prenatal detection of invasive placentation is unclear. The objective of this study was to conduct a systematic review and meta-analysis to assess the performance of ultrasound in at-risk women for prenatal identification of invasive placentation.
Methods
MEDLINE, EMBASE, The Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE) and The Cochrane Central Register of Controlled Trials (CENTRAL) were searched using the search terms ‘placenta accreta’, ‘placenta increta’, ‘placenta percreta’, ‘ultrasound’, ‘magnetic resonance imaging (MRI)’, ‘invasive placenta’ and ‘infiltrative placenta’. Two authors independently abstracted data from the articles. Sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR–), the diagnostic odds ratio (DOR) and their 95% CIs for each study were calculated. Forest plots and summary receiver–operating characteristics curves were produced. Between-study heterogeneity was explored both graphically and statistically. The MOOSE (meta-analysis of observational studies in epidemiology) guidelines were followed.
Results
Twenty-three studies involving 3707 pregnancies at risk for invasive placentation were included. The overall performance of ultrasound for the antenatal detection of invasive placentation was as follows: sensitivity, 90.72 (95% CI, 87.2–93.6)%; specificity, 96.94 (95% CI, 96.3–97.5)%; LR+, 11.01 (95% CI, 6.1–20.0); LR–, 0.16 (95% CI, 0.11–0.23); and DOR, 98.59 (95% CI, 48.8–199.0). Among the different ultrasound signs, color Doppler had the best predictive accuracy (sensitivity, 90.74 (95% CI, 85.2–94.7)%; specificity, 87.68 (95% CI, 84.6–90.4)%; LR+, 7.77 (95% CI, 3.3–18.4); LR–, 0.17 (95% CI, 0.10–0.29); and DOR, 69.02 (95% CI, 22.8–208.9)).
Conclusions
Ultrasound has a high accuracy for prenatal diagnosis of disorders of invasive placentation in high-risk women. The use of color Doppler improves the test performance. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.
Citations
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TL;DR: Correlation of pathological and clinical findings with prenatal imaging is essential to improve screening, diagnosis, and management of placenta accreta spectrum, and standardized protocols need to be developed.
417 citations
317 citations
Cites background from "Prenatal identification of invasive..."
...Placental lacunae give the placenta a ‘moth-eaten’ appearance on greyscale imaging and the increased vascularity of the placental bed with large feeder vessels entering the lacunae are the most common ultrasound signs associated with placenta accreta spectrum.(16,17,142,143)...
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TL;DR: In this paper, a study was conducted with patients from 3 tertiary care hospitals from July 2000 to September 2013 to test the hypothesis that a standardized multidisciplinary treatment approach in patients with morbidly adherent placenta, which includes accreta, increta and percreta is associated with less maternal morbidity than when such an approach is not used.
279 citations
TL;DR: Optimal management involves a standardized approach with a comprehensive multidisciplinary care team accustomed to management of placenta accreta spectrum, which outcomes are optimized when delivery occurs at a level III or IV maternal care facility before the onset of labor or bleeding and with avoidance of placental disruption.
273 citations
Cites background from "Prenatal identification of invasive..."
...The accuracy of MRI for the prediction of placenta accreta spectrum is reasonably good, with a systematic review reporting sensitivities of 75–100% and specificities of 65–100% (30)....
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...Magnetic resonance imaging may be useful for diagnosis of difficult cases, such as posterior placenta previa, and to assess depth of invasion in suspected percreta (30, 37, 38)....
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...8), which is comparable to ultrasonography (30)....
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...Magnetic resonance imaging features associated with placenta accreta spectrum include dark intraplacental bands on T2-weighted imaging, abnormal bulging of the placenta or uterus, disruption of the zone between the uterus and the placenta, and abnormal or disorganized placental blood vessels (30)....
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...It is unclear whether MRI improves diagnosis of placenta accreta spectrum beyond that achieved with ultrasonography (28, 30)....
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TL;DR: To assess systematically the performance of prenatal magnetic resonance imaging in diagnosing the presence, degree and topography of disorders of invasive placentation and to explore the role of the different MRI signs in predicting these disorders.
Abstract: Objective To assess systematically the performance of prenatal magnetic resonance imaging (MRI) in diagnos- ing the presence, degree and topography of disorders of invasive placentation and to explore the role of the differ- ent MRI signs in predicting these disorders. The diagnostic accuracy of ultrasound and MRI in the detection of inva- sive placentation was also compared. and 'magnetic resonance imaging'. Only prospective studies reporting a diagnosis of invasive placentation at the time of MRI and retrospective studies in which the radiologist was blinded to the final results were included in the analysis. The MRI signs explored were: uterine bulging, heterogeneous signal intensity, dark intraplacen- tal bands on T2 weighted sequences, focal interruption of the myometrium and tenting of the bladder. Summary estimates of sensitivity, specificity, positive and negative likelihood ratios (LR+, LR-) and diagnostic odds ratio (DOR) were based, depending on the number of studies, upon DerSimonian-Laird random-effect or hierarchical summary receiver-operating characteristics models. Results A total of 18 studies involving 1010 pregnancies at risk for invasive placentation were included. The over- all diagnostic accuracy of MRI in detecting the presence of invasive placentation was: sensitivity, 94.4% (95% CI, 86.0-97.9%); specificity, 84.0% (95% CI, 76.0-89.8%); LR+, 5.91 (95% CI, 3.73-9.39); LR-, 0.07 (95% CI, 0.02-0.18); DOR, 89.0 (95% CI, 22.8-348.1). MRI had
236 citations
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TL;DR: Without a way of critically appraising the information they receive, clinicians are relatively helpless in deciding what new information to learn and decide how to modify their practice.
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