Exploring pathophysiological insights to improve diagnostic utility of ultrasound markers for distinguishing placenta accreta spectrum from uterine-scar dehiscence.
Accurate differentiation between placenta accreta spectrum (PAS) and uterine-scar dehiscence with underlying non-adherent placenta is often challenging, even for PAS experts, both prenatally and intraoperatively. We investigated the use of standardized two-dimensional grayscale ultrasound and Doppler imaging markers in differentiating between these closely related, yet distinct, conditions.
This was a retrospective cohort study conducted in two centers with specialized PAS services. All consecutive women with at least one previous Cesarean delivery and a current pregnancy with a low-lying placenta or placenta previa, for whom detailed prenatal ultrasound, management and outcome information was available for review by the research team, were included. PAS was diagnosed clinically by the abnormal adherence of the placenta to the uterus. The PAS cases were classified using the International Federation of Gynecology and Obstetrics clinical classification. Grade 1 was considered low-grade PAS while Grades 2 and 3 were classified as high-grade PAS. The ultrasound markers were categorized according to their underlying pathophysiology, including lower uterine segment (LUS) remodeling, uteroplacental vascular remodeling and serosal hypervascularity. The combined ultrasound features were analyzed among the PAS and non-PAS subgroups using the chi-square test or Fisher's exact test, and univariable and multivariable logistic regression analysis. Additionally, receiver-operating-characteristics (ROC) curves were used to evaluate the diagnostic accuracy of the combined ultrasound features in differentiating between high-grade PAS and uterine-scar dehiscence.
Out of the 150 cases retrieved, six cases were excluded for not meeting the eligibility criteria. The included 144 cases comprised 89 cases of PAS, 23 cases of uterine-scar dehiscence and 32 cases of uncomplicated low-lying placenta or placenta previa. Among the PAS cases, there were 16 cases of low-grade PAS and 73 of high-grade PAS. Combined signs of LUS remodeling were present in most cases of uterine-scar dehiscence (20/23 (87.0%)) and high-grade PAS (67/73 (91.8%)) (P = 0.444), while these signs were absent in cases of low-grade PAS (0/16) and uncomplicated low-lying placenta or placenta previa (0/32). A subgroup analysis of cases with all LUS remodeling features present revealed that the combined signs of serosal hypervascularity (adjusted odds ratio (aOR), 41.2 (95% CI, 7.5-225.3)) and uteroplacental vascular remodeling (aOR, 116.0 (95% CI, 15.3-878.3)) were significantly associated with high-grade PAS. Diagnostic accuracy testing within this subgroup revealed an area under the ROC curve (AUC) of 0.90 (95% CI, 0.81-0.99), sensitivity of 89.6% (95% CI, 79.7-95.7%) and specificity of 90.0% (95% CI, 68.3-98.8%) for the diagnosis of high-grade PAS when all signs of uteroplacental vascular remodeling were present. If both signs of serosal hypervascularity were present, the AUC was 0.84 (95% CI, 0.74-0.95) with a sensitivity of 83.6% (95% CI, 72.5-91.5%) and specificity of 85.0% (95% CI, 62.1-96.8%) for the diagnosis of high-grade PAS.
The combined ultrasound markers of LUS remodeling are common in both high-grade PAS and uterine-scar dehiscence, while the combined features of abnormal vascularity (uteroplacental vascular remodeling and serosal hypervascularity) are specific to high-grade PAS. Understanding these pathophysiological differences would enhance the diagnostic accuracy of ultrasound in distinguishing between these two conditions. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Adu-Bredu T
，Aryananda RA
，Mathewlynn S
，Collins SL
... -
《-》
Prospective evaluation of impact of post-Cesarean section uterine scarring in perinatal diagnosis of placenta accreta spectrum disorder.
Standardized ultrasound imaging and pathology protocols have recently been developed for the perinatal diagnosis of placenta accreta spectrum (PAS) disorders. The aim of this study was to evaluate prospectively the effectiveness of these standardized protocols in the prenatal diagnosis and postnatal examination of women presenting with a low-lying placenta or placenta previa and a history of multiple Cesarean deliveries (CDs).
This was a prospective cohort study of 84 consecutive women with a history of two or more prior CDs presenting with a singleton pregnancy and low-lying placenta/placenta previa at 32-37 weeks' gestation, who were referred for perinatal care and management between 15 January 2019 and 15 December 2020. All women were investigated using the standardized description of ultrasound signs of PAS proposed by the European Working Group on abnormally invasive placenta. In all cases, the ultrasound features were compared with intraoperative and histopathological findings. Areas of abnormal placental attachment were identified during the immediate postoperative gross examination and sampled for histological examination. The data of a subgroup of 32 women diagnosed antenatally as non-PAS who had complete placental separation at birth were compared with those of 39 cases diagnosed antenatally as having PAS disorder that was confirmed by histopathology at delivery.
Of the 84 women included in the study, 42 (50.0%) were diagnosed prenatally as PAS and the remaining 42 (50.0%) as non-PAS on ultrasound examination. Intraoperatively, 66 (78.6%) women presented with a large or extended area of dehiscence and 52 (61.9%) with a dense tangled bed of vessels or multiple vessels running laterally and craniocaudally in the uterine serosa. A loss of clear zone was recorded on grayscale ultrasound imaging in all 84 cases, while there was no case with bladder-wall interruption or with a focal exophytic mass. Myometrial thinning (< 1 mm) in at least one area of the anterior uterine wall was found in 41 (97.6%) of the 42 cases diagnosed as non-PAS on ultrasound and 37 (88.1%) of the 42 diagnosed antenatally as PAS. Histological samples were available for all 48 hysterectomy specimens with abnormal placental attachment and for the three cases managed conservatively with focal myometrial resection and uterine reconstruction. Villous tissue was found directly attached to the superficial myometrium (placenta creta) in six of these cases and both creta villous tissue and deeply implanted villous tissue within the uterine wall (placenta increta) were found in the remaining 45 cases. There was no evidence of percreta placentation on histology in any of the PAS cases. Comparison of the main antenatal ultrasound signs and perioperative macroscopic findings between the two subgroups correctly diagnosed antenatally (32 non-PAS and 39 PAS) showed no significant difference with respect to the distribution of myometrial thinning and the presence of a placental bulge on ultrasound and of anterior uterine wall dehiscence intraoperatively. Compared with the non-PAS subgroup, the PAS subgroup showed significantly higher placental lacunae grade (P < 0.001) and more often hypervascularity of the uterovesical/subplacental area (P < 0.001), presence of bridging vessels (P = 0.027) and presence of lacunae feeder vessels (P < 0.001) on ultrasound examination, and increased vascularization of the anterior uterine wall intraoperatively (P < 0.001).
Remodeling of the lower uterine segment following CD scarring leads to structural abnormalities of the uterine contour on both ultrasound examination and intraoperatively, independently of the presence of accreta villous tissue on microscopic examination. These anatomical changes are often reported as diagnostic of placenta percreta, including cases with no histological evidence of PAS. Guided histological examination could improve the overall diagnosis of PAS and is essential to obtain evidence-based epidemiologic data. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Hussein AM
，Elbarmelgy RA
，Elbarmelgy RM
，Thabet MM
，Jauniaux E
... -
《-》
Bladder involvement in placenta accreta spectrum disorders: 2D US combined with the 3D crystal Vue and MRI comparative analysis.
Placental accreta spectrum (PAS) disorder with bladder involvement is found to be associated with severe maternal and neonatal morbidity.When planning surgery or other treatments, a diagnosis and assessment of the invasiveness of placenta accreta spectrum disorder with bladder involvement are crucial.The detection of the depth of villi invasion can be accomplished with both MRI and US.The advent of three-dimensional Crystal Vue provides details additional information for scanning abnorma issue.
Our goal was to compare and assess the diagnostic accuracy of 2D US combined with the 3D Crystal Vue and MRI in case of placenta accreta spectrum (PAS) involving the bladder.
111 pregnancy patients between May 2019 and November 2023 at the First Affiliated Hospital of Anhui Medical University whether or not they had placenta previa were included in the study if they were diagnosed of having placenta increta (PI) or placenta percreta (PP).Both US and MRI were used to evaluate the pregnant women.Total 53 pregnant women were ultimately included in our analysis.53 patients were split into groups with and without bladder involvement. They underwent 2D US,3D Crystal Vue, and MRI.The visual features of every subject were noted. Next, we analyzed the fundamental information, associated medical history, pregnancy outcomes, and different US and MRI signals between the two groups. To determine the potential contributing factors of PAS complicated with bladder involvement, a univariate analysis was performed. A multivariable logistic regression analysis was performed to identify US and MRI findings predictive of bladder involvement in placenta accreta spectrum.
Multiple logistic regression analysis found that the bridging vessels (OR, 31.76,95% CI, 1.64-614.31,p = 0.022) and the tramline sign "fully" obliterated on Crystal Vue feature (OR, 68.92;95%CI,6.76-702.35,p < 0.001) were independently associated with an increased likelihood of bladder involvement. These findings when combined allowed for the prediction of bladder involvement with an 88.2% sensitivity, a 94.4% specificity, and an AUC of 0.933 (95% CI,0.829-0.983, p = 0.001). The results of the MRI logistic regression analysis were as follows: the three independent risk factors for bladder involvement were: Placental bulge (OR,57.99,95%CI,3.89-835.80,p = 0.003),Bladder wall interruption (OR,11.93, 95%CI, 1.60-88.85, p = 0.016), and Bladder vessel sign (OR, 9.75,95%CI, 1.43-66.21, p = 0.020).The joint diagnosis showed a sensitivity of 94.1% and specificity of 83.3%.The area under the curve was 0.942(95%CI,0.841-0.988). Regarding projected bladder involvement, there were no statistically significant differences between MRI and 2D integrated 3D Crystal Vue imaging.
Both 2D coupled 3D Crystal Vue imaging and MRI are highly effective for predicting bladder invasion.Ultrasound is preferred over MRI because it is more convenient and more affordable.Among them, the tramline sign "fully" obliterated on 3D Crystal Vue was a new and reliable US sign for detecting bladder involvement.
Shuai X
，Gao C
，Zhang H
，Zhang T
，Li H
，Yan Y
，Yao W
，Liu Y
，Zhang C
... -
《BMC Pregnancy and Childbirth》
ResearchGate
(全网免费下载)
钛学术
(全网免费下载)
